Table Of Contents
VC Bundle Support and Bundle Management
Configuring IP to ATM CoS on a Single ATM VC
Defining the WRED Parameter Group
Configuring the WRED Parameter Group
Displaying the WRED Parameters
Displaying the Queueing Statistics
Configuring IP to ATM CoS on an ATM Bundle
Applying Bundle-Level Parameters
Configuring the Bundle-Level Parameters
Configuring VC Class Parameters to Apply to a Bundle
Applying Parameters to Individual VCs
Configuring a VC Bundle Member Directly
Configuring VC Class Parameters to Apply to a VC Bundle Member
Applying a VC Class to a Discrete VC Bundle Member
Configuring a VC Not to Accept Bumped Traffic
Monitoring and Maintaining VC Bundles and Their VC Members
Single ATM VC with WRED Group and IP Precedence Example
VC Bundle Configuration Using a VC Class Example
exponential-weighting-constant
IP to ATM Class of Service
This feature module describes the IP to ATM Class of Service feature. It contains the following sections:
Feature Overview
The IP to ATM Class of Service feature implements a solution for coarse-grained mapping of QoS characteristics between IP and ATM, using Cisco Enhanced ATM port adapters (PA-A3) on Cisco 7200 and 7500 series routers. (This category of coarse-grained QoS is often referred to as CoS). The resulting feature makes it possible to support differential services in network service provider environments.
IP to ATM CoS is designed to provide a true working solution to class-based services, without the investment of new ATM network infrastructures. Now networks can offer different service classes (sometimes termed differential service classes) across the entire WAN, not just the routed portion. Mission-critical applications can be given exceptional service during periods of high network usage and congestion. In addition, noncritical traffic can be restricted in its network usage, which ensures greater QoS for more important traffic and user types.
IP to ATM CoS supports configuration of the following:
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Single ATM virtual circuits (VCs)
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VC bundles
Single ATM VC Support
IP to ATM CoS support for a single ATM VC allows network managers to use existing features, such as committed access rate (CAR) or policy-based routing (PBR) to classify and mark different IP traffic by modifying the IP Precedence field in the IPv4 packet header. Subsequently, Weighted Random Early Detection (WRED) or Distributed WRED (DWRED) can be configured on a per-VC basis so that the IP traffic is subject to different drop probabilities (and therefore priorities) as IP traffic coming into a router competes for bandwidth on a particular VC.
Enhanced ATM port adapters (PA-A3) provide the ability to shape traffic on each VC according to the ATM service category and traffic parameters employed. When you use the IP to ATM CoS feature, congestion is managed entirely at the IP layer by WRED running on the routers at the edge of the ATM network.
illustrates the IP to ATM CoS support for a single ATM VC.
Figure 1 Single ATM Circuit Class
VC Bundle Support and Bundle Management
ATM VC bundle management allows you to configure multiple VCs that have different QoS characteristics between any pair of ATM-connected routers. As shown in , these VCs are grouped in a bundle and are referred to as bundle members.
Figure 2 ATM VC Bundle
ATM VC bundle management allows you to define an ATM VC bundle and add VCs to it. Each VC of a bundle has its own ATM traffic class and ATM traffic parameters. You can apply attributes and characteristics to discrete VC bundle members or you can apply them collectively at the bundle level.
Using VC bundles, you can create differentiated service by flexibly distributing IP Precedence levels over the different VC bundle members. You can map a single precedence level or a range of levels to each discrete VC in the bundle, thereby enabling individual VCs in the bundle to carry packets marked with different precedence levels. You can use WRED (or DWRED) to further differentiate service across traffic that has different IP Precedence but that uses the same VC in a bundle.
To determine which VC in the bundle to use to forward a packet to its destination, the ATM VC bundle management software matches precedence levels between packets and VCs (see ). IP traffic is sent to the next hop address for the bundle because all VCs in a bundle share the same destination, but the VC used to carry a packet depends on the value set for that packet in the IP Precedence bits of the type of service (ToS) byte of its header. The ATM VC bundle management software matches the IP Precedence of the packet to the IP Precedence value or range of values assigned to a VC, sending the packet out on the appropriate VC. Moreover, the ATM VC bundle management feature allows you to configure how traffic will be redirected when the VC the packet was matched to goes down. illustrates how the ATM VC bundle management software determines which PVC bundle member to use to carry a packet and how WRED (or DWRED) is used to differentiate traffic on the same VC.
Figure 3 ATM VC Bundle PVC Selection for Packet Transfer
The support of multiple parallel ATM VCs allows you to create stronger service differentiation at the IP layer. For instance, you might want to provide IP traffic belonging to real-time CoS (such as Voice over IP traffic) on an ATM VC with strict constraints (constant bit rate (CBR) or variable bit rate (VBR-rt), for example), while transporting traffic other than real-time traffic over a more elastic ATM available bit rate (ABR) permanent virtual circuit (PVC). Using a configuration such as this would allow you to fully utilize your network capacity. You could also elect to transport best-effort IP traffic over an unspecified bit rate (UBR) PVC—UBR is effectively the ATM version of best-effort service.
Benefits
The benefits of using the IP to ATM CoS feature include the following:
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Ensures effective differential classes over IP and traditional ATM networks. For instance, the VC bundle management feature provides for differentiated QoS by allowing for the coexistence of multiple VCs with different QoS characteristics from the same source to the same destination.
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Uses existing ATM infrastructures.
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Implements solutions for coarse-grained mapping of QoS characteristics called CoS between IP and ATM.
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Employs a high-performance design benefiting from distributed processing on the Cisco 7500 series routers and virtual interface processor (VIP).
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Uses Cisco's advanced PA-A3 ATM port adapter (PA), which supports traffic shaping and has rich ATM Service Category support. This PA is supported on the Cisco 7500+VIP and 7200 series routers.
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Provides per-VC queueing on the PA, per-VC back pressure, and per-VC WRED VIP queueing, which bring stability to a network by ensuring that system packets (such as BGP and ISIS) are never dropped.
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Provides flexible management of the VC bundle on PVC failure.
List of Terms and Acronyms
available bit rate (ABR)—An ATM service category in which the network may instruct sources to reduce their rate during times of congestion.
constant bit rate (CBR)—An ATM service category that aims to emulate a dedicated circuit of a certain fixed bandwidth.
IP Precedence—A 3-bit value in the ToS byte of the IPv4 packet header used by weighted random early detection (WRED) as a drop preference indicator.
permanent virtual circuit (PVC)—A virtual circuit that is permanently established. PVCs save bandwidth associated with circuit establishment and tear down processes in situations where certain virtual circuits must exist all the time. In ATM terminology, called a permanent virtual connection.
port adapter—Media-specific interface PCI daughter card for use on the virtual interface processor (VIP).
Random Early Detection (RED)—An algorithm that, when applied, specifies that a small percentage of packets are to be dropped when congestion is detected, that is, before the queue in question overflows completely.
type of service (ToS)—A byte in IPv4 packet header used, for example, by weighted random early detection (WRED) as a drop preference indicator.
uncommitted bit rate (UBR)—An ATM service category defined by the ATM Forum for best-effort traffic with no traffic-related service guarantees. No ATM traffic-related parameters are specified. A UBR circuit is by definition a best-effort circuit.
variable bit rate (VBR)—An ATM service category in which mean cell rate, peak cell rate, and burst tolerance are specified. A VBR circuit takes precedence over a UBR circuit in the event that there is contention for network resources.
virtual circuit (VC)—A logical circuit created to ensure reliable communication between two network devices. A VC is defined by a VPI/VCI pair, and can be either permanent (PVC) or switched (SVC). In ATM, a virtual circuit is called a virtual channel.
virtual channel identifier (VCI)—16-bit field in the header of an ATM cell. The VCI, together with the VPI, is used to identify the next destination of a cell as it passes through a series of ATM switches on its way to its destination.
Virtual Interface Processor (VIP)—Architecture for intelligent interface processors for the Cisco 7000 series routers. This architecture supports two port adapters, standard packet delivery, and distributed fast switching and feature offload.
virtual path identifier (VPI)—8-bit field in the header of an ATM cell. The VPI, together with the VCI, is used to identify the next destination of a cell as it passes through a series of ATM switches on its way to its destination.
Weighted Random Early Detection (WRED)—A variant of Random Early Detection (RED) in which the probability of a packet being dropped depends on its precedence, as well as other factors in the RED algorithm.
weighted fair queueing (WFQ)—A queueing algorithm that provides a fraction of link bandwidth (constituting the weight) to each of several queues.
Restrictions
Remember the following points when using this feature:
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IP to ATM CoS supports only PVCs.
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For PVC connections, it supports multipoint and point-to-point subinterfaces.
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For PVC encapsulations, it supports only aal5snap and aal5mux.
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IP to ATM CoS does not allow point-to-multipoint VCs in the bundle. All VCs share the same source and destination (target) addresses.
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IP to ATM CoS does not work with the ATM Interface Processor (AIP) and the ATM port adapter (PA-A1).
Supported Platforms
The IP to ATM CoS feature is supported on Cisco 2600, Cisco 3600, Cisco 7200, and Cisco 7500 series routers equipped with the following hardware:
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Cisco 7200 series:
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NPE-200 or higher (NPE-300 recommended for per-VC CBWFQ)
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One of the following Enhanced ATM port adapters (PA-A3): T3, E3, DS3, or OC-3
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Cisco 7500 series:
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VIP2-50
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One of the following Enhanced ATM port adapters (PA-A3): T3, E3, DS3, or OC-3
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Cisco 2600 and Cisco 3600 series:
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One of the following port adapters: ATM OC-3, T1 IMA, E1 IMA
Prerequisites
The IP to ATM CoS feature requires ATM PVC management and Cisco Express Forwarding (CEF) switching functionality.
Supported MIBs and RFCs
None
Functional Description
This section gives a broad overview of the IP to ATM CoS feature. It includes the following topics:
Why Use IP to ATM CoS?
Internet service classes can be identified and sorted within the router network. But as traffic traverses the wide-area ATM fabric, the relative ATM class definitions are not equivalent, and a traffic type may be treated differently in the ATM switching fabric than in the router network; mission-critical applications or data could be dropped during times of network congestion.
The IP to ATM Cos feature uses the Cisco Enhanced ATM port adapter (PA-A3) on Cisco 7500 and Cisco 7200 series routers to provide the ability to map IP CoS and ATM QoS, extending the capability previously available only for IP networks; differentiated services are preserved through the ATM network.
IP to ATM CoS Features
IP to ATM CoS includes the following features:
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Per-VC queueing infrastructure
This feature enables queues to be maintained on a per-VC basis. Packets are queued and dequeued based on the back pressure from the PA. Use of a queue per VC prevents one or more congested VCs from affecting the traffic flow on other VCs that are not congested.
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Per-VC WRED (or DWRED)
This feature applies the WRED algorithm independently to each per-VC queue. The WRED parameters are configurable on a per-VC basis so that congestion management can be configured as appropriate for each VC.
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Per-VC WRED (or DWRED) statistics
This feature maintains per-flow and per-VC statistics based on IP Precedence.
Congestion Avoidance
For each VC that is created on the Enhanced ATM port adapter (PA-A3), the PA allocates some of the buffers from its buffer pool to that VC in order to create a queue for that VC.
The use of per-VC queues ensures that a direct relationship exists between the outgoing ATM VC and the IP packets to be forwarded on that queue. This mechanism establishes a packet queue for each outgoing ATM VC. In this manner, should an ATM VC become congested, only the packet queue associated with that VC will begin to fill. If the queue overfills, then all other queues remain unaffected. Such a mechanism ensures that an individual VC cannot consume all of the resources of the router should only one of its outgoing VCs be congested or underprovisioned.
Queues for buffering more packets for a particular VC are created in the Layer 3 processor system and are mapped one-to-one to the per-VC queues on the PA. When the PA per-VC queues become congested, they signal back pressure to the Layer 3 processor; the Layer 3 processor can then continue to buffer packets for that VC in the corresponding Layer 3 queue. Furthermore, because the Layer 3 queues are accessible by the Layer 3 processor, a user can run flexible software scheduling algorithms on those queues.
When you transport data over ATM fabrics, it is essential that decisions to discard data (because of insufficient network resources or congestion) be made at the packet level. To do otherwise would be to send incomplete data packets into the ATM fabric, causing the packets to be discarded by either the ATM switched fabric (if it is equipped with early packet discard) or at the remote end where the packet will be reassembled and found to be incomplete.
To initiate effective congestion management techniques, IP to ATM CoS uses per-VC WRED (or DWRED). Per-VC WRED (or DWRED) selectively places TCP sessions in slow start to ensure higher aggregate throughput under congestion. shows low priority packets being dropped on VC1 because VC1 is congested. In this example, VC2 is not congested and all packets, regardless of priority, are transmitted.
Figure 4 Traffic Congestion with IP to ATM CoS and Per-VC WRED
Running the WRED algorithm independently on each per-VC queue provides differentiated QoS to traffic of different IP Precedence values.
Bumping and ATM VC Bundles
The ATM VC bundle is designed to behave as a single routing link to the destination router while managing the integrity of its group of circuits. The integrity of each circuit is maintained through individual monitoring. Should a circuit fail, appropriate action is taken, in the form of circuit bumping or bundle disabling.
VC integrity is maintained through ATM Operation, Administration, and Maintenance (OAM) polling mechanisms. These mechanisms will determine whether a VC is unavailable or severely congested. Should an individual circuit become unavailable, then the device consults a preset series of rules to determine what course of action to take next. These rules are defined by the Internet service provider (ISP) through configuration parameters.
conceptualizes a failed VC bundle member whose failure calls into effect the configured bumping rules.
Figure 5 VC Bundle Member Circuit Failure Enacting Bumping Rules
In the event of failure, the router responds with one of two methods. The first method dynamically assigns the traffic bound on the failed VC to an alternative VC. This is termed circuit bumping. Bumped traffic is then shared on an existing in-service VC. Traffic typically would be bumped from a higher class to a lower one, although it does not have to be. For example, should the premium, or first class, data circuit become unavailable, then all premium users would share the second class or general circuit. Preference would then be given to the premium traffic within this shared circuit.
The second method is to declare all circuits of the bundle to be down. In effect, the device is declaring the routed bundle inactive and asking the routing layer to search for an alternate.
The determination of whether to bump or whether to declare the bundle inactive is predefined by the network provider when administering the network configuration.
Configuration Tasks
You can configure IP to ATM CoS on either a single ATM VC, or on an ATM bundle. To configure IP to ATM CoS on a single ATM VC, perform the tasks in the following sections.
To configure IP to IP to ATM CoS on an ATM bundle, perform the tasks in the "Configuring IP to ATM CoS on an ATM Bundle" section later in this document.
Configuring IP to ATM CoS on a Single ATM VC
To configure IP to ATM CoS for a single ATM VC, perform the tasks in the following sections. The first two sections are required; the remaining sections are optional.
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Defining the WRED Parameter Group (Required)
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Configuring the WRED Parameter Group (Required)
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Displaying the WRED Parameters (Optional)
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Displaying the Queueing Statistics (Optional)
Defining the WRED Parameter Group
To define the Weighted Random Early Detection (WRED) parameter group, use the following command in global configuration mode:
Command Purposerandom-detect-group group-name
Defines the WRED or VIP-Distributed WRED (DWRED) parameter group.
Configuring the WRED Parameter Group
To configure the exponential weight factor for the average queue size calculation for a WRED parameter group or to configure a WRED parameter group for a particular IP precedence, use the following commands beginning in global configuration mode:
Step Command Purpose1
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random-detect-group group-name
Specifies the WRED or DWRED parameter group.
2
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exponential-weighting-constant exponent
or
precedence precedence min-threshold max-threshold mark-probability-denominatorConfigures the exponential weight factor for the average queue size calculation for the specified WRED or DWRED parameter group.
or
Configures the specified WRED or DWRED parameter group for a particular IP Precedence.
Displaying the WRED Parameters
To display the configured WRED parameters, use the following command in privileged EXEC mode:
Displaying the Queueing Statistics
To display the queueing statistics of an interface, use the following command in privileged EXEC mode:
Command Purposeshow queueing interface interface-number
[vc [[vpi/] vci]]Displays the queueing statistics of a specific VC on an interface.
Configuring IP to ATM CoS on an ATM Bundle
To configure IP to ATM CoS an ATM PVC bundle, perform the tasks in the following sections. The first four sections are required; the remaining sections are optional.
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Creating a VC Bundle (Required)
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Applying Bundle-Level Parameters (Required)
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Configuring the Bundle-Level Parameters
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Configuring VC Class Parameters to Apply to a Bundle
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Attaching a Class to a Bundle
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Committing a VC to a Bundle (Required)
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Applying Parameters to Individual VCs (Required)
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Configuring a VC Bundle Member Directly
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Configuring VC Class Parameters to Apply to a VC Bundle Member
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Applying a VC Class to a Discrete VC Bundle Member
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Configuring a VC Not to Accept Bumped Traffic (Optional)
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Monitoring and Maintaining VC Bundles and Their VC Members (Optional)
The IP to ATM CoS feature requires ATM PVC management and CEF switching functionality.
Creating a VC Bundle
To create a bundle and enter bundle configuration mode in which you can assign attributes and parameters to the bundle and all of its member VCs, use the following command in subinterface configuration mode:
Command Purposebundle bundle-name
Creates the specified bundle and enters bundle configuration mode.
Applying Bundle-Level Parameters
Bundle-level parameters can be applied either by assigning VC classes or by directly applying them to the bundle.
Parameters applied through a VC class assigned to the bundle are superseded by those applied at the bundle level. Bundle-level parameters are superseded by parameters applied to an individual VC.
Configuring the Bundle-Level Parameters
Configuring the bundle-level parameters is optional if a class is attached to the bundle to configure it.
To configure parameters that apply to the bundle and all of its members, use the following commands in bundle configuration mode:
Configuring VC Class Parameters to Apply to a Bundle
Use of a VC class allows you to configure a bundle applying multiple attributes to it at once because you apply the class itself to the bundle. Use of a class allows you to generalize a parameter across all VCs, after which (for some parameters) you can modify that parameter for individual VCs. (See the section "Applying Parameters to Individual VCs" for more information.)
To configure a VC class to contain commands that configure all VC members of a bundle when the class is applied to that bundle, use the following command in vc-class configuration mode. To enter vc-class configuration mode, use the vc-class atm command.
Command Purposeoam-bundle [manage] [frequency]
Enables end-to-end F5 OAM loopback cell generation and OAM management for all VCs in the bundle.
In addition to these commands, you can add the following commands to a VC class to be used to configure a bundle: broadcast, encapsulation, inarp, oam, and protocol commands. For information on these commands, including configuration tasks and command syntax, refer to the Cisco IOS Wide-Area Networking Configuration Guide and the Cisco IOS Wide-Area Networking Command Reference.
Attaching a Class to a Bundle
To attach a preconfigured VC class containing bundle-level configuration commands to a bundle, use the following command in bundle configuration mode:
Command Purposeclass vc-class-name
Configures a bundle with the bundle-level commands contained in the specified VC class.
Parameters set through bundle-level commands contained in the VC class are applied to the bundle and all of its VC members. Bundle-level parameters applied through commands configured directly on the bundle supersede those applied through a VC class.
Note that some bundle-level parameters applied through a VC class or directly to the bundle can be superseded by commands that you directly apply to individual VCs in bundle-vc configuration mode.
Committing a VC to a Bundle
To add a VC to an existing bundle and enter bundle-vc configuration mode, use the following command in bundle configuration mode:
Command Purposepvc-bundle pvc-name [vpi/] [vci]
Adds the specified VC to the bundle and enters bundle-vc configuration mode in order to configure the specified VC bundle member.
For information on how to first create the bundle and configure it, see the sections "Creating a VC Bundle" and "Configuring VC Class Parameters to Apply to a Bundle" earlier in this feature module.
Applying Parameters to Individual VCs
Parameters can be applied to individual VCs either by using VC classes or by directly applying them to the bundle members.
Parameters applied to an individual VC supersede bundle-level parameters. Parameters applied directly to a VC take precedence over the same parameters applied within a class to the VC at the bundle-vc configuration level.
Configuring a VC Bundle Member Directly
Configuring VC bundle members directly is optional if a VC class is attached to the bundle member.
To configure an individual VC bundle member directly, use the following command in bundle-vc configuration mode:
Parameters set directly for a VC at the bundle-vc configuration level take precedence over values for these parameters set for the VC at any other level, including application of a VC class at the bundle-vc configuration level.
Configuring VC Class Parameters to Apply to a VC Bundle Member
To configure a VC class to contain commands that configure a specific VC member of a bundle when the class is applied to it, use the following commands in VC-class configuration mode. To enter vc-class configuration mode, use the vc-class atm command in global configuration mode.
You can also add the following commands to a VC class to be used to configure a VC bundle member: ubr+ and vbr-nrt.
Use of a VC class allows you to configure a VC bundle member with multiple attributes at once because you can apply the class to the VC.
Note
When a VC is a member of a VC bundle, the following commands cannot be used in vc-class mode to configure the VC: encapsulation, protocol, inarp, and broadcast. These commands are useful only at the bundle level, not the bundle member level.
Applying a VC Class to a Discrete VC Bundle Member
To attach a preconfigured VC class containing bundle-level configuration commands to a bundle, use the following command in bundle configuration mode:
Parameters that configure a VC that are contained in a VC class assigned to that VC are superseded by parameters that are directly configured for the VC through discrete commands entered in bundle-vc configuration mode.
Configuring a VC Not to Accept Bumped Traffic
To configure an individual VC bundle member not to accept traffic that otherwise might be directed to it if the original VC carrying the traffic goes down, use the following command in bundle-vc configuration mode:
Command Purposeno bump traffic
Configures the VC not to accept any bumped traffic that would otherwise be redirected to it.
Monitoring and Maintaining VC Bundles and Their VC Members
To gather information on bundles so as to monitor them or to troubleshoot problems that pertain to their configuration or use, use one or more of the following commands in privileged EXEC mode or debug mode:
Configuration Examples
This section provides the following configuration examples:
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Single ATM VC with WRED Group and IP Precedence Example
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VC Bundle Configuration Using a VC Class Example
Single ATM VC with WRED Group and IP Precedence Example
The following example creates a PVC on an ATM interface and applies the WRED parameter group sanjose to that PVC. Next, the IP Precedence values are configured for the WRED parameter group sanjose.
interface ATM1/1/0.46 multipointip address 200.126.186.2 255.255.255.0no ip mroute-cacheshutdownpvc cisco 46encapsulation aal5nlpidrandom-detect attach sanjose!random-detect-group sanjoseprecedence 0 200 1000 10precedence 1 300 1000 10precedence 2 400 1000 10precedence 3 500 1000 10precedence 4 600 1000 10precedence 5 700 1000 10precedence 6 800 1000 10precedence 7 900 1000 10!
VC Bundle Configuration Using a VC Class Example
This example configures VC bundle management on a router that uses Intermediate System-to-Intermediate System (IS-IS) as its IP routing protocol.
Bundle-Class Class
At the outset, this configuration defines a VC class called bundle-class that includes commands that set VC parameters. When the class bundle-class is applied at the bundle level, these parameters are applied to all VCs that belong to the bundle. Note that any commands applied directly to an individual VC of a bundle in bundle-vc mode take precedence over commands applied globally at the bundle level. Taking into account hierarchy precedence rules, VCs belonging to any bundle to which the class bundle-class is applied will be characterized by these parameters: aal5snap encapsulation, broadcast on, use of Inverse ARP to resolve IP addresses, and OAM enabled.
router isis net 49.0000.0000.0000.1111.00vc-class atm bundle-class encapsulation aal5snap broadcast protocol ip inarp oam-bundle manage 3 oam 4 3 10Control-Class Class
The following sections of the configuration define VC classes that contain commands specifying parameters that can be applied to individual VCs in a bundle by assigning the class to that VC.
When the class control-class is applied to a VC, the VC carries traffic whose IP Precedence level is 7. When the VC to which this class is assigned goes down, it takes the bundle down with it because this class makes the VC a protected one. The QoS type of a VC using this class is vbr-nrt.
vc-class atm control-class precedence 7 protect vc vbr-nrt 1000 5000 32Premium-Class Class
When the class premium-class is applied to a VC, the VC carries traffic whose IP Precedence level is 6 and 5. The VC does not allow other traffic to be bumped onto it. When the VC to which this class is applied goes down, its bumped traffic will be redirected to a VC whose IP Precedence level is 7. This class makes a VC a member of the protected group of the bundle. When all members of a protected group go down, the bundle goes down. The QoS type of a VC using this class is vbr-nrt.
vc-class atm premium-class precedence 6-5 no bump traffic protect groupbump explicitly 7 vbr-nrt 20000 10000 32Priority-Class Class
When the class priority-class is applied to a VC, the VC is configured to carry traffic with IP Precedence in the 4-2 range. The VC uses the implicit bumping rule, it allows traffic to be bumped, and it belongs to the bundle's protected group. The QoS type of a VC using this class is ubr+.
vc-class atm priority-class precedence 4-2 protect group ubr+ 10000 3000Basic-Class Class
When the class basic-class is applied to a VC, the VC is configured through the precedence other command to carry traffic with IP Precedence levels not specified in the profile. The VC using this class belongs to the bundle's protected group. The QoS type of a VC using this class is ubr.
vc-class atm basic-class precedence other protect group ubr 10000The following sets of commands configure three bundles that the router subinterface uses to connect to three of its neighbors. These bundles are called new-york, san-francisco, and los-angeles. Bundle new-york has four VC members, bundle san-francisco has four VC members, and bundle los-angeles has three VC members.
New-York Bundle
The first part of this example specifies the IP address of the subinterface, the router protocol—the router uses IS-IS as an IP routing protocol, and it creates the first bundle called new-york and enters bundle configuration mode.
int a1/0.1 multipoint ip address 10.0.0.1 255.255.255.0 ip router isis bundle new-yorkFrom within bundle configuration mode, the next portion of the configuration uses two protocol commands to enable IP and Open Systems Interconnect (OSI) traffic flows in the bundle. The OSI routing packets will use the highest precedence VC in the bundle. The OSI data packets, if any, will use the lowest precedence VC in the bundle. If configured, other protocols, such as IPX or AppleTalk, will always use the lowest precedence VC in the bundle.
As the indentation levels of the preceding and following commands suggest, subordinate to bundle new-york is a command that configures its protocol and a command that applies the class bundle-class to it.
protocol ip 1.1.1.2 broadcast protocol clns 49.0000.0000.2222.00 broadcastclass bundle-classThe class called bundle-class, which is applied to the bundle new-york, includes a protocol ip inarp command. According to inheritance rules, protocol ip, configured at the bundle level, takes precedence over protocol ip inarp specified in the class bundle-class.
The next set of commands beginning with pvc-bundle ny-control 207, which are further subordinate, add four VCs (named ny-control, ny-premium, ny-priority, and ny-basic) to the bundle new-york. A particular class—that is, one of the classes predefined in this configuration example—is applied to each VC to configure it with parameters specified by commands included in the class.
As is the case for this configuration, to configure individual VCs belonging to a bundle, the router must be in bundle mode for the mother bundle. For each VC belonging to the bundle, the subordinate mode is pvc-mode for the specific VC.
The following commands configure the individual VCs for the bundle new-york.
pvc-bundle ny-control 207 class control-class pvc-bundle ny-premium 206 class premium-class pvc-bundle ny-priority 204 class priority-class pvc-bundle ny-basic 201 class basic-classSan-Francisco Bundle
The following set of commands create and configure a bundle called san-francisco. At the bundle configuration level, the configuration commands included in the class bundle-class are ascribed to the bundle san-francisco and to the individual VCs that belong to the bundle. Then, the pvc-bundle command is executed for each individual VC to add it to the bundle. After a VC is added and bundle-vc configuration mode is entered, a particular, preconfigured class is assigned to the VC. The configuration commands comprising that class are used to configure the VC. Rules of hierarchy apply at this point. Command parameters contained in the applied class are superseded by same parameters applied at the bundle configuration level, which are superseded by same parameters applied directly to a VC.
bundle san-francisco protocol clns 49.0000.0000.0000.333.00 broadcast inarp 1 class bundle-class pvc-bundle sf-control 307 class control-class pvc-bundle sf-premium 306 class premium-class pvc-bundle sf-priority 304 class priority-class pvc-bundle sf-basic 301 class basic-classLos-Angeles Bundle
The following set of commands create and configure a bundle called los-angeles. At the bundle configuration level, the configuration commands included in the class bundle-class are ascribed to the bundle los-angeles and to the individual VCs that belong to the bundle. Then, the pvc-bundle command is executed for each individual VC to add it to the bundle. After a VC is added and bundle-vc configuration mode is entered, precedence is set for the VC and the VC is either configured as a member of a protected group (protect group) or as an individually protected VC. A particular class is then assigned to each VC to further characterize it. Rules of hierarchy apply. Parameters of commands applied directly and discretely to a VC take precedence over the same parameters applied within a class to the VC at the bundle-vc configuration level, which take precedence over the same parameters applied to the entire bundle at the bundle configuration level.
bundle los-angeles protocol ip 1.1.1.4 broadcast protocol clns 49.0000.0000.4444.00 broadcastinarp 1 class bundle-classpvc-bundle la-high 407 precedence 7-5 protect vc class premium-class pvc-bundle la-mid 404 precedence 4-2 protect group class priority-class pvc-bundle la-low 401 precedence other protect group class basic-classCommand Reference
This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 12.1 command reference publications.
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bump
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exponential-weighting-constant
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pvc
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ubr
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ubr+
atm pvc
To create a permanent virtual circuit (PVC) on an ATM interface and, optionally, to generate Operation, Administration, and Maintenance (OAM) F5 loopback cells or enable Inverse ATM ARP, use the atm pvc interface configuration command. To apply a WRED parameter group to the created PVC, specify the random-detect keyword and group-name argument. The no form of this command removes the specified PVC.
Note
This command is currently supported, but it will be obsoleted in the near future. We recommend that you use the new pvc command followed by the encapsulation and random-detect attach commands instead of the atm pvc command. See "pvc" on page 56 and "random-detect" on page 61 for more information.
atm pvc vcd vpi vci aal-encap [[midlow midhigh] [peak average [burst]]] [inarp [minutes]]
[oam [seconds] [random-detect [group-name]]
no atm pvc vcd vpi vci aal-encap [[midlow midhigh] [peak average [burst]]] [inarp [minutes]]
[oam [seconds][random-detect [group-name]]Syntax Description
Defaults
If peak and average rate values are omitted, the PVC defaults to peak and average rates equal to the link rate. The peak and average rates are then equal. By default, the virtual circuit is configured to run as fast as possible.
The default of both the midlow and midhigh values is 0.
If the oam keyword is omitted, OAM cells are not generated. If the oam keyword is present but the seconds value is omitted, the default value of oam seconds is 10 seconds.
If the inarp keyword is omitted, inverse ARPs are not generated. If the inarp keyword is present, but the timeout value is not given, then inverse ARPs are generated every 15 minutes.
When the random-detect keyword is used, if the group-name argument is omitted or no name match is found in the current configuration for the specified group-name, a set of default WRED parameters are applied to the PVC.
If the random-detect keyword is omitted, WRED is turned off for the PVC.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0. The midlow and midhigh arguments first appeared in Cisco IOS Release 10.3.
This command is used for single VCs, not VC bundles. However, the atm pvc command will be obsoleted in the near future, so we discourage use of it. See the note preceding the command syntax for information on the commands that replace it.
The oam seconds and inarp minutes arguments first appeared in Cisco IOS Release 11.0. The random-detect keyword first appeared in Cisco IOS Release 11.1(22)CC.
Because the ATM port adapters do not support traffic shaping, the peak, average, and burst rate options are not available. For more information on the ATM port adapter, refer to the PA-A1 ATM Port Adapter Installation and Configuration publication.
The order of command options is important. The inarp keyword can be specified either separately or before the oam keyword has been enabled. The peak, average, and burst arguments, if specified, cannot be specified after either the inarp or the oam keywords.
The Cisco IOS software dynamically creates rate queues as necessary to satisfy the requests of atm pvc commands. The software dynamically creates a rate queue when an atm pvc command specifies a peak or average rate that does not match any user-configured rate queue.
The atm pvc command creates a PVC and attaches it to the VPI and VCI specified. Both vpi and vci cannot be specified as 0; if one is 0, the other cannot be 0. The aal-encap argument determines the AAL mode and the encapsulation method used. The peak and average arguments determine the rate queue used.
Use one of the aal5mux encapsulation options to dedicate the specified virtual circuit to a single protocol; use the aal5snap encapsulation option to multiplex two or more protocols over the same virtual circuit. Whether you select aal5mux or aal5snap encapsulation might depend on practical considerations, such as the type of network and the pricing offered by the network. If the network's pricing depends on the number of virtual circuits set up, aal5snap might be the appropriate choice. If pricing depends on the number of bytes transmitted, aal5mux might be the appropriate choice because it has slightly less overhead.
If you choose to specify peak or average values, you must specify both. If you set the peak and average values for aal34smds encapsulation, you must also specify the midlow and midhigh values. aal34smds encapsulation is not available for the ATM port adapter.
In the 7000 router series family (AIP), the values for peak and average indicate the bandwidth as seen on the wire.
In the 4500 router series family, (ATMizer), the values for peak and average indicate the bandwidth of the AAL5 payload (exclusive of padding).
Message identifier (MID) numbers, which are available only with aal34smds encapsulation, are used by receiving devices to reassemble cells from multiple packets. You can assign different midlow to midhigh ranges to different PVCs to ensure that the message identifiers are unique at the receiving end and, therefore, that messages can be reassembled correctly.
When configuring an SVC, use the atm pvc command to configure the PVC that handles the SVC call setup and termination. In this case, specify the qsaal encapsulation for the aal-encap keyword. See the third example that follows.
The router generates and echoes OAM F5 loopback cells, which verify connectivity. Once OAM cell generation is enabled, a cell is transmitted periodically. The remote end must respond by echoing back the cells.
The router does not generate alarm indication signal (AIS) cells, which are used for alarm surveillance functions. However, if it receives an AIS cell, it responds by sending an OAM far-end remote failure (FERF) cell.
Examples
The following example creates a PVC with VPI 0 and VCI 6. The PVC uses AAL AAL5-MUX with IP protocol.
atm pvc 1 0 6 aal5mux ipThe following example creates a PVC with VPI 0 and VCI 6. The PVC uses AAL AAL3/4-SMDS protocol.
atm pvc 1 0 6 aal34smds 0 15 150000 70000 10The following example creates a PVC to be used for ATM signaling for an SVC. It specifies VPI 0 and VCI 5.
atm pvc 1 0 5 qsaalAssuming that no static rate queue has been defined, the following example creates the PVC and also creates a dynamic rate queue with the peak rate set to the maximum allowed by the physical layer interface module (PLIM) and the average set to equal the peak rate:
atm pvc 1 1 1 aal5snapAssuming that no static rate queue has been defined, the following example creates the PVC and also creates a dynamic rate queue with the peak rate set to 100 Mbps (100,000 kbps), the average rate set to 50 Mbps (50,000 kbps), and a burst size of 64 cells (2 * 32 cells):
atm pvc 1 1 1 aal5snap 100000 50000 2The following example creates a PVC to be used for IP to ATM Class of Service (IP to ATM CoS). It specifies VPI 0 and VCI 46. The PVC uses aal5nlpid encapsulation and the WRED parameter group "sanjose" is applied to the PVC.
atm pvc 1 0 46 aal5nlpid random-detect sanjoseRelated Commands
atm aal aal3/4
atm maxvc
atm multicast
atm rate-queue
atm smds-address
mtu
random-detect-group
show queueing interface
show queueing redbroadcast
To configure broadcast packet duplication and transmission for an ATM VC class, PVC, SVC, or VC bundle, use the broadcast command in the appropriate command mode. To disable broadcast forwarding for your ATM VC class, PVC, SVC, or VC bundle. Use the no form of this command to disable broadcast packet duplication. Use the default form of this command to restore the default behavior according to the description in the following "Usage Guidelines" section.
broadcast
no broadcast
default broadcastSyntax Description
This command has no arguments or keywords.
Default
Disabled. For classical IP SVCs, broadcast is enabled.
Command Mode
Interface-ATM-VC configuration (for ATM PVCs and SVCs).
VC-class configuration (for a VC-class).
Bundle configuration (for a VC bundle).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T. For Cisco IOS Release 12.0(3)T, this command has been enhanced to enable configuration of broadcast packet duplication and transmission for an ATM VC bundle.
If broadcasting and multipoint signalling are enabled on an SVC, a multipoint SVC will be created to handle the SVC.
Note
If you use the broadcast command to configure broadcasting for an ATM PVC or SVC, VC-class, or VC bundle, this configuration takes precedence over any previous configuration using the broadcast command.
If the broadcast command is not explicitly configured on an ATM PVC, SVC, or VC bundle, the VC inherits the following default configuration (listed in order of next highest precedence):
•
Configuration of the broadcast command in a VC class assigned to the PVC, SVC, or VC bundle itself.
•
Configuration of the broadcast command in a VC class assigned to the PVC's, SVC's, or VC bundle's ATM subinterface.
•
Configuration of the broadcast command in a VC class assigned to the PVC's, SVC's, or VC bundle's ATM main interface.
Note
When a VC is a member of a VC bundle, configuration using the broadcast command in VC-class configuration mode no longer applies to the VC. Bundle configuration takes precedence.
To use the broadcast command in bundle configuration mode, enter the bundle command to enact bundle configuration mode for the bundle for which you want to enable broadcast forwarding.
Examples
The following example enables the transmission of broadcast packets on an ATM PVC named router5:
pvc router5 1/32 broadcastThe following example enables the transmission of broadcast packets on an ATM PVC bundle named chicago:
bundle chicago broadcastRelated Commands
class
encapsulation
inarp
oam-bundle
oam-retry
protocol
ubr
ubr+
vbr-nrtbump
To configure the bumping rules for a virtual circuit (VC) class that can be assigned to a VC bundle, use the bump VC-class configuration command. Use the no bump explicit precedence-level form of this command to remove the explicit bumping rules for the VCs assigned this class and default them to implicit bumping. The no bump traffic form of this command specifies that the VC bundle members do not accept any bumped traffic.
To configure the bumping rules for a specific VC member of a bundle, use the bump bundle-vc configuration command. Use the no bump explicit precedence-level form of this command to remove the explicit bumping rules for the VC and default it to implicit bumping. The no form of this command specifies that the VC does not accept any bumped traffic.
bump {implicit | explicit precedence-level | traffic}
no bump {explicit precedence-level | traffic}Syntax Description
Defaults
Implicit bumping.
Bump traffic (VCs accept bumped traffic).
Command Modes
VC-class configuration (for a VC class).
Bundle-vc configuration (for a VC bundle member).
Usage Guidelines
This command first appeared in Release 12.0(3)T.
Use the bump command in bundle-vc configuration mode to configure bumping rules for a discrete VC bundle member or in VC class mode to configure a VC class that can be assigned to a bundle member.
The effects of different bumping configuration approaches are as follows:
•
Implicit bumping: If you configure implicit bumping, bumped traffic is sent to the VC configured to handle the next lower precedence level. When the original VC that bumped the traffic comes back up, traffic it is configured to carry is restored to it. When no other positive forms of the bump command are configure, bump implicit takes effect.
•
Explicit bumping: If you configure a VC with the bump explicit command, you can specify explicitly the precedence level to which traffic on a VC will be bumped when that VC goes down and the traffic will be directed to a VC mapped with that precedence level. If the VC that picks up and carries the traffic goes down, the traffic is subject to the bumping rules for that VC. You can specify only one precedence level for bumping.
•
Bumped traffic: The VC accepts bumped traffic. You can configure bumped traffic explicitly using either bump traffic nor no bump traffic, or let the default take effect by specifying neither.
•
No bumped traffic: To configure a discrete VC to reject bumped traffic when the traffic is directed to the VC, use with the no bump traffic command.
Note
When no alternative VC can be found to handle bumped traffic, the bundle is declared down. To avoid this occurrence, configure explicitly the bundle member VC that has the lowest precedence level.
To use this command in vc-class configuration mode, you must enter the vc-class atm global configuration command before you enter this command.
To use this command to configure an individual bundle member in bundle-vc configuration mode, first enter the bundle command to enact bundle configuration mode for the bundle to which you want to add or modify the VC member to be configured. Then, use the pvc-bundle command to specify the VC to be created or modified and enter bundle-vc configuration mode.
This command has no effect if the VC class that contains the command is attached to a standalone VC, that is, if the VC is not a bundle member. In this case, the attributes are ignored by the VC.
VCs in a VC bundle are subject to the following configuration inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode (with effect of assigned VC-class configuration)
•
Subinterface configuration in subinterface mode
Example
The following example configures the class premium-class to define parameters applicable to a VC in a bundle. Unless overridden with a bundle-vc bump configuration, the VC that uses this class will not allow other traffic to be bumped onto it.
vc-class atm premium-classno bump traffic bump explicitly 7Related Commands
class-vc
precedence
protect
ubr
ubr+
vbr-nrt
bundle
To create a bundle or modify an existing bundle to enter bundle configuration mode, use the bundle subinterface configuration command. The no form of this command removes the specified bundle.
bundle bundle-name
no bundle bundle-nameSyntax Description
Default
None
Command Mode
Subinterface configuration
Usage Guidelines
This command first appeared in Release 12.0(3)T.
From within bundle configuration mode you can configure the characteristics and attributes of the bundle and its members, such as the encapsulation type for all virtual circuits (VCs) in the bundle, the bundle management parameters, the service type, and so on. Attributes and parameters you configure in bundle configuration mode are applied to all VC members of the bundle.
VCs in a VC bundle are subject to the following configuration inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode
•
Subinterface configuration in subinterface mode
To display status on bundles, use the show atm bundle and show atm bundle statistics commands.
Example
The following example configures a bundle called new-york. The example specifies the IP address of the subinterface, the router protocol—the router uses IS-IS as an IP routing protocol, then configures the bundle.
int a1/0.1 multipoint
ip address 10.0.0.1 255.255.255.0
ip router isis
bundle new-yorkRelated Commands
class-bundle
oam-bundle
pvc-bundleclass
To assign a VC-class to an ATM main interface, subinterface, permanent virtual circuit (PVC), switched virtual circuit (SVC), a virtual circuit (VC) bundle, or VC bundle member, use the class command in the appropriate command mode. The no form of this command removes a VC class.
class vc-class-name
no class vc-class-nameSyntax Description
vc-class-name
Name of the VC class you are assigning to your ATM main
interface, subinterface, PVC, SVC, VC bundle, or VC bundle
member.
Default
No VC class is assigned.
Command Modes
Interface configuration (for ATM main and subinterfaces).
Interface-ATM-VC configuration (for ATM PVCs and SVCs).
Bundle configuration (for ATM VC bundles).
Bundle-vc configuration (for ATM VC bundle members).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T. For Cisco IOS Release 12.0(3)T, this command has been modified to support application of a class to an ATM VC bundle and an ATM VC bundle member.
Use this command to assign a previously defined set of parameters to an ATM main interface, subinterface, PVC, SVC, VC bundle, or VC bundle member. This set of parameters is defined in a VC class.
To use this command in bundle-vc configuration mode, first enter the bundle command to enact bundle configuration mode for the bundle to which you want to add and then configure a VC or modify an existing VC member. Then, use the pvc-bundle command to specify the VC to be created or modified and enter bundle-vc configuration mode.
To use this command in bundle configuration mode, you must enter the bundle command to create the bundle and then enter bundle configuration mode.
Examples
The following example assigns a VC class named atm-ubr to a PVC named router5. This VC class may contain uncommitted bit rate (UBR) settings that were configured using the ubr command.
pvc router5 1/32class atm-ubrThe following example assigns a VC class named atm-svc-parameters to an SVC named lion. This VC class may contain ATM SVC default parameters.
svc lion 47.0091.81.000000.0040.0B0A.2501.ABC1.3333.3333.05 class atm-svc-parametersThe following example assigns a VC class named control-class to VC 207, which is a bundle member:
pvc-bundle star-control 207 class control-classRelated Commands
broadcast
bump
bundle
encapsulation
inarp
oam-bundle
oam-retry
precedence
protect
protocol
pvc-bundle
ubr
ubr+
vbr-nrt
vc-class atmdebug atm bundle errors
To enable the display of information on bundle errors, use the debug atm bundle errors debug command.
debug atm bundle errors
Syntax Description
This command has no arguments or keywords.
Default
None
Command Mode
Debug
Usage Guidelines
This command first appeared in Cisco IOS Release 12(0) 3T.
Use this command to enable the display of error information for a bundle, such as reports of inconsistent mapping in the bundle.
Related Commands
bump
bundle
debug atm bundle eventsdebug atm bundle events
To enable display of bundle events when use occurs, use the debug atm bundle events command in debug mode.
debug atm bundle events
Syntax Description
This command has no arguments or keywords.
Default
None
Command Mode
Debug
Usage Guidelines
This command first appeared in Cisco IOS Release 12(0)3T.
Use this command to enable the display of bundle events, such as occurrences of VC bumping, when bundles were brought up, when they were taken down, and so forth.
Related Command
debug atm bundle errors
encapsulation
To configure the ATM adaptation layer (AAL) and encapsulation type for an ATM (permanent virtual circuit) PVC, (switched virtual circuit) SVC, (virtual class) VC class, or VC bundle, use the encapsulation command in the appropriate command mode. The no form of this command removes an encapsulation from a PVC, SVC, VC class, or VC bundle.
encapsulation aal-encap [virtual-template number]
no encapsulation aal-encap [virtual-template number]
Note
To configure ILMI, QSAAL, or SMDS encapsulations for an ATM PVC, use the pvc command.
Syntax Description
Default
The global default encapsulation is aal5snap. See the "Usage Guidelines" section for other default characteristics.
Command Modes
Interface-ATM-VC configuration (for an ATM PVC or SVC).
VC-class configuration (for a VC class).
Bundle configuration (for a VC bundle).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T. For Cisco IOS Release 12(0)3T, this command has been enhanced to provide encapsulation configuration for ATM VC bundles.
A VC bundle can have only one encapsulation configured for it: either aal5snap or aal5mux.
Use one of the aal5mux encapsulation options to dedicate the specified PVC to a single protocol; use the aal5snap encapsulation option to multiplex two or more protocols over the same PVC. Whether you select aal5mux or aal5snap encapsulation might depend on practical considerations, such as the type of network and the pricing offered by the network. If the network's pricing depends on the number of PVCs set up, aal5snap might be the appropriate choice. If pricing depends on the number of bytes transmitted, aal5mux might be the appropriate choice because it has slightly less overhead.
To use this command to configure a VC bundle, first enter the bundle subinterface configuration command to create a new bundle or modify an existing one and to enter bundle configuration mode.
Note
When a VC is a member of a VC bundle, configuration using the encapsulation command in VC class mode no longer applies to the VC. Bundle configuration takes precedence.
When configuring Cisco PPP over ATM, specify the aal5ciscoppp encapsulation for the aal-encap argument and specify the virtual template number.
It is possible to implicitly create a virtual template when configuring Cisco PPP over ATM. In other words, if the parameters of the virtual template are not explicitly defined before you configure the ATM PVC, the PPP interface will be brought up using default values from the virtual template identified. However, some parameters (such as an IP address) take effect only if they are specified before the PPP interface comes up. Therefore, we recommend that you explicitly create and configure the virtual template before configuring the ATM PVC to ensure such parameters take effect.
If you specify virtual template parameters after the ATM PVC is configured, you should enter a shutdown command followed by a no shutdown command on the ATM subinterface to restart the interface, causing the newly configured parameters (such as an IP address) to take effect.
If the encapsulation command is not explicitly configured on an ATM PVC, SVC, or VC bundle, the VC inherits the following default configuration (listed in order of next highest precedence):
•
Configuration of the encapsulation command in a VC class assigned to the PVC, PVC bundle, or SVC itself.
•
Configuration of the encapsulation command in a VC class assigned to the PVC's, SVC's, or VC bundle's ATM subinterface.
•
Configuration of the encapsulation command in a VC class assigned to the PVC's, SVC's, or VC bundle's ATM main interface.
•
Global default: aal-encap = aal5snap.
Examples
The following example configures an ATM PVC with VPI 0 and VCI 33 for a MUX-type encapsulation using IP:
pvc 0/33 encapsulation aal5mux ipThe following example configures a bundle called chicago for aal5snap encapsulation.
bundle chicago encapsulation aal5snapRelated Commands
broadcast
class
inarp
oam-bundle
oam retry
protocolexponential-weighting-constant
To configure the exponential weight factor for the average queue size calculation for a WRED parameter group, use the exponential-weighting-constant command in random-detect-group mode. The no form of this command returns the group's value to the default.
exponential-weighting-constant exponent
no exponential-weighting-constantSyntax Description
Default
The weight factor is 9.
Command Mode
Random-detect-group configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.1(22)CC. If used, this command is issued after the random-detect-group command.
Use this command to change the exponent used in the average queue size calculation for a WRED parameter group. The average queue size is based on the previous average and the current size of the queue. The formula is:
average = (old_average * (1-1/2^n)) + (current_queue_size * 1/2^n)where n is the exponential weight factor specified in this command. Thus, the higher the factor, the more dependent the average is on the previous average.
Note
The default WRED parameter values are based on the best available data. We recommend that you do not change the parameters from their default values unless you have determined that your applications would benefit from the changed values.
For high values of n, the previous average becomes more important. A large factor smooths out the peaks and lows in queue length. The average queue size is unlikely to change very quickly, avoiding drastic swings in size. The WRED process will be slow to start dropping packets, but it may continue dropping packets for a time after the actual queue size has fallen below the minimum threshold. The slow-moving average will accommodate temporary bursts in traffic.
If the value of n gets too high, WRED will not react to congestion. Packets will be transmitted or dropped as if WRED were not in effect.
For low values of n, the average queue size closely tracks the current queue size. The resulting average may fluctuate with changes in the traffic levels. In this case, the WRED process responds quickly to long queues. Once the queue falls below the minimum threshold, the process will stop dropping packets.
If the value of n gets too low, WRED will overreact to temporary traffic bursts and drop traffic unnecessarily.
Example
The following example configures the WRED group sanjose with a weight factor of 10:
random-detect-group sanjoseexponential-weighting-constant 10Related Commands
protect
random-detect exponential-weighting constant
random-detect-group
show queueing interface
show queueing redinarp
To configure the Inverse ARP time period for an ATM permanent virtual circuit (PVC), (virtual circuit) VC class, or VC bundle, use the inarp command in the appropriate command mode. The no form of this command stores the default Inverse ARP time period behavior.
inarp minutes
no inarp minutesSyntax Description
Default
When Inverse ARP is enabled, minutes = 15 minutes.
Command Modes
Interface-ATM-VC configuration (for an ATM PVC).
VC-class configuration (for a VC class).
Bundle configuration (for a VC bundle).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T. For Cisco IOS Release 12.0(3)T, this command has been enhanced to provide support to configure the Inverse ARP time period for an ATM VC bundle.
This command is only supported for aal5snap encapsulation when Inverse ARP is enabled. Refer to the encapsulation command for configuring aal5snap encapsulation and the protocol command for enabling Inverse ARP.
If the inarp command is not explicitly configured on an ATM PVC, the PVC inherits the following default configuration (listed in order of next highest precedence):
•
Configuration of the inarp command in a VC class assigned to the PVC itself.
•
Configuration of the inarp command in a VC class assigned to the PVC's ATM subinterface.
•
Configuration of the inarp command in a VC class assigned to the PVC's ATM main interface.
•
Global default: minutes = 15 minutes; this default assumes that Inverse ARP is enabled.
Note
As the inheritance rules imply, when a VC is a member of a VC bundle, configuration using the inarp command in VC class configuration mode no longer applies to that VC. Bundle configuration takes precedence.
For ATM VC bundle management, the Inverse ARP parameter can only be enabled at the bundle level and applied to all VC members of the bundle—that is, it cannot be enabled in bundle-vc configuration mode for individual VC bundle members. To use this command in bundle configuration mode, first enter the bundle command to create the bundle and enter bundle configuration mode.
Example
The following example sets the Inverse ARP time period to 10 minutes:
inarp 10Related Commands
bundle
broadcast
class
encapsulation
oam-bundle
oam retry
protocoloam-bundle
To enable end-to-end F5 operation, administration, and maintenance (OAM) loopback cell generation and OAM management for a virtual circuit (VC) class that can be applied to a VC bundle, use the oam-bundle vc-class configuration command. The no form of this command removes OAM management from the class configuration.
To enable end-to-end F5 OAM loopback cell generation and OAM management for all VC members of a bundle, use the oam-bundle bundle configuration command. Use the no form of this command to remove OAM management from the bundle.
oam-bundle [manage] [frequency]
no oam-bundle [manage] [frequency]Syntax Description
Defaults
End-to-end F5 OAM loopback cell generation and OAM management are disabled, but if OAM cells are received, they are looped back. The default value for the frequency is 10 seconds.
Command Modes
VC-class configuration (for a VC class).
Bundle configuration (for an ATM VC bundle).
Interface configuration (for ATM main and subinterfaces).
Usage Guidelines
This command first appeared in Release 12.0(3)T.
This command defines whether a VC bundle is OAM-managed. If this command is configured for a bundle, every VC member of the bundle is OAM-managed. If OAM management is enabled, further control of OAM management is configured using the oam retry command.
This command has no effect if the VC class that contains the command is attached to a standalone VC, that is, if the VC is not a bundle member. In this case, the attributes are ignored by the VC.
To use this command in bundle configuration mode, enter the bundle subinterface configuration command to create the bundle or to specify an existing bundle before you enter this command.
To use this command in VC-class configuration mode, first enter the vc-class atm global configuration command.
VCs in a VC bundle are subject to the following configuration inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode (with effect of assigned VC-class configuration)
•
Subinterface configuration in subinterface mode
Example
The following example enables OAM management for a bundle called chicago:
bundle chicago oam-bundle manageRelated Commands
broadcast
class-bundle
encapsulation
inarp
oam retry
protocol (ATM)
oam retry
To configure parameters related to OAM management for an ATM permanent virtual circuit (PVC), switched virtual circuit (SVC), virtual circuit (VC) class, or VC bundle, use the oam retry command in the appropriate command mode. The no form of this command removes OAM management parameters.
oam retry up-count down-count retry-frequency
no oam retry up-count down-count retry-frequencySyntax Description
Defaults
up-count = 3, down-count = 5, retry-frequency = 1 second. This set of defaults assumes that OAM management is enabled using the oam-pvc or oam-svc command. The up-count argument does not apply to SVCs.
Command Modes
Interface-ATM-VC configuration (for an ATM PVC or SVC).
VC-class configuration (for a VC class).
Bundle configuration mode (for a VC bundle).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T. For Cisco IOS Release 12.0(3)T, this command allows you to configure parameters related to OAM management for ATM VC bundles.
If the oam retry command is not explicitly configured on an ATM PVC, SVC, or VC bundle, the VC inherits the following default configuration (listed in order of next highest precedence):
•
Configuration of the oam retry command in a VC class assigned to the PVC or SVC itself.
•
Configuration of the oam retry command in a VC class assigned to the PVC's or SVC's ATM subinterface.
•
Configuration of the oam retry command in a VC class assigned to the PVC's or SVC's ATM main interface.
•
Global default: up-count = 3, down-count = 5, retry-frequency = 1 second. This set of defaults assumes that OAM management is enabled using the oam-pvc or oam-svc command. The up-count and retry-frequency arguments do not apply to SVCs.
To use this command in bundle configuration mode, enter the bundle command to create the bundle or to specify an existing bundle before you enter this command.
If you use the oam retry command to configure a VC bundle, you configure all VC members of that bundle. VCs in a VC bundle are further subject to the following inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode (with effect of assigned VC-class configuration)
•
Subinterface configuration in subinterface mode
Example
The following example configures the OAM management parameters with up-count 3, down-count 3, and the retry-frequency at 10 seconds:
oam retry 3 3 10Related Commands
broadcast
class
encapsulation
inarp
oam-bundle
oam-pvc
oam-svc
protocol
ubr
ubr+
vbr-nrtprecedence (VC bundle)
To configure precedence levels for a virtual circuit (VC) class that can be assigned to a VC bundle and thus applied to all VC members of that bundle, use the precedence VC-class configuration command. The no form of this command removes the precedence levels from the VC class.
To configure the precedence levels for a VC member of a bundle, use the precedence bundle-vc configuration command. The no form of this command removes the precedence levels from the VC.
precedence [other | range]
no precedenceSyntax Description
Default
Defaults to other, that is, any precedence levels in the range of 0 to 7 (0-7) that are not explicitly configured.
Command Mode
VC-class configuration (for a VC class).
Bundle-vc configuration (for ATM VC bundle members).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.1(22)CC. For Cisco IOS Release 12.0(3)T, this command has been extended to configure precedence levels for a VC member of a bundle.
Assignment of precedence levels to VC bundle members allows you to create differentiated service because you can distribute the IP Precedence levels over the different VC bundle members. You can map a single precedence level or a range of levels to each discrete VC in the bundle, thereby enabling VCs in the bundle to carry packets marked with different precedence levels. Alternatively, you can configure a VC with the precedence other command to indicate that it can carry traffic marked with precedence levels not specifically configured for it. Only one VC in the bundle can be configured with precedence other to carry all precedence levels not specified. This VC is considered the default one.
To use this command in VC-class configuration mode, enter the vc-class atm global configuration command before you enter this command. This command has no effect if the VC class that contains the command is attached to a standalone VC, that is, if the VC is not a bundle member.
To use this command to configure an individual bundle member in bundle-vc configuration mode, first enter the bundle command to enact bundle configuration mode for the bundle to which you want to add or modify the VC member to be configured. Then, use the pvc-bundle command to specify the VC to be created or modified and enter bundle-vc mode.
VCs in a VC bundle are subject to the following configuration inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode (with effect of assigned VC-class configuration)
•
Subinterface configuration in subinterface mode
Examples
The following example configures a class called control-class that includes a precedence command, that, when applied to a bundle, configures all VC members of that bundle to carry IP Precedence level 7 traffic. Note, however, that VC members of that bundle can be individually configured with the precedence command at the bundle-vc level, which would supervene.
vc-class atm control-class precedence 7The following example configures PVC 401 (with the name of control-class) to carry traffic with IP Precedence levels in the range of 4-2, overriding the precedence level mapping set for the VC through VC-class configuration.
pvc-bundle control-class 401 precedence 4-2Related Commands
bump
class-vc
protect
ubr
ubr+
vbr-nrtprecedence (WRED group)
To configure a Weighted Random Early Detection (WRED) or VIP-Distributed WRED (DWRED) group for a particular IP Precedence, use the precedence command in random-detect-group mode. The no form of this command returns the group's values to the default for the IP Precedence.
precedence precedence min-threshold max-threshold mark-probability-denominator
no precedence precedence min-threshold max-threshold mark-probability-denominatorSyntax Description
Default
For all IP Precedences, the mark-probability-denominator is 10, and the max-threshold is based on the output buffering capacity and the transmission speed for the interface.
The default min-threshold depends on the IP Precedence. The min-threshold for IP Precedence 0 corresponds to half of the max-threshold. The values for the remaining IP precedences fall between half the max-threshold and the max-threshold at evenly spaced intervals. Table 1 lists the default minimum value for each IP Precedence.
Table 1 Default WRED Minimum Threshold Values
IP Precedence Minimum Threshold Value (Fraction of Maximum Threshold Value)0
8/16
1
9/16
2
10/16
3
11/16
4
12/16
5
13/16
6
14/16
7
15/16
Command Mode
Random-detect-group
Usage Guidelines
WRED is a congestion avoidance mechanism that slows traffic by randomly dropping packets when congestion exists. DWRED is similar to WRED but uses the Versatile Interface Processor (VIP) instead of the Route Switch Processor (RSP).
This command first appeared in Cisco IOS Release 11.1(22)CC. If used, this command is issued after the random-detect-group command.
When you configure the random-detect group command on an interface, packets are given preferential treatment based on the IP Precedence of the packet. Use the precedence command to adjust the treatment for different IP Precedences.
If you want WRED (DWRED) to ignore the IP Precedence when determining which packets to drop, enter this command with the same parameters for each IP Precedence. Remember to use reasonable values for the minimum and maximum thresholds.
Note
The default WRED (DWRED) parameter values are based on the best available data. We recommend that you do not change the parameters from their default values unless you have determined that your applications would benefit from the changed values.
Example
The following example specifies parameters for WRED parameter group sanjose for the different IP precedences:
random-detect-group sanjoseprecedence 0 32 256 100precedence 1 64 256 100precedence 2 96 256 100precedence 3 128 256 100precedence 4 160 256 100precedence 5 192 256 100precedence 6 224 256 100precedence 7 256 256 100Related Commands
exponential-weighting-constant
random-detect (per-VC)
random-detect-group
random-detect precedence
show queueing
show queueing interfaceprotect
To configure a virtual circuit (VC) class with protected group or protected VC status for application to a VC bundle member, use the protect command in VC-class configuration mode. The no form of this command removes the protected status from the VC class.
To configure a specific VC as part of the bundle's protected group or configure it as an individually protected VC bundle member, use the protect command in bundle-vc configuration mode. The no form of this command removes the protected status from the VC.
protect {group | vc}
no protect {group | vc}Syntax Description
group
Configures the VC bundle member to be part of the bundle's protected group.
vc
Configures the VC member as individually protected.
Defaults
The VC neither belongs to the bundle's protected group nor is it an individually protected VC.
Command Modes
VC-class configuration (for a VC class).
Bundle-vc configuration (for ATM VC bundle members).
Usage Guidelines
This command first appeared in Release 12.0(3)T.
Use this command in vc-class configuration mode to configure a VC class to contain protected group or individual protected VC status. When the class is applied to the VC bundle member, that VC is characterized by the protected status. You can also apply this command directly to a VC in bundle-vc configuration mode.
When a protected VC goes down, it takes the bundle down. When all members of a protected group go down, the bundle goes down.
To use this command in vc-class configuration mode, enter the vc-class atm global configuration command before you enter this command.
This command has no effect if the VC class that contains the command is attached to a standalone VC, that is, if the VC is not a bundle member.
To use this command in bundle-vc configuration mode, first enter the bundle command to enact bundle configuration mode for the bundle containing the VC member to be configured. Then enter the pvc-bundle configuration command to add the VC to the bundle as a member of it.
VCs in a VC bundle are subject to the following configuration inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode (with effect of assigned VC-class configuration)
•
Subinterface configuration in subinterface mode
Example
The following example configures a class called control-class to include a protect command, which, when applied to a VC bundle member, configures the VC as an individually protected VC bundle member. When this protected VC goes down, it takes the bundle down.
vc-class atm control-classprotect vcRelated Commands
bump
class-vc
precedence (VC bundle)
ubr
ubr+
vbr-nrt
protocol
Use the protocol command in the appropriate command mode to do one or both of the following:
•
Configure a static map for an ATM (permanent virtual circuit) PVC, (switched virtual circuit) SVC, (virtual circuit) VC class, or VC bundle.
•
Enable Inverse ARP or Inverse ARP broadcasts on an ATM PVC by either configuring Inverse ARP directly on the PVC, on the VC bundle, or in a VC class (applies to IP and IPX protocols only).
The no form of this command removes a static map or disables Inverse ARP.
protocol protocol {protocol-address | inarp} [[no] broadcast]
no protocol protocol {protocol-address | inarp} [[no] broadcast]Syntax Description
Default
Inverse ARP is enabled for IP and IPX if the protocol is running on the interface and no static map is configured.
Command Modes
Interface-ATM-VC configuration (for an ATM PVC or SVC).
VC-class configuration (for a VC class).
Bundle configuration (for a VC bundle).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T. For Cisco IOS Release 12.0(3)T, this command has been enhanced to configure a static map for an ATM VC bundle or to enable Inverse ARP or Inverse ARP broadcasts on a VC bundle.
If the protocol command is not explicitly configured on an ATM PVC, SVC, or VC bundle, the VC inherits the following default configuration (listed in order of next highest precedence):
•
Configuration of the protocol ip inarp or protocol ipx inarp command in a VC class assigned to the PVC or SVC itself.
•
Configuration of the protocol ip inarp or protocol ipx inarp command in a VC class assigned to the PVC's or SVC's ATM subinterface.
•
Configuration of the protocol ip inarp or protocol ipx inarp command in a VC class assigned to the PVC's or SVC's ATM main interface.
•
Global default: Inverse ARP is enabled for IP and IPX if the protocol is running on the interface and no static map is configured.
Note
As the inheritance rules imply, when a VC is a member of a VC bundle, configuration using the protocol command in VC-class configuration mode no longer applies to that VC. Bundle configuration takes precedence.
VCs in a VC bundle are subject to the following configuration inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode (with effect of assigned VC-class configuration)
•
Subinterface configuration in subinterface mode
Examples
The following example creates a static map on a VC, indicates that 192.68.34.237 is connected to this VC, and sends ATM pseudobroadcasts:
protocol ip 192.68.34.237 broadcastThe following example enables Inverse ARP for IPX and does not send ATM pseudobroadcasts:
protocol ipx inarp no broadcastThe following example removes a static map from a VC and restores the default behavior for Inverse ARP (refer to the "Default" section):
no protocol ip 192.68.34.237
The following example configures a class called bundle-class to include a protocol command that specifies use of Inverse ARP to resolve IP addresses. This command will be used to configure all of the VC members of a bundle if the bundle-class VC class is applied to the bundle.vc-class atm bundle-class protocol ip inarpRelated Commands
bundle
encapsulation
inarp
oam-bundle
oam retry
ubr
ubr+
vbr-nrtpvc
Use the pvc interface configuration command to do one or more of the following:
•
Create an ATM PVC on a main interface or subinterface.
•
Assign a name to an ATM PVC.
•
Specify ILMI, QSAAL, or SMDS as the encapsulation type on an ATM PVC. (To configure other encapsulations types, see the encapsulation command).
•
Enter interface-ATM-VC configuration mode.
To remove an ATM PVC, use the no form of this command.
pvc [name] vpi/vci [ilmi | qsaal | smds]
no pvc [name] vpi/vci [ilmi | qsaal | smds]Syntax Description
Default
No PVC is defined. When a PVC is defined, the global default of the encapsulation command applies (aal-encap = aal5snap).
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T.
The pvc command replaces the atm pvc command, which, although still supported and available, will be obsoleted in the near future. Use the pvc command to configure a single ATM VC only, not a VC that is a bundle member. We recommend that you use the pvc command in conjunction with the encapsulation and random-detect attach commands instead of the atm pvc command.
The Cisco IOS software dynamically creates rate queues as necessary to satisfy the requests of the pvc commands.
The pvc command creates a PVC and attaches it to the VPI and VCI specified. Both vpi and vci cannot be simultaneously specified as 0; if one is 0, the other cannot be 0.
When configuring an SVC, use the pvc command to configure the PVC that handles SVC call setup and termination. In this case, specify the qsaal keyword. See the second example that follows.
Once you specify a name for a PVC, you can reenter the interface-ATM-VC configuration mode by simply entering pvc name. You can remove a PVC and any associated parameters by entering no pvc name or no pvc vpi/vci.
Note
After configuring the parameters for an ATM PVC, you must exit the interface-ATM-VC configuration mode in order to create the PVC and enable the settings.
If ilmi, qsaal, or smds encapsulation is not explicitly configured on the ATM PVC, the PVC inherits the following default configuration (listed in order of next highest precedence):
•
Configuration of the encapsulation command in a VC class assigned to the PVC itself.
•
Configuration of the encapsulation command in a VC class assigned to the PVC's ATM subinterface.
•
Configuration of the encapsulation command in a VC class assigned to the PVC's ATM main interface.
•
Global default: The global default of the encapsulation command applies. aal-encap = aal5snap.
Examples
The following example creates a PVC with VPI 0 and VCI 16, and communication is set up with the ILMI:
pvc cisco 0/16 ilmiexitThe following example creates a PVC used for ATM signaling for an SVC. It specifies VPI 0 and VCI 5:
pvc cisco 0/5 qsaalexitRelated Commands
atm vc-per-vp
pvc-bundle
To add a virtual circuit (VC) to a bundle as a member of the bundle and enter bundle-vc configuration mode in order to configure that VC bundle member, use the pvc-bundle bundle configuration command. The no form of this command removes the VC from the bundle.
pvc-bundle pvc-name [vpi/] [vci]
no pvc-bundle pvc-name [vpi/] [vci]Syntax Description
Default
None
Command Mode
Bundle configuration
Usage Guidelines
This command first appeared in Release 12.0(3)T.
Each bundle can contain multiple VCs having different QoS attributes. This command associates a VC with a bundle, making it a member of that bundle. Before you can add a VC to a bundle, the bundle must exist. Use the bundle command to create a bundle. You can also use this command to configure a VC that already belongs to a bundle. You enter the command in the same way, giving the name of the VC bundle member.
The pvc-bundle command enters into bundle-vc configuration mode in which you can specify VC-specific and VC class attributes for the VC.
Example
The following example specifies an existing bundle named chicago, and enters into bundle configuration mode. Then, it adds two VCs to the bundle. For each added VC, bundle-vc mode is entered and a VC class is attached to the VC to configure it.
bundle chicago
pvc-bundle chicago-control 207
class control-class
pvc-bundle chicago-premium 206
class premium-classRelated Commands
atm vc-per-vp
bump
class-bundle
class-vc
precedence (VC bundle)
protect
ubr
ubr+
vbr-nrtrandom-detect
To enable per -VC Weighted Random Early Detection (WRED) or per-VC Distributed WRED (DWRED), use the random-detect VC submode command. The no form of this command disables WRED and DWRED for the VC or specified group, if any.
random-detect [attach group-name]
no random-detect [attach group-name]Syntax Description
Default
WRED and DWRED are disabled by default.
Command Mode
VC submode
Usage Guidelines
This command first appeared in Cisco IOS Release 12.0(3)T.
WRED (DWRED) is a congestion avoidance mechanism that slows traffic by randomly dropping packets when congestion exists. WRED (DWRED) is most useful with protocols like TCP that respond to dropped packets by backing off, that is, decreasing the transmission rate. For IP to ATM, WRED and DWRED are configurable at the per-VC levels. The VC level WRED or DWRED configuration will override the interface-level configuration if WRED (or DWRED) is also configured at the interface level.
You can use this command to configure a single ATM VC or a VC that is a member of a bundle. To configure per-VC WRED or per-VC DWRED as a drop policy for the specified WRED or DWRED group, use the attach group-name argument. The random-detect command produces the same results as does the random-detect keyword to the atm pvc command. That is, it specifies that the WRED (or DWRED) algorithm should be applied to the VC. The random-detect attach group-name command, however, attaches the specified group to the VC.
Note
The atm pvc command will be obsoleted in the near future. We recommend that you use the pvc command instead.
When this command is used to configure an interface-level WRED (or DWRED) group to include per-VC WRED (or per-VC DWRED) as a drop policy, the configured WRED (or DWRED) group parameters, including this one, are inherited under the following conditions:
•
All existing VCs—including RSVP SVCs that are not specifically configured with a VC-level WRED (or DWRED) group—will inherit the interface-level WRED or DWRED group parameters.
•
Excepting the VC used for signalling and the Interim Local Management Interface (ILMI) VC, any VCs created after the configuration of an interface-level DWRED group will inherit the parameters.
When an interface-level WRED (or DWRED) group configuration is removed, per-VC WRED or per-VC DWRED parameters are removed from any VC that inherited them from the configured interface-level DWRED group.
When an interface-level WRED (or DWRED) group configuration is modified, per-VC WRED (or DWRED) parameters are modified accordingly if the WRED (or DWRED) parameters were inherited from the configured interface-level WRED (or DWRED) group configuration.
If the WRED (or DWRED) group specified as the attach group-name value does not exist, the VC is configured with default WRED (or DWRED) arguments.
This command is only supported on interfaces that are capable of VC-level queueing. The only currently supported interface is the PA-A3 ATM PA.
To use WRED (or DWRED), Distributed Cisco Express Forwarding (DCEF) switching must first be enabled on the interface. For more information on DCEF, refer to the Cisco IOS Switching Services Configuration Guide and the Cisco IOS Switching Services Command Reference.
The router automatically determines parameters to use in the WRED calculations. To change these parameters, use the precedence command in random-detect-group mode.
The DWRED feature is only supported on Cisco 7000 series routers with an RSP7000 card and Cisco 7500 series routers with a VIP2-40 or higher interface processor. A VIP2-50 interface processor is strongly recommended when the aggregate line rate of the port adapters on the VIP is greater than DS3. A VIP2-50 interface processor is required for OC-3 rates.
Examples
The following example configures per-VC WRED for the pvc called cisco:
pvc cisco 46random-detectThe following part of the example creates a DWRED group called Paris.
RouterA# config terminal RouterA(config)# random-detect-group RomeRouterA(cfg-red-group)# precedence rsvp 1 1 10RouterA(cfg-red-group)# precedence 1 1 2000 30RouterA(cfg-red-group)# precedence 2 1 3000 40RouterA(cfg-red-group)# precedence 3 1 4000 50RouterA(cfg-red-group)# precedence 4 1 3000 60RouterA(cfg-red-group)# precedence 5 1 3000 60RouterA(cfg-red-group)# precedence 6 1 4000 60RouterA(cfg-red-group)# precedence 7 1 4000 60RouterA(cfg-red-group)# exitRouterA(config)# exitThe following example creates a PVC on an ATM interface and applies the WRED group Rome to that PVC:
pvc cisco 46encapsulation aal5snaprandom-detect attach RomeThe following show queueing command displays the current settings for each of the IP Precedences following configuration of per-VC DWRED:
router# show queueing random-detect interface atm 0/0/0 vc 46Current random-detect configuration: VC 0/46 random-detect Rome exponential weight 9class min-threshold max-threshold mark-probability0 - - 1/101 1 2000 1/302 1 3000 1/403 1 4000 1/504 1 3000 1/605 1 3000 1/606 1 4000 1/607 1 4000 1/60rsvp 1 1 1/10Related Commands
random-detect exponential-weighting-constant
random-detect-group
random-detect precedence
show interfaces
show queue
show queueingrandom-detect-group
To define the Weighted Random Early Detection (WRED) or VIP-Distributed WRED (DWRED) parameter group, use the random-detect group global configuration command. The no form of this command deletes the WRED parameter group.
random-detect-group group-name
no random-detect-group group-nameSyntax Description
Default
No WRED /DWRED parameter group exists.
Command Mode
Global configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.1(22)CC.
WRED is a congestion avoidance mechanism that slows traffic by randomly dropping packets when there is congestion. DWRED is similar to WRED but uses the Versatile Interface Processor (VIP) instead of the Route Switch processor (RSP). WRED and DWRED are most useful when the traffic uses protocols such as Transmission Control Protocol (TCP), that respond to dropped packets by decreasing the transmission rate.
The router automatically determines parameters to use in the WRED calculations. If you want to change these parameters for a group, use the exponential-weighting-constant or precedence command.
Example
The following example defines the WRED parameter group sanjose:
random-detect-group sanjoseprecedence 0 32 256 100precedence 1 64 256 100precedence 2 96 256 100precedence 3 128 256 100precedence 4 160 256 100precedence 5 192 256 100precedence 6 224 256 100precedence 7 256 256 100Related Commands
exponential-weighting-constant
precedence (WRED group)
random detect (per VC)
show queueing
show queueing interfaceshow atm bundle
To show the bundle attributes assigned to each bundle virtual circuit (VC) member and the current working status of the VC members, use the show atm bundle privileged EXEC command.
show atm bundle bundle-name
Syntax Description
bundle-name
The name of the bundle whose member information is displayed. This is the bundle name specified by the bundle command when the bundle was created.
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 12.0(3) T.
Sample Display
The following is sample output from the show atm bundle command (* indicates that this VC is the VC for all precedence levels not explicitly configured):
Router# show atm bundlenew-york on atm1/0.1 Status: UP Config. Active Bumping PG/ Peak Avg/Min Burst Name VPI/VCI Preced. Preced. Predec./ PV kbps kbps Cells Status Acceptny-control 0/207 7 7 4 /Yes pv 10000 5000 32 UP ny-premium 0/206 6-5 6-5 7 /No pg 20000 10000 32 UP ny-priority 0/204 4-2 4-2 1 /Yes pg 10000 3000 UP ny-basic* 0/201 1-0 1-0 - /Yes pg 10000 UPlos-angeles on atm1/0.1 - Status: UPConfig. Active Bumping pg/ Peak Avg/Min Burst Name VPI/VCI Preced. Preced. Predec./ pv kbps kbps Cells Status Accept la-high 0/407 7-5 7-5 4 /Yes pv 20000 5000 32 UP la-med 0/404 4-2 4-2 1 /Yes pg 10000 3000 UP la-low* 0/401 1-0 1-0 - /Yes pg 10000 UPsan-francisco on atm1/0.1 - Status: UP Config. Active Bumping pg/ Peak Avg/Min Burst Name VPI/VCI Preced. Preced. Predec./ pv kbps kbps Cells Status Acceptsf-control 0/307 7 7 4/Yes pv 10000 5000 32 UP sf-premium 0/306 6-5 6-5 7/No pg 20000 1000 32 UP sf-priority 0/304 4-2 4-2 1/Yes pg 10000 300 UP sf-basic* 0/301 1-0 1-0 -/Yes pg 10000 UPConfig. Active Bumping pg/ Peak Avg/Min Burst Name VPI/VCI Preced. Preced. Predec./ pv kbps kbps Cells Status Acceptsf-control 0/307 7 7 4/Yes pv 10000 5000 32 UP sf-premium 0/306 6-5 6-5 7/No pg 20000 10000 32 UP sf-priority 0/304 4-2 4-2 1/Yes pg 10000 UP sf-basic* 0/301 1-0 1-0 -/Yes pg 10000 UPRelated Commands
show atm bundle statistics
show atm mapshow atm bundle statistics
To show statistics or detailed statistics on the specified bundle, use the show atm bundle statistics privileged EXEC command.
show atm bundle bundle-name statistics [detail]
Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 12.0(3)T.
Sample Display
The following is sample output from the show atm bundle statistics command:
Router# show atm bundle san-jose statisticsBundle Name: Bundle State: UPAAL5-NLPID OAM frequency : 0 second(s), OAM retry frequency: 1 second(s)OAM up retry count: 3, OAM down retry count: 5BUNDLE is not managed.InARP frequency: 15 minute(s)InPkts: 3, OutPkts: 3, Inbytes: 1836, Outbytes: 1836 InPRoc: 3, OutPRoc: 0, Broadcasts: 3InFast: 0, OutFast: 0, InAS: 0, OutAS: 0Router# show atm bundle san-jose statistics detailBundle Name: Bundle State: UPAAL5-NLPIDOAM frequency: 0 second(s), OAM retry frequency: 1 second(s)OAM up retry count: 3, OAM down retry count: 5BUNDLE is not managed.InARP frequency: 15 minute(s)InPkts: 3, OutPkts: 3, InBytes; 1836, OutBytes: 1836InPRoc: 3, OutPRoc: 0, Broadcasts: 3InFast: 0, OutFast: 0, InAS: 0, OutAS: 0ATM1/0.52: VCD: 6, VPI: 0 VCI: 218, Connection Name: sj-basic UBR, PeakRate: 155000 AAL5-LLC/SNAP, etype:0x0, Flags: 0xC20, VCmode: 0xE00OAM frequency: 0 second(s), OAM retry frequency: 1 second(s)OAM up retry count: 3, OAM down retry count: 5OAM Loopbavk status: OAM DisabledOMA VC state: Not ManagedILMI VC state: Not ManagedInARP frequency: 15 minute(s)InPkts: 3, OutPkts: 3, InBytes; 1836, OutBytes: 1836InPRoc: 3, OutPRoc: 0,Broadcasts: 3InFast: 0, OutFast: 0, InAS: 0, OututAS: 0OAM cells received: 0F5 InEndloop: 0, F5 InSegloop: 0, F5 InAIS: 0, F5 InRDI: 0F4 InEndloop: 0, F4 OutSegloop:0, F4 InAIS: 0, F4 InRDI: 0OAM cells sent: 0F5 OutEndloop: 0. F5 OutSegloop: 0, f5 Out RDI:0F4 OutEndloop: 0, F4 OutSegloop: 0, F4 OUtRDI: 0OAM cell drops: 0Status; UPATM1/0.52: VCD: 4, VPI: 0 VCI: 216, Connection Name: sj-premiumUBR, PeakRate: 155000AAL5-LLC/SNAP, etype: 0x0, Flags: 0xC20, VCmode: 0xE000OAM frequency: 0 second(s), OAM retry frequency: 1 second(s)OAM up retry count: 3, OAM down retry count: 5OAM Loopback status: OAM DisabledOAM VC state: Not ManagedILMI VC state: Not Managed InARP frequency: 15 minute(s)InPkts: 0, OutPkts: 0, InBytes; 0, OutBytes: 0InPRoc: 0, OutPRoc: 0,Broadcasts: 0InFast: 0, OutFast: 0, InAS: 0 OAM cells received: 0F5 InEndloop: 0, F4 InSegloop: 0, F4InAIS; 0, F4 InRDI: 0F4 OutEndloop: 0, F4 OutSegloop: F4 OutRDI: 0OAM cell drops: 0Status: UPRelated Commands
show atm bundle
show atm map
show atm map
To show the list of all configured ATM static maps to remote hosts on an ATM network and on ATM bundle maps, use the show atm map privileged EXEC command.
show atm map
Syntax Description
This command has no arguments or keywords.
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command was modified in Cisco IOS Release 11.1CA to include a sample display for the ATM-CES port adapter (PA).
This command was modified in Cisco IOS Release 12.0(3)T to include display for ATM bundle maps. An ATM bundle map identifies a bundle and all of its related VCs.
Sample Displays
The following is sample output from the show atm map command for a bundle called san-jose (0/122, 0/123, 0/124, and 0/126 are the virtual path and virtual channel identifiers of the bundle members):
Router# show atm mapMap list san-jose_B_ATM1/0.52 : PERMANENT ip 1.1.1.1. maps to bundle san-jose, 0/122, 0/123, 0/124, 0/126, ATM1/0.52, broadcastThe following is sample output from the show atm map command for an ATM-CES PA on the Cisco 7200 series router:
Router# show atm mapMap list alien: PERMANENTip 128.1.1.1 maps to VC 6ip 128.1.1.2 maps to VC 6The following is sample output from the show atm map command that displays information for a bundle called new-york:
Router# show atm mapMap list atm:vines 3004B310:0001 maps to VC 4, broadcastip 172.21.168.110 maps to VC 1, broadcastclns 47.0004.0001.0000.0c00.6e26.00 maps to VC 6, broadcastappletalk 10.1 maps to VC 7, broadcastdecnet 10.1 maps to VC 2, broadcast Map list new-york: PERMANENT ip 10.0.0.2 maps to bundle new-york, 0/200, 0/205, 0/210, ATM1/0.1The following is sample output from the show atm map command for a multipoint connection:
Router# show atm mapMap list atm_pri: PERMANENTip 4.4.4.4 maps to NSAP CD.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12, broadcast, aal5mux, multipoint connection up, VC 6ip 4.4.4.6 maps to NSAP DE.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12, broadcast, aal5mux, connection up, VC 15, multipoint connection up, VC 6Map list atm_ipx: PERMANENTipx 1004.dddd.dddd.dddd maps to NSAP DE.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12, broadcast, aal5mux, multipoint connection up, VC 8ipx 1004.cccc.cccc.cccc maps to NSAP CD.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12, broadcast, aal5mux, multipoint connection up, VC 8Map list atm_apple: PERMANENTappletalk 62000.5 maps to NSAP CD.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12, broadcast, aal5mux, multipoint connection up, VC 4appletalk 62000.6 maps to NSAP DE.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12, broadcast, aal5mux, multipoint connection up, VC 4The following is sample output from the show atm map command if you configure an ATM PVC using the pvc command:
Router# show atm mapMap list endA: PERMANENTip 148.11.11.1 maps to VC 4, VPI 0, VCI 60, ATM0.2describes the fields shown in the displays.
Related Commands
show atm bundle
show atm bundle statshow queueing interface
To show the queueing statistics of an interface, use the show queueing interface privileged EXEC command.
show queueing interface interface-number [vc [[vpi/] vci]]
Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 11.1(22)CC.
Related Commands
atm pvc
exponential-weighting-constant
precedence (WRED group)
random-detect-group
show queueing
show queueing redshow queueing red
To show the configured weighted random early detection (WRED) parameters, use the show queueing red privileged EXEC command.
show queueing red [interface atm_subinterface [vc[[vpi/] vci]]]
Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 11.1(22)CC.
If no keyword is entered, this command displays the parameters of every WRED-enabled VC on every ATM interface in the system.
Related Commands
atm pvc
exponential-weighting-constant
precedence (WRED group)
random-detect-group
show queueing
show queueing interfaceubr
To configure unspecified bit rate (UBR) quality of service (QoS) and specify the output peak cell rate (PCR) for an ATM permanent virtual circuit (PVC), switched virtual circuit (SVC), virtual circuit (VC) class, or VC bundle member, use the ubr command in the appropriate command mode. The no form of this command removes the UBR parameter.
ubr output-pcr [input-pcr]
no ubr output-pcr [input-pcr]Syntax Description
Default
UBR QoS at the maximum line rate of the physical interface.
Command Modes
Interface-ATM-VC configuration (for an ATM PVC or SVC).
VC-class configuration (for a VC class).
Bundle-vc configuration (for ATM VC bundle members).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T.
For Cisco IOS Release 12.0(3)T, this command has been enhanced to support selection of UBR QoS and configuration of output PCR for ATM VC bundles and ATM VC bundle members.
To configure ATM SVCs with an output PCR and an input PCR that differ from each other, you must expressly configure an output value and an input value using the output-pcr and input-pcr arguments, respectively.
Configure QoS parameters using the ubr, ubr+, or vbr-nrt command. The last command you enter will apply to the PVC or SVC you are configuring.
If the ubr command is not explicitly configured on an ATM PVC, SVC, or VC bundle member, the VC inherits the following default configuration (listed in order of next highest precedence):
•
Configuration of any QoS command (ubr, ubr+, or vbr-nrt) in a VC class assigned to the PVC or SVC itself.
•
Configuration of any QoS command (ubr, ubr+, or vbr-nrt) in a VC class assigned to the PVC's or SVC's ATM subinterface.
•
Configuration of any QoS command (ubr, ubr+, or vbr-nrt) in a VC class assigned to the PVC's or SVC's ATM main interface.
•
Global default: UBR QoS at the maximum line rate of the PVC or SVC.
To use this command in VC-class configuration mode, enter the vc-class atm global configuration command. This command has no effect if the VC class that contains the command is attached to a standalone VC, that is, if the VC is not a bundle member.
To use this command in bundle-vc configuration mode, first enter the bundle command to specify the bundle, then enter bundle configuration mode. Then enter the pvc-bundle configuration command to add the VC to the bundle as a member of it and enter bundle-vc configuration mode.
VCs in a VC bundle are subject to the following configuration inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode (with effect of assigned VC-class configuration)
•
Subinterface configuration in subinterface mode
Examples
The following example specifies the output-pcr for an ATM PVC to be 100,000 kbps:
pvc 1/32ubr 100000The following example specifies the output-pcr and input-pcr for an ATM SVC to be 10,000 kbps and 9000 kbps, respectively:
svc lion nsap 47.0091.81.000000.0040.0B0A.2501.ABC1.3333.3333.05ubr 10000 9000Related Commands
abr
broadcast
bump
bundle
class
encapsulation
inarp
oam-bundle
oam-retry
precedence
protect
protocol
pvc-bundle
ubr+
vbr-nrt
ubr+
To configure unspecified bit rate (UBR) quality of service (QoS) and specify the output peak cell rate and output minimum guaranteed cell rate for an ATM permanent virtual circuit (PVC), switched virtual circuit (SVC), virtual circuit (VC) class, or VC bundle member, use the ubr+ command in the appropriate command mode. The no form of this command removes the UBR+ parameters.
ubr+ output-pcr output-mcr [input-pcr] [input-mcr]
no ubr+ output-pcr output-mcr [input-pcr] [input-mcr]Syntax Description
Default
UBR QoS at the maximum line rate of the physical interface.
Command Modes
Interface-ATM-VC configuration (for an ATM PVC or SVC).
VC-class configuration (for a VC class).
Bundle-vc configuration (for ATM VC bundle members).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T.
For Cisco IOS Release 12.0(3)T, this command has been enhanced to support selection of UBR+ QoS and configuration of output PCR and output minimum guaranteed cell rate ATM VC bundles, and VC bundle members.
To configure ATM SVCs with an output PCR and an input PCR that differ from each other, you must expressly configure an output value and an input value using the output-pcr, output-mcr, input-pcr, and input-mcr arguments, respectively.
Configure QoS parameters using the ubr, ubr+, or vbr-nrt command. The last command you enter will apply to the PVC or SVC you are configuring.
If the ubr+ command is not explicitly configured on an ATM PVC or SVC, the VC inherits the following default configuration (listed in order of next highest precedence):
•
Configuration of any QoS command (ubr, ubr+, or vbr-nrt) in a VC class assigned to the PVC or SVC itself.
•
Configuration of any QoS command (ubr, ubr+, or vbr-nrt) in a VC class assigned to the PVC's or SVC's ATM subinterface.
•
Configuration of any QoS command (ubr, ubr+, or vbr-nrt) in a VC class assigned to the PVC's or SVC's ATM main interface.
•
Global default: UBR QoS at the maximum line rate of the PVC or SVC.
To use this command in VC-class configuration mode, enter the vc-class atm global configuration command before you enter the ubr+ command. This command has no effect if the VC class that contains the command is attached to a standalone VC, that is, if the VC is not a bundle member.
To use this command in bundle-vc configuration mode, first enter the bundle command to specify the bundle the VC member belongs to, then enter bundle configuration mode. Then enter the pvc-bundle bundle configuration command to add the VC to the bundle as a member of it.
VCs in a VC bundle are subject to the following configuration inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode (with effect of assigned VC-class configuration)
•
Subinterface configuration in subinterface mode
Examples
The following example specifies the output-pcr for an ATM PVC to be 100,000 kbps and the output-mcr to be 3000 kbps:
pvc 1/32ubr+ 100000 3000The following example specifies the output-pcr, output-mcr, input-pcr, and input-mcr for an ATM SVC to be 10,000 kbps, 3000 kbps, 9000 kbps, and 1000 kbps, respectively:
svc lion nsap 47.0091.81.000000.0040.0B0A.2501.ABC1.3333.3333.05ubr+ 10000 3000 9000 1000Related Commands
abr
broadcast
bump
bundle
class
encapsulation
inarp
oam-bundle
oam-retry
precedence
protect
protocol
pvc-bundle
ubr
vbr-nrtvbr-nrt
To configure the variable bit rate-nonreal time (VBR-NRT) quality of service (QoS) and specify output peak cell rate (PCR), output sustainable cell rate, and output maximum burst cell size for an ATM permanent virtual circuit (PVC), switched virtual circuit (SVC), virtual circuit (VC) class, or VC bundle member, use the vbr-nrt command in the appropriate command mode. The no form of this command removes the VBR-NRT parameters.
vbr-nrt output-pcr output-scr output-mbs [input-pcr] [input-scr] [input-mbs]
no vbr-nrt output-pcr output-scr output-mbs [input-pcr] [input-scr] [input-mbs]Syntax Description
Default
UBR QoS at the maximum line rate of the physical interface.
Command Modes
Interface-ATM-VC configuration (for an ATM PVC or SVC).
VC-class configuration (for a VC class).
Bundle-vc configuration (for ATM VC bundle members).
Usage Guidelines
This command first appeared in Cisco IOS Release 11.3 T.
For Cisco IOS Release 12.0(3)T, this command has been enhanced to support configuration of VBR-NRT QoS and specification of output PCR, output SCR, and output maximum burst cell size for ATM bundles and VC bundle members.
Configure QoS parameters using the ubr, ubr+ or vbr-nrt command. The last command you enter will apply to the PVC or SVC you are configuring.
If the vbr-nrt command is not explicitly configured on an ATM PVC or SVC, the VC inherits the following default configuration (listed in order of next highest precedence):
•
Configuration of any QoS command (ubr, ubr+, or vbr-nrt) in a VC class assigned to the PVC or SVC itself.
•
Configuration of any QoS command (ubr, ubr+, or vbr-nrt) in a VC class assigned to the PVC's or SVC's ATM subinterface.
•
Configuration of any QoS command (ubr, ubr+, or vbr-nrt) in a VC class assigned to the PVC's or SVC's ATM main interface.
•
Global default: UBR QoS at the maximum line rate of the PVC or SVC.
To use this command in VC-class configuration mode, enter the vc-class atm global configuration command before you enter the vbr-nrt command. This command has no effect if the VC class that contains the command is attached to a standalone VC, that is, if the VC is not a bundle member.
To use this command in bundle-vc configuration mode, first enter the pvc-bundle configuration command to add the VC to the bundle as a member of it, then and enter bundle-vc configuration mode.
VCs in a VC bundle are subject to the following configuration inheritance rules (listed in order of next highest precedence):
•
VC configuration in bundle-vc mode
•
Bundle configuration in bundle mode (with effect of assigned VC-class configuration)
•
Subinterface configuration in subinterface mode
Examples
The following example specifies the output-pcr for an ATM PVC to be 100,000 kbps, the output-scr to be 50,000 kbps, and the output-mbs to be 64:
pvc 1/32vbr-nrt 100000 50000 64The following example specifies the VBR-NRT output and input parameters for an ATM SVC:
svc lion nsap 47.0091.81.000000.0040.0B0A.2501.ABC1.3333.3333.05vbr-nrt 10000 5000 32 20000 10000 64Related Commands
abr
broadcast
bump
bundle
class
encapsulation
inarp
oam-bundle
oam-retry
precedence
protect
protocol
pvc-bundle
ubr
ubr+






