Table Of Contents
Mobile Ad Hoc Networks for Router-to-Radio Communications
Finding Feature Information
Contents
Prerequisites for Mobile Ad Hoc Networks for Router-to-Radio Communications
Restrictions for Mobile Ad Hoc Networks for Router-to-Radio Communications
Information About Mobile Ad Hoc Networks for Router-to-Radio Communications
Benefits of Router-to-Radio Links Using Virtual Multipoint Interfaces with PPPoE in Cisco IOS Software
MANETs for Router-to-Radio Communications
PPPoE Interfaces for Mobile Radio Communications
Virtual Multipoint Interface
Link Quality Metrics Reporting for OSPFv3 and EIGRP with VMI Interfaces
OSPF Cost Calculation for VMI Interfaces
EIGRP Cost Metrics for VMI Interfaces
VMI Metric to EIGRP Metric Conversion
Dynamic Cost Metric for VMI Interfaces
EIGRP Metric Dampening for VMI Interfaces
Neighbor Up/Down Signaling for OSFPv3 and EIGRP
PPPoE Credit-based Flow Control
IPv6 Addresses
Restrictions for IPv6 Addressing
Multicast Support for VMI Interfaces
How to Configure Router-to-Radio Links Using VMI PPPoE
Creating a Subscriber Profile for PPPoE Service Selection
Configuring the PPPoE Profile for PPPoE Service Selection
Configuring PPPoE on an Ethernet Interface
Creating and Configuring a Virtual Template for VMI PPPoE
Creating and Configuring a VMI Interface for EIGRP IPv4
Creating and Configuring a VMI interface for EIGRP IPv6
Setting the EIGRP Change-based Dampening Interval for VMI Interfaces using classic-style configuration
Setting the EIGRP Change-based Dampening Interval for VMI Interfaces using named-style configuration
Setting the EIGRP Interval-based Dampening Interval for VMI Interfaces using classic-style configuration
Setting the EIGRP Interval-based Dampening Interval for VMI Interfaces using named-style configuration
Enabling Multicast Support on a VMI Interface
Creating and Configuring a VMI Interface for OSPFv3
Verifying the VMI Configuration
Configuration Examples for VMI PPPoE
Basic VMI PPPoE Configuration with EIGRP IPv4: Example
Basic VMI PPPoE Configuration Using EIGRP for IPv6: Example
VMI PPPoE Configuration Using EIGRP for IPv4 and IPv6: Example
EIGRP Metric Dampening for VMI Interfaces: Examples
Dampening-change command
Dampening-interval command
EIGRP Change-based Dampening for VMI Interfaces: Example
EIGRP Interval-based Dampening for VMI Interfaces: Example
VMI PPPoE Configuration for OSPFv3: Example
VMI PPPoE Configuration Using Multiple Virtual Templates: Example
Enabling Multicast Support on a VMI Interface: Examples
PPPoE Configuration: Example
Configuring Two VMIs: Example
Marking and Queuing Packets over VMI: Example
Additional References
Related Documents
Standards
MIBs
RFCs
Technical Assistance
Feature Information About the Mobile Ad Hoc Networks for Router-to-Radio Communications
Mobile Ad Hoc Networks for Router-to-Radio Communications
First Published: May 17, 2007
Last Updated: October 2, 2009
Mobile Ad Hoc Networks (MANET) for router-to-radio communications address the challenges faced when merging IP routing and mobile radio communications in ad hoc networking applications. the Cisco solution for MANETs provides capabilities that enable
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Optimal route selection based on Layer 2 feedback from the radio network
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Faster convergence when nodes join and leave the network
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Efficient integration of point-to-point, directional radio topologies with multi hop routing
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Flow-controlled communications between each radio and its partner router
Through the router-to-radio link, the radio can inform the router immediately when a node joins or leaves, and this enables the router to recognize topology changes more quickly than if it had to rely on timers. Without this link-status notification from the radio, the router would likely time out while waiting for traffic. The link-status notification from the radio enables the router to respond faster to network topology changes. Metric information regarding the quality of a link is passed between the router and radio, enabling the router to more intelligently decide on which link to use.
With the link-status signaling provided by the router-to-radio link, applications such voice and video work better because outages caused by topology changes are reduced or eliminated. Sessions are more stable and remain active longer.
Finding Feature Information
Your Cisco IOS software release may not support all of the features documented in this module. To reach links to specific feature documentation in this module and to see a list of the releases in which each feature is supported, use the "Feature Information About the Mobile Ad Hoc Networks for Router-to-Radio Communications" section.
Use Cisco Feature Navigator to find information about platform support and Cisco IOS and Catalyst OS software image support. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Contents
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Prerequisites for Mobile Ad Hoc Networks for Router-to-Radio Communications
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Restrictions for Mobile Ad Hoc Networks for Router-to-Radio Communications
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Information About Mobile Ad Hoc Networks for Router-to-Radio Communications
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How to Configure Router-to-Radio Links Using VMI PPPoE
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Configuration Examples for VMI PPPoE
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Additional References
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Feature Information About the Mobile Ad Hoc Networks for Router-to-Radio Communications
Prerequisites for Mobile Ad Hoc Networks for Router-to-Radio Communications
The features described in this document require one of the following router platforms:
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Cisco 2800 Series (2801, 2811, 2821, or 2851)
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Cisco 3250 and Cisco 3270
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Cisco 3800 Series (3825 or 3845)
To use the PPPoE and virtual multipoint interface (VMI) features described in this document, a radio device that implements the PPPoE functionality enhancements described in the draft RFC 2516 is required. Users can optionally implement draft-bberry-pppoe-credit-06.txt for PPP Over Ethernet (PPPoE) Extensions for Credit Flow and Link Metrics, but this draft must be implemented if you plan to use VMI features.
Restrictions for Mobile Ad Hoc Networks for Router-to-Radio Communications
VMI on Routed Ports
VMIs can be configured only on routed ports. VMIs are not supported on VLAN or switched ports.
Quality of Service
Of the Quality of Service (QoS) queueing features available from Cisco, only class-based Weighted Fair Queueing (WFQ) is supported on VMIs. The VMI can identify Differentiated Services Code Point (DSCP) values, and perform network-based application recognition (NBAR), but no policing or policy mapping occurs on those matches.
Information About Mobile Ad Hoc Networks for Router-to-Radio Communications
This section describes VMI PPPoE. The following sections are included:
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Benefits of Router-to-Radio Links Using Virtual Multipoint Interfaces with PPPoE in Cisco IOS Software
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MANETs for Router-to-Radio Communications
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IPv6 Addresses
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PPPoE Interfaces for Mobile Radio Communications
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Link Quality Metrics Reporting for OSPFv3 and EIGRP with VMI Interfaces
Benefits of Router-to-Radio Links Using Virtual Multipoint Interfaces with PPPoE in Cisco IOS Software
As the global leader in mission-critical networking and IP communications, Cisco is uniquely positioned to deliver reliable and efficient converged voice, video, and data solutions to organizations around the world. Benefits of this technology include the following:
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Optimal route selection is based on Layer 2 feedback from the radio network.
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Efficient integration of point-to-point, directional radio topologies with multi hop routing.
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Convergence is faster when nodes join and leave the network because routers are able to respond faster to network topology changes.
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Flow-controlled communications between the radio and its partner router enables applications such voice and video to work better because outages caused by moving links are reduced or eliminated. Sessions are more stable and remain active longer.
MANETs for Router-to-Radio Communications
Mobile Ad Hoc Networks (MANETs) enable users deployed in areas with no fixed communications infrastructure to access critical voice, video, and data services. Soldiers in the field can employ unified communications, multimedia applications, and real-time information dissemination to improve situational awareness and respond quickly to changing battlefield conditions. Disaster managers can use video conferences, database access, and collaborative tools to coordinate multi-agency responses within an Incident Command System (ICS) framework. For event planners and trade show managers, MANETs represent a cost-effective way to accommodate mobile end users on a short term basis. MANETs set the stage for more timely information sharing and faster, more effective decision-making.
In MANET environments, highly mobile nodes communicate with each other across bandwidth-constrained radio links. An individual node includes both a radio and a network router, with the two devices interconnected over an Ethernet. Since these nodes can rapidly join or leave the network, MANET routing topologies are highly dynamic. Fast convergence in a MANET becomes a challenge because the state of a node can change well before the event is detected by the normal timing mechanisms of the routing protocol.
Radio link quality in a MANET can vary dramatically because it can be affected by a variety of factors such as noise, fading, interference, and power fluctuation. As a result, avoiding congestion and determining optimal routing paths also pose significant challenges for the router network. Finally, directional radios that operate on a narrow beam tend to model the network as a series of physical point-to-point connections with neighbor nodes. This point-to-point model does not translate gracefully to multi-hop, multipoint router environments, as it increases the size of each router's topology database and reduces routing efficiency.
Effective networking in a MANET environment therefore requires mechanisms by which
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routers and radios can interoperate efficiently, and without impacting operation of the radio network
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radio point-to-point and router point-to-multipoint paradigms can be rationalized
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radios can report status to routers for each link and each neighbor, and
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routers can use this information to optimize routing decisions.
PPPoE Interfaces for Mobile Radio Communications
The Cisco MANET solution employs PPP-over-Ethernet (PPPoE) sessions to enable intra-nodal communications between a router and its partner radio. Each radio initiates the PPPoE session as soon as the radio establishes a radio link to another radio. After the PPPoE sessions are active, a PPP session is established end-to-end (router-to-router); This is duplicated each time a radio establishes a new radio link. The Virtual Multipoint Interface (VMI) on the router aggregates multiple PPPoE sessions and multiplexes these to look like a single interface to the routing processes. This interface collects the series of PPP/PPPoE connections. Underneath the VMI interface there are virtual access interfaces that are associated with each of the PPP/PPPoE connections.
A PPPoE session is established between a router and a radio on behalf of every other router/radio neighbor located in the MANET. These Layer 2 sessions are the means by which radio network status gets reported to the Layer 3 processes in the router. Figure 1 illustrates the PPPoE session exchange between mobile routers and directional radios in a MANET network.
Figure 1 PPPoE Session Exchange Between Mobile Routers and Directional Radios
This capability assumes that a PPPoE-equipped radio connects to a router using Ethernet. The router always considers the Ethernet link to be up. If the radio side of the link goes down, the router will wait until a routing update time-out has occurred to declare the route down and then update the routing table. Figure 2 illustrates a simple router-to-radio link topology.
Figure 2 Router-to-Radio Link
Routing protocols used for VMI PPPoE are EIGRP (IPv4, IPv6) and OSPFv3 (IPv6).
Virtual Multipoint Interface
The VMI interface provides services that map outgoing packets to the appropriate PPPoE sessions based on the next-hop forwarding address for that packet. The VMI interface also provides a broadcast service that emulates a set of point-to-point connections as a point-to-multipoint interface with broadcast ability. When a packet with a multicast address is forwarded through the VMI interface, VMI replicates the packet and unicasts it to each of its neighbors.
Directional radios are frequently used in applications that require greater bandwidth, increased power-to-transmission range, or reduced probability of detection. These radios operate in a point-to-point mode, and generally have no broadcast capability. On the other hand, the routing processes in Cisco's MANET solution operate most efficiently when viewing the network link as point-to-multipoint, with broadcast capability. For the router, modeling the MANET as a collection of point-to-point nodes would have a dramatic impact on the size of its internal database.
The Virtual Multipoint Interface (VMI) within the router aggregates all of the per-neighbor PPPoE sessions from the Radio Ethernet connection. The VMI maps the sessions to appear to Layer 3 routing protocols and applications as a single point-to-multipoint, multi-access, broadcast-capable network. However, the VMI preserves the integrity of the PPPoE sessions on the radio side, so that each point-to-point connection can have its own Quality of Service (QoS) queue.
The VMI also relays the link quality metric and neighbor up/down signaling from the radio to the routing protocols. Currently, VMI signals are used by EIGRP (for IPv4 and IPv6 neighbors) and OSPFv3 (for IPv6 neighbors).
Link Quality Metrics Reporting for OSPFv3 and EIGRP with VMI Interfaces
The quality of a radio link has a direct impact on the throughput that can be achieved by router-router traffic. The PPPoE protocol has been extended to provide a process by which a router can request, or a radio can report, link quality metric information. Cisco's OSFPv3 and EIGRP implementations have been enhanced so that the route cost to a neighbor is dynamically updated based on metrics reported by the radio, thus allowing the best route to be chosen within a given set of radio links.
The routing protocols receive raw radio link data, and compute a composite quality metric for each link. In computing these metrics, the following factors may be considered:
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Maximum Data Rate - the theoretical maximum data rate of the radio link, in bytes per second
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Current Data Rate - the current data rate achieved on the link, in bytes per second
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Latency - the transmission delay packets encounter, in milliseconds
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Resources - a percentage (0-100) that can represent the remaining amount of a resource (such as battery power)
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Relative Link Quality - a numeric value (0-100) representing relative quality, with 100 being the highest quality
Metrics can be weighted during the configuration process to emphasize or de-emphasize particular characteristics. For example, if throughput is a particular concern, the current data rate metric could be weighted so that it is factored more heavily into the composite metric. Similarly, a metric that is of no concern can be omitted from the composite calculation.
Link metrics can change rapidly, often by very small degrees, which could result in a flood of meaningless routing updates. In a worst case scenario, the network would be churning almost continuously as it struggled to react to minor variations in link quality. To alleviate this concern, Cisco provides a tunable dampening mechanism that allows the user to configure threshold values. Any metric change that falls below the threshold is ignored.The quality of a connection to a neighbor varies, based on various characteristics of the interface when OSPF or EIGRP is used as the routing protocol. The routing protocol receives dynamic raw radio link characteristics and computes a composite metric that is used to reduce the effect of frequent routing changes.
A tunable hysteresis mechanism allows users to adjust the threshold to the routing changes that occur when the router receives a signal that a new peer has been discovered, or that an existing peer is unreachable. The tunable metric is weighted and is adjusted dynamically to account for the following characteristics:
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Current and Maximum Bandwidth
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Latency
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Resources
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Hysteresis
Individual weights can be deconfigured and all weights can be cleared so that the cost is set back to the default value for the interface type. Based on the routing changes that occur, cost can be determined by the application of these metrics. The following sections provide more details about OSPF and EIGRP metrics:
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OSPF Cost Calculation for VMI Interfaces
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EIGRP Cost Metrics for VMI Interfaces
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VMI Metric to EIGRP Metric Conversion
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Dynamic Cost Metric for VMI Interfaces
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EIGRP Metric Dampening for VMI Interfaces
OSPF Cost Calculation for VMI Interfaces
Because cost components can change rapidly, it might be necessary to dampen the volume of changes to reduce network-wide churn. The recommended values for S2, S3, and S4 are based on network simulations that may reduce the rate of network changes. The recommended value for S1 is zero to eliminate this variable from the route cost calculation.
The overall link cost is computed using the following formula:
Table 1 defines the symbols used in the OSPF cost calculation.
Table 1 OSPF Cost Calculation Definitions
Cost Component
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Component Definition
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OC
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The "default OSPF Cost". Calculated from reference bandwidth using
reference_bw / (MDR*1000) where reference_bw=10^8
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A through D
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Various radio-specific data based formula's which produce result in range 0-64k
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A
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CDR and MDR related formula
(2^16 * (100 - (CDR * 100 / MDR)))/100
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B
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Resources related formula
((100 - RESOURCES)^3 * 2^16 / 10^6)
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C
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Latency as reported by the radio (already in the 0-64K range when reported (LATENCY)
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D
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RLF related formula
((100 - RLF) * 2^16)/100
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S1 through S4
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Scalar weighting factors input from CLI. These scalars scale DOWN the values as computed by A-D.
The value of 0 disables and value of 100 enables full 0-64k range for one component.
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While each network might have unique characteristics that require different settings to optimize actual network performance, these are recommended values intended as a starting point for optimizing a OSPFv3 network. Table 2 lists the recommended value settings for OSPF cost metrics.
Table 2 Recommended Value Settings for OSPF Cost Metrics
Setting
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Metric Description
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Default Value
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Recommended Value
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S1
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ipv6 ospf dynamic weight throughout
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100
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0
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S2
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ipv6 ospf dynamic weight resources
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100
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29
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S3
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ipv6 ospf dynamic weight latency
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100
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29
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S4
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ipv6 ospf dynamic weight L2 factor
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100
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29
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Using this formula, the default path costs were calculated as noted in the following list. If these values do not suit your network, you can use your own method of calculating path costs.
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56-kbps serial link—Default cost is 1785.
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64-kbps serial link—Default cost is 1562.
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T1 (1.544-Mbps serial link)—Default cost is 64.
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E1 (2.048-Mbps serial link)—Default cost is 48.
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4-Mbps Token Ring—Default cost is 25.
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Ethernet—Default cost is 10.
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16-Mbps Token Ring—Default cost is 6.
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FDDI—Default cost is 1.
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X25—Default cost is 5208.
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Asynchronous—Default cost is 10,000.
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ATM— Default cost is 1.
To illustrate these settings, the following example shows how OSPF cost metrics might be defined for a VMI interface:
ipv6 ospf cost dynamic weight throughput 0
ipv6 ospf cost dynamic weight resources 29
ipv6 ospf cost dynamic weight latency 29
ipv6 ospf cost dynamic weight L2-factor 29
EIGRP Cost Metrics for VMI Interfaces
When EIGRP is used as the routing protocol, metrics allow EIGRP to respond to routing changes. The link-state metric is advertised as the link cost in the router link advertisement.The reply sent to any routing query will always contain the latest metric information. Exceptions which will result in immediate update being sent:
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A down interface
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A down route
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Any change in metric which results in the router selecting a new next hop
EIGRP receives dynamic raw radio link characteristics and computes a composite EIGRP metric based on a proprietary formula. To avoid churn in the network as a result of the change in the link characteristics, a tunable dampening mechanism is used.
EIGRP uses the metric weights along with a set of vector metrics to compute the composite metric for local RIB installation and route selections. The EIGRP composite metric is calculated using the formula:
EIGRP Metric = 256*((K1*Bw) + (K2*Bw)/(256-Load) + (K3*Delay)*(K5/(Reliability + K4)))
Table 3 lists the EIGRP vector metrics and their descriptions.
Table 3 EIGRP Vector Metrics
Vector Metric
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Description
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bandwidth
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Minimum bandwidth of the route in kilobits per second. It can be 0 or any positive integer. The bandwidth for the formula is scaled and inverted by the following formula:
(10^7/minimum Bw in kilobits per second)
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delay
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Route delay in tens of microseconds.
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delay reliability
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Likelihood of successful packet transmission expressed as a number between 0 and 255. The value 255 means 100 percent reliability; 0 means no reliability.
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load
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Effective load of the route expressed as a number from 0 to 255 (255 is 100 percent loading).
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mtu
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Minimum maximum transmission unit (MTU) size of the route in bytes. It can be 0 or any positive integer.
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EIGRP monitors metric weights on an interface to allow for the tuning of EIGRP metric calculations and indicate type of service (TOS). Table 4 lists the K-values and their default.
Table 4 EIGRP K-Value Defaults
Setting
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Default Value
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K1
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1
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K2
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0
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K3
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1
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K4
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0
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K5
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0
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Most configurations use the first two metrics -delay and bandwidth, with bandwidth taking precedence. The default formula of 256*(BW +Delay) is the EIGRP metric. The bandwidth for the formula is scaled and inverted by the following formula:
(10^7/minimum Bw in kilobits per second)
Note
You can change the weights (as with IGRP), but these weights must be the same on all the routers.
For example, look at an IGRP link whose bandwidth to a particular destination is 128k and the delay is 84000 microseconds.
Using the cut-down formula, the EIGRP metric calculation would simplify to 256*(BW + Delay), resulting in the following value:
Metric = 256*(10^7/128 + 84000/10)= 256*86525 = 22150400
To calculate route delay, divide the delay value by 10 to get the true value in tenths of microseconds
When calcluating the delay for MANET and the delay is obtained from a router interface, it is always calculated in tens of microseconds. In most cases, when using MANET, you will not use the interface delay, but rather the delay that is advertised by the radio. The delay you will receive from the radio is in microseconds, so you must adjust the cut-down formula as follows:
Metric = (256*(10^7/128) + (84000*256)/10) = 20000000 + 2150400 = 22150400
VMI Metric to EIGRP Metric Conversion
The quality of connection to a VMI neighbor will vary based on various characteristics computed dynamically based on the feedback from L2 to L3. Table 5 lists the EIGRP metrics and their significance.
Table 5 EIGRP MANET Metrics for VMI Interfaces
Metric
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Significance
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current data rate
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Snapshot value of bytes per second rate on the link
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max data rate
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Bytes per second maximum rate on link
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latency
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Average delay on the link, specified in ms
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resources
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A representation of resources indicating a percentage (0-100), such as, battery power. Harris implementation always reports 100
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relative link quality
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opaque number (0-100) representing radio's view of link quality 0 represents the worst possible link, 100 represents the best.
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These EIGRP vector metric values map to the basic EIGRP interface parameters as indicated in Table 6
Table 6 Mapping of VMI Metric Values to EIGRP Vector Metrics Values
VMI Metric
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EIGRP Metric
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Mapping
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current data rate
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Bandwidth
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Used directly and is converted to kilobits.
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relative link quality resources
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Reliability
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Calculated according to the following formula:
if resources < 30%
(255 * ((relative link quality + resources)/2) / 100
else
(255 * relative link quality) / 100
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max data rate
relative link quality
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Delay
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Calculated according to the following formula:
calc_delay(maximum_data_rate) * 100 / relative link quality) / USEC_TO_MSEC.
The value used for USEC_TO_MSEC is 1000.
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load
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Load
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Calculated according to the following formula:
((255 * load) / 100)
|
Note
If the current data rate = 0; then (current data rate / max data rate) is defined to be 1.
Note
calc_delay is a function which checks the value against well-known delay/bandwidth values. If it does not match a well-known value, the formula used is 10,000,000,000 / max_data_rate.
Dynamic Cost Metric for VMI Interfaces
The dynamic cost metric used for interfaces is computed based on the Layer 2 (L2) feedback to Layer 3 (L3). The dynamic cost is calculated using the following formula:
L2L3API
Where the metric calculations are
S1 = ipv6 ospf dynamic weight throughput
S2 = ipv6 ospf dynamic weight resources
S3 = ipv6 ospf dynamic weight latency
S4 = ipv6 ospf dynamic weight L2 factor
OC = standard cost of a non-VMI route
Throughput = (current-data-rate)/(maximum-data-rate)
Router-dynamic cost= OC + (S1) + (S2) + (S3) + (S4)
For a dynamic cost to have the same cost as a default cost, all parameters must equal zero.
Each Layer 2 feedback can contribute a cost in the range of 0 to 65535. To tune down this cost range, use the optional weight keyword in conjunction with the throughput, resources, latency, or L2-factor keyword. Each of these weights has a default value of 100% and can be configured in the range from 0 to 100. When 0 is configured for a specific weight, that weight does not contribute to the Open Shortest Path First (OSPF) cost.
Because cost components can change rapidly, you may need to dampen the amount of changes in order to reduce network-wide churn. Use the optional hysteresis keyword with the threshold threshold-value keyword and argument to set a cost change threshold. Any cost change below this threshold is ignored
EIGRP Metric Dampening for VMI Interfaces
Because metric components could be changing rapidly, the frequency of the changes can have an impact on the network. Frequent changes require that prefixes learned though the VMI interface be updated and sent to all adjacencies. This update can result in further updates and, in a worst-case scenario, cause network-wide churn. To prevent such effects, metrics can be dampened, or thresholds set, so that any change that does not exceed the dampening threshold is ignored.
Network changes that cause an immediate update include
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a down interface
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a down route
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any change in a metric which results in the router selecting a new nexthop
Dampening the metric changes can be configured based on change or time intervals.
If the dampening method is change-based, changes in routes learned though a specific interface, or in the metrics for a specific interface, will not be advertised to adjacencies until the computed metric changes from the last advertised value significantly enough to cause an update to be sent.
If this dampening method is interval-based, changes in routes learned though a specific interface, or in the metrics for a specific interface, will not be advertised to adjacencies until the specified interval is met, unless the change results in a new route path selection.
When the timer expires, any routes, which have outstanding changes to report, will be sent out. If a route changes, such that the final metric of the route matches the last updated metric, no update will be sent.
Neighbor Up/Down Signaling for OSFPv3 and EIGRP
MANETs are highly dynamic environments. Nodes may move into, or out of, radio range at a fast pace. Each time a node joins or leaves, of course, the network topology must be logically reconstructed by the routers. Routing protocols normally use timer-driven "hello" messages or neighbor timeouts to track topology changes, but for MANETs reliance on these mechanisms can result in unacceptably slow convergence.
This signaling capability provides faster network convergence by using link-status signals generated by the radio. The radio notifies the router each time a link to another neighbor is established or terminated by the creation and termination of PPPoE sessions. In the router, the routing protocols (OSPFv3 or EIGRP) respond immediately to these signals by expediting formation of a new adjacency (for a new neighbor) or tearing down an existing adjacency (if a neighbor is lost). For example, if a vehicle drives behind a building and loses its connection, the router will immediately sense the loss and establish a new route to the vehicle through neighbors that are not blocked. This high speed network convergence is essential for minimizing dropped voice calls and disruptions to video sessions.
When VMI with PPPoE is used and a partner node has left or a new one has joined, the radio informs the router immediately of the topology change. Upon receiving the signal, the router immediately declares the change and updates the routing tables.
The signaling capability reduces routing delays and prevents applications from timing out; enables network-based applications and information to be delivered reliably and quickly over directional radio links; provides faster convergence and optimal route selection so that delay-sensitive traffic such as voice and video are not disrupted; and reduces impact on radio equipment by minimizing the need for internal queuing/buffering; also provides consistent Quality of Service for networks with multiple radios.
The messaging allows for flexible rerouting when necessary because of
•
Noise on the Radio links
•
Fading of the Radio links
•
Congestion of the Radio links
•
Radio link power fade
•
Utilization of the Radio
Figure 3 illustrates the signaling sequence that occurs when radio links go up and down.
Figure 3 Up and Down Signaling Sequence
PPPoE Credit-based Flow Control
Each radio initiates a PPPoE session with its local router as soon as the radio establishes a link to another radio. Once the PPPoE sessions are active for each node, a PPP session is then established end-to-end (router-to-router). This process is duplicated each time a radio establishes a new link.
The carrying capacity of each radio link may vary due to location changes or environmental conditions, and many radio transmission systems have limited buffering capabilities. To minimize the need for packet queuing in the radio, Cisco has implemented extensions to the PPPoE protocol that enable the router to control traffic buffering in congestion situations. Implementing flow-control on these router-to-radio sessions also will allow use of quality of service features such as fair queuing.
The solution utilizes a credit-granting mechanism documented in an IETF informational draft. When the PPPoE session is established, the radio can request a flow-controlled session. If the router acknowledges the request, all subsequent traffic must be flow-controlled. If a flow control session has been requested and cannot be supported by the router, the session is terminated. Typically, both the radio and the router initially grant credits during session discovery. Once a device exhausts its credits, it must stop sending until additional credits have been granted. Credits can be added incrementally over the course of a session.
IPv6 Addresses
You can configure VMI interfaces with IPv6 addresses only, IPv4 addresses only, or both IPv4 and IPv6 addresses.
IPv6 addresses are assigned to individual router interfaces and enable the forwarding of IPv6 traffic globally on the router. By default, IPv6 addresses are not configured and IPv6 routing is disabled.
Note
The ipv6-address argument in the ipv6 address command must be in the form documented in RFC 2373 where the address is specified in hexadecimal using 16-bit values between colons.
The /prefix-length argument in the ipv6 address command is a decimal value that indicates how many of the high-order contiguous bits of the address comprise the prefix (the network portion of the address) A slash mark must precede the decimal value.
Restrictions for IPv6 Addressing
In Cisco IOS Release 12.2(4)T or later releases, Cisco IOS Release 12.0(21)ST, and Cisco IOS Release 12.0(22)S or later releases, the ipv6 address or ipv6 address eui-64 command can be used to configure multiple IPv6 global addresses within the same prefix on an interface. Multiple IPv6 link-local addresses on an interface are not supported.
Prior to Cisco IOS Releases 12.2(4)T, 12.0(21)ST, and 12.0(22)S, the Cisco IOS command-line interface (CLI) displays the following error message when multiple IPv6 addresses within the same prefix on an interface are configured as:
Prefix <prefix-number> already assigned to <interface-type>
For additional information about IPv6 addressing, refer Implementing IPv6 Addressing in the Cisco IOS IPv6 Configuration Guide.
Multicast Support for VMI Interfaces
VMI interfaces operate, by default, in aggregate mode, which means that all of the virtual-access interfaces created by PPPoE sessions are logically aggregated under the configured VMI. That is, applications above Layer 2, such as, EIGRP and OSPFv3, should be defined on the VMI interface only. Packets sent to the VMI interface will be correctly forwarded to the correct virtual-access interface(s).
If you are running multicast applications that require the virtual-access interfaces to be exposed to applications above Layer 2 directly, you can configure the VMI to operate in bypass mode. Most multicast applications require that the virtual-access interfaces be exposed directly to the routing protocols to insure that that multicast Reverse Path Forwarding (RPF) can operate as expected. When you use the bypass mode, you must define a VMI interface to handle presentation of cross-layer signals such as, neighbor up, neighbor down, and metrics. Applications will be aware of the actual underlying virtual-access interfaces, and will send packets to them directly. Additional information is required on the virtual template configuration. Operating the VMI in bypass mode can cause databases in the applications to be larger than would normally be expected because knowledge of more interfaces is required for normal operation.
After configuring the bypass mode, Cisco recommends that you save the running configuration to NVRAM to override the default mode of operation for VMI to logically aggregate the virtual-access interfaces..
How to Configure Router-to-Radio Links Using VMI PPPoE
This section identifies the tasks that will be used to configure VMI PPPoE. Configuring the VMI PPPoE involves implementing the infrastructure, establishing the IPv4 and IPv6 addressing schemes, and configuring the routing environment. This document contains configuration guidelines only for configuration of PPPoE as it relates to VMIs. For details about configuring PPPoE, refer to the Cisco IOS Broadband and DSL Configuration Guide. For details about PPPoE commands, refer to the Cisco IOS Broadband and DSL Command Reference.
•
Creating a Subscriber Profile for PPPoE Service Selection (Required)
•
Configuring the PPPoE Profile for PPPoE Service Selection (Required)
•
Configuring PPPoE on an Ethernet Interface (Required)
•
Creating and Configuring a Virtual Template for VMI PPPoE (Optional)
•
Creating and Configuring a VMI Interface for EIGRP IPv4 (Optional)
•
Creating and Configuring a VMI interface for EIGRP IPv6 (Optional)
•
Creating and Configuring a VMI Interface for OSPFv3(Optional)
•
Setting the EIGRP Change-based Dampening Interval for VMI Interfaces using classic-style configuration (Optional)
•
Setting the EIGRP Change-based Dampening Interval for VMI Interfaces using named-style configuration (Optional)
•
Setting the EIGRP Interval-based Dampening Interval for VMI Interfaces using classic-style configuration
•
Setting the EIGRP Interval-based Dampening Interval for VMI Interfaces using named-style configuration
•
Enabling Multicast Support on a VMI Interface (Optional)
•
Creating and Configuring a VMI Interface for OSPFv3 (Optional)
•
Verifying the VMI Configuration (Optional)
Creating a Subscriber Profile for PPPoE Service Selection
Perform this task to configure a subscriber profile for PPPoE service selection.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
subscriber profile profile-name
4.
pppoe service manet_radio
5.
exit
6.
subscriber authorization enable
7.
exit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
subscriber profile profile-name
Example:
Router(config)# subscriber profile manet
|
Enters Subscriber Profile configuration mode.
|
Step 4
|
pppoe service manet_radio
Example:
Router(config-sss-profile)# pppoe service
manet_radio
|
Adds a PPPoE MANET radio service name to a subscriber profile to enable the use of the VMI interface.
|
Step 5
|
exit
Example:
Router(config-sss-profile)# exit
|
Returns to the global configuration mode.
|
Step 6
|
subscriber authorization enable
Example:
Router(config)# subscriber authorization enable
|
Enable Subscriber Service Switch type authorization. This command is required when VPDN is not used.
|
Step 7
|
exit
Example:
Router(config)# exit
|
Returns to the previleged EXEC mode.
|
What to Do Next
After you have defined the PPPoE subscriber profile and service, you must apply the definitions to a BBA group.
Configuring the PPPoE Profile for PPPoE Service Selection
Perform this task to associate a subscriber profile with a PPPoE profile. In this configuration, the BBA group name should match the subscriber profile name previously defined in the subscriber profile. In this case, the profile name used as the service name is manet_radio.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
bba-group pppoe {group-name | global}
4.
virtual-template template-number
5.
service profile subscriber-profile-name [refresh minutes]
6.
end
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
bba-group pppoe {group-name | global}
Example:
Router(config)# bba-group pppoe group1
|
Defines a PPPoE profile and enters BBA group configuration mode.
• The global keyword creates a profile that will serve as the default profile for any PPPoE port that is not assigned a specific profile.
|
Step 4
|
virtual-template template-number
Example:
Router(config-bba-group)# virtual-template 1
|
Specifies which virtual template will be used to clone virtual access interfaces for all PPPoE ports that use this PPPoE profile.
|
Step 5
|
service profile subscriber-profile-name
[refresh minutes]
Example:
Router(config-bba-group)# service profile
subscriber-group1
|
Assigns a subscriber profile to a PPPoE profile.
• The PPPoE server will advertise the service names that are listed in the subscriber profile to each PPPoE client connection that uses the configured PPPoE profile.
• The PPPoE configuration that is derived from the subscriber gold_isp_A under the PPPoE profile. Use the service profile command with the refresh keyword and the minutes argument to cause the cached PPPoE configuration to be timed out after a specified number of minutes.
|
Step 6
|
end
Example:
Router(config-bba-group)# end
|
(Optional) Returns to privileged EXEC mode.
|
Troubleshooting Tips
Use the show pppoe session and debug pppoe commands to troubleshoot PPPoE sessions.
Configuring PPPoE on an Ethernet Interface
Perform this task to assign a PPPoE profile to an Ethernet interface.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
interface interface-name slot/port
4.
pppoe enable [group group-name]
5.
end
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
interface interface-name slot/port
Example:
Router(config)# interface ethernet 3/1
|
Specifies a Ethernet interface and enters interface configuration mode. Ethernet, Fast Ethernet, and Gigabit Ethernet can be used.
|
Step 4
|
pppoe enable [group group-name]
Example:
Router(config-if)# pppoe enable group bba1
|
Enables PPPoE sessions on an Ethernet interface or subinterface.
Note If a PPPoE profile is not assigned to the interface by using the group group-name option, the interface will use the global PPPoE profile.
|
Step 5
|
end
Example:
Router(config-if)# end
|
(Optional) Exits the configuration mode and returns to privileged EXEC mode.
|
Creating and Configuring a Virtual Template for VMI PPPoE
To create and configure a virtual template, use the following commands beginning in global configuration mode. Cisco recommends that, when using the virtual template, you turn off the PPP keepalive messages to make CPU usage more efficient and to help avoid the potential for the router to terminate the connection if PPP keepalive packets are missed over a lossy Radio Frequency (RF) link.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
interface virtual-template number
4.
Perform step 5, if you are using IPv4. Perform steps 7 and 8, if you are using IPv6. If you are using both, perform steps 5, 6, and 7.
5.
ip unnumbered interface-type interface-number
6.
ipv6 enable
7.
ipv6 unnumbered interface-type interface-number
8.
end
DETAILED STEPS
| |
Command
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
interface virtual-template number
Example:
Router(config)# interface virtual-template 1
|
Creates a virtual template, and enters interface configuration mode.
|
Step 4
|
Perform step 5, if you are using IPv4. Perform steps 7 and 8, if you are using IPv6. If you are using both, perform steps 5, 6, and 7.
|
—
|
Step 5
|
ip unnumbered interface-type interface-number
Example:
Router(config-if)# ip unnumbered vmi 1
|
Enables IP processing of IPv4 on an interface without assigning an explicit IP address to the interface.
|
Step 6
|
ipv6 enable
Example:
Router(config-if)# ipv6 enable
|
If you are using IPv6, enter the ipv6 enable command to enable IPv6 processing on the interface.
|
Step 7
|
ipv6 unnumbered interface-type interface-number
Example:
Router(config-if)# ipv6 unnumbered vmi i
|
Enables IPv6 processing on an interface without assigning an explicit IPv6 address to the interface.
|
Step 8
|
end
Example:
Router(config-if)# end
|
(Optional) Exits the configuration mode and returns to privileged EXEC mode.
|
Where To Go Next
Refer to the "Virtual Template Interface Service" chapter in the Cisco IOS Dial Solutions Configuration Guide for additional information about configuring the virtual templates.
Examples
You can configure multiple virtual template interfaces for your VMI PPPoE connections. The selection of which virtual template to use is predicated on the service name sent by the radio during PPPoE session establishment. As an example, consider the following configuration:
subscriber authorization enable
pppoe service manet_radio_over_x_band
pppoe service manet_radio_over_c_band
interface Virtual-Template1
interface Virtual-Template2
Using this configuration, any PPPoE request for a session (presentation of a PPPoE Active Discovery Initiate, or PADI packet) with the service name of "manet_radio_over_x_band" would use Virtual-Template1 as the interface to be cloned. Conversely, any PADI presented by the radio with the service name of "manet_radio_over_c_band" would use Virtual-Template2.
Note
All service names used for MANET implementations must begin with the string "manet_radio".
Creating and Configuring a VMI Interface for EIGRP IPv4
Perform this task to create the VMI interface and associate it with the Ethernet interface on which PPPoE is enabled. When you create a VMI interface, assign the IPv6 or IPv4 address to that VMI interface definition. Do not assign any addresses to the corresponding physical interface.
The radio alerts the router with PADT messages that the layer-2 radio frequency (RF) connection is no longer alive. Cisco recommends that you turn off the PPP keepalive messages to make CPU usage more efficient and to help avoid the potential for the router to terminate the connection if PPP keepalive packets are missed over a lossy RF link.
Note
This configuration includes Quality of Service (QoS) fair queueing and service policy applied to the VMI interface. Make certain that any fair queueing left over from any previous configurations is removed before applying the new policy map to the virtual template in the VMI configuration.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
ip routing
4.
no virtual-template subinterface
5.
policy-map policy-mapname
6.
class class-default
7.
fair-queue
8.
interface virtual-template number
9.
ip unnumbered interface-type interface-number
10.
service-policy output policy-mapname
11.
no keepalive
12.
interface interface-type interface-number
13.
ip address address mask
14.
no ip redirects
15.
no ip split-horizon eigrp autonomous-system-number
16.
physical-interface interface-type/slot
17.
exit
18.
router eigrp autonomous-system-number
19.
network network-number ip-mask
20.
redistribute connected
21.
end
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
ip routing
Example:
Router# ip routing
|
Enables IP routing on the router.o
|
Step 4
|
no virtual template subinterface
Example:
Router# no virtual template subinterface
|
Disables the virtual template on the subinterface.
|
Step 5
|
policy-map policy-map-name
Example:
Router(config-pmap)# policy map fair queue
|
Enters policy map configuration mode and creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.
|
Step 6
|
class class-default
Example:
Router(config-pmap)# class class-default
|
Specifies the name of the class whose policy you want to create or change or specifies the default class (commonly known as the class-default class) before you configure its policy.
|
Step 7
|
fair-queue
Example:
Router(config-pmap-c)# fair-queue
|
Enables weighted fair queueing (WFQ) on the interface
|
Step 8
|
interface virtual-template number
Example:
Router(config-pmap-c)# interface
virtual-template 1
|
Enters interface configuration mode and creates a virtual template interface that can be configured and applied dynamically in creating virtual access interfaces.
|
Step 9
|
ip unnumbered interface-type interface-number
Example:
Router(config-if)# ip unnumbered vmi 1
|
Enables IP processing of IPv4 on a serial interface without assigning an explicit IP address to the interface
|
Step 10
|
service-policy output policy-mapname
Example:
Router(config-if)# service-policy output
fair-queue
|
Attaches a policy map to an input interface or virtual circuit (VC) or an output interface or VC, to be used as the service policy for that interface or VC.
|
Step 11
|
no keepalive
Example:
Router(config-if)# no keepalive
|
Turns off PPP keepalive messages to the interface.
|
Step 12
|
interface interface-type interface-number
Example:
Router(config-if)# interface vmi 1
|
Specifies the number of the VMI interface.
|
Step 13
|
ip address address mask
Example:
Router(config-if)# ip address 209.165.200.225
255.255.255.224
|
Specifies the IP address of the VMI interface.
|
Step 14
|
no ip redirect
Example:
Router(config)# no ip redirect
|
Disables the sending of Internet Control Message Protocol (ICMP) redirect messages if the Cisco IOS software is forced to resend a packet through the same interface on which it was received.
|
Step 15
|
no ip split-horizon eigrp
autonomous-system-number
Example:
Router(config)# no ip split-horizon eigrp 101
|
Disables the split horizon mechanism for the specified session.
|
Step 16
|
physical-interface interface-type/slot
Example:
Router(config-if)# physical-interface
FastEthernet 0/1
|
Creates the physical subinterface to be associated with the VMI interfaces on the router.
|
Step 17
|
exit
Example:
Router(config-if)# exit
|
Exits the interface configuration mode and returns to the global configuration mode.
|
Step 18
|
router eigrp autonomous-system-number
Example:
Router(config)# router eigrp 100
|
Enables EIGRP routing on the router and identifies the autonomous system number.
|
Step 19
|
network network-number ip-mask
Example:
Router(config)# network 209.165.200.225
255.255.255.224
|
Identifies the EIGRP network.
|
Step 20
|
redistribute connected
Example:
Router(config)# redistribute connected
|
Redistributes routes from one routing domain into another routing domain.
|
Step 21
|
end
Example:
Router(config)# end
|
(Optional) Exits the configuration mode and returns to privileged EXEC mode.
|
Creating and Configuring a VMI interface for EIGRP IPv6
Perform this task to create the VMI interface and associate it with the Ethernet interface on which PPPoE is enabled.
Prerequisites
When you create a VMI interface, assign the IPv6 address to that VMI interface definition.
The radio alerts the router with PADT messages that the layer-2 radio frequency (RF) connection is no longer alive. If you turn off the PPP keepalive messages, it can make CPU usage more efficient and help to avoid the potential for the router to terminate the connection if PPP keepalive packets are missed over a lossy RF link.
Restrictions
Do not assign any addresses to the corresponding physical interface.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
ipv6 unicast-routing
4.
ipv6 cef
5.
policy-map policy-mapname
6.
class class-default
7.
fair-queue
8.
interface virtual-template number
9.
ipv6 enable
10.
no keepalive
11.
service-policy output policy-mapname
12.
interface interface-type interface-number
13.
ipv6 address address/prefix-length
14.
ipv6 enable
15.
ipv6 eigrp as-number
16.
no ipv6 redirects
17.
no ipv6 split-horizon eigrp as-number
18.
physical-interface interface-type/slot
19.
ipv6 router eigrp
20.
no shutdown
21.
redistribute connected
22.
end
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
ipv6 unicast-routing
Example:
Router# ipv6 unicast-routing
|
Enables IPv6 unicast routing.
|
Step 4
|
ipv6 cef
Example:
Router# ipv6 cef
|
Enables IPv6 CEF on the router.
|
Step 5
|
policy-map policy-map-name
Router(config-pmap)# policy-map fair-queue
|
Enters policy map configuration mode and creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.
|
Step 6
|
class class-default
Example:
Router(config-pmap)# class class-default
|
Specifies the name of the class whose policy you want to create or change or specifies the default class (commonly known as the class-default class) before you configure its policy.
|
Step 7
|
fair-queue
Example:
Router(config-pmap-c)# fair-queue
|
Enables weighted fair queueing (WFQ) on the interface
|
Step 8
|
interface virtual-template number
Example:
Router(config-if)# interface virtual-template 1
|
Enters interface configuration mode and creates a virtual template interface that can be configured and applied dynamically in creating virtual access interfaces.
|
Step 9
|
ipv6 enable
Example:
Router(config-if)# ipv6 enable
|
Enables IPv6 routing on the virtual template.
|
Step 10
|
no keepalive
Example:
Router(config-if)# no keepalive
|
Turns off PPP keepalive messages to the virtual template.
|
Step 11
|
service-policy output policy-name
Example:
Router(config-if)# service-policy output
fair-queue
|
Attaches a policy map to an input interface or virtual circuit (VC) or an output interface or VC, to be used as the service policy for that interface or VC.
|
Step 12
|
interface interface-type interface-number
Example:
Router(config)# interface vmi 1
|
Creates a VMI interface.
|
Step 13
|
ipv6 address address/prefix
Example:
Router(config-if)# ipv6 address 2001:0DB8::/32
|
Specifies the IPv6 address for the interface.
|
Step 14
|
ipv6 enable
Example:
Router(config-if)# ipv6 enable
|
Enables IPv6 routing on the interface.
|
Step 15
|
ipv6 eigrp as-number
Example:
Router(config-if)# ipv6 eigrp 1
|
Enables Enhanced Interior Gateway Routing Protocol (EIGRP) for IPv6 on a specified interface and specifies the Autonomous System (AS) number.
|
Step 16
|
no ipv6 redirect
Example:
Router(config-if)# no ipv6 redirect
|
Disables the sending of Internet Control Message Protocol (ICMP) IPv6 redirect messages if Cisco IOS software is forced to resend a packet through the same interface on which the packet was received
|
Step 17
|
no ipv6 split-horizon eigrp as_number
Example:
Router(config-if)# no ipv6 split-horizon eigrp
100
|
Disables the split horizon for EIGRP IPv6. Associates this command with a specific EIGRP AS.
|
Step 18
|
physical-interface interface-type/slot
Example:
Router(config-if)# physical-interface
FastEthernet 1/0
|
Creates the physical subinterface to be associated with the VMI interfaces on the router.
|
Step 19
|
ipv6 router eigrp as-number
Example:
Router(config-if)# ipv6 router eigrp 100
|
Places the router in router configuration mode, creates an Enhanced Interior Gateway Routing Protocol (EIGRP) routing process in IPv6, and allows you to enter additional commands to configure this process.
|
Step 20
|
no shutdown
Example:
Router(config-if)# no shutdown
|
Restarts a disabled interface or prevents the interface from being shut down.
|
Step 21
|
redistribute connected
Example:
Router(config-if)# redistribute connected
|
Allows the target protocol to redistribute routes learned by the source protocol and connected prefixes on those interfaces over which the source protocol is running. Redistributes IPv6 routes from one routing domain into another routing domain.
|
Step 22
|
end
Example:
Router(config-if)# end
|
(Optional) Exits the configuration mode and returns to privileged EXEC mode.
|
Setting the EIGRP Change-based Dampening Interval for VMI Interfaces using classic-style configuration
Perform the following tasks to set the change-based dampening interval for VMI interfaces using classic-style configuration:
Prerequisites
This configuration assumes that a virtual template and appropriate PPPoE configurations have already been completed. Refer to the Cisco IOS IP Mobility Configuration Guide for VMI configuration details.
This configuration sets the threshold to 50 percent tolerance routing updates involving VMI interfaces and peers.
Note
You may configure this feature with either an IPv4 or an IPv6 address, or you may use both. If you are using both IPv4 and IPv6, then complete the entire configuration.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
interface interface-type interface-number
4.
ip address address mask
5.
no ip redirects
6.
no ip split-horizon eigrp autonomous-system-number
7.
ip dampening-change eigrp autonomous-system-number percentage
8.
ipv6 address address
or
ipv6 enable
9.
ipv6 eigrp autonomous-system-number
10.
no ipv6 split-horizon eigrp autonomous-system-number
11.
ipv6 dampening-change eigrp autonomous-system-number percentage
12.
router eigrp autonomous-system-number
13.
network address
14.
ipv6 router eigrp autonomous-system-number
15.
end
DETAILED STEPS
| |
Command
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
interface interface-type interface-number
Example:
Router(config)# interface vmi 1
|
Enters interface configuration and creates a VMI interface.
|
Step 4
|
ip address address mask
Example:
Router(config-if)# ip address 209.165.200.225
255.255.255.224
|
Specifies the IP address of the VMI interface.
|
Step 5
|
no ip redirects
Example:
Router(config-if)# no ip redirects
|
Prevents the router from sending redirects.
|
Step 6
|
no ip split-horizon eigrp autonomous-system-number
Example:
Router(config-if)# no ip split-horizon eigrp 101
|
Disables the EIGRP split horizon.
|
Step 7
|
ip dampening-change eigrp autonomous-system-number
percentage
Example:
Router(config-if)# ip dampening-change eigrp 1 50
|
Sets a threshold percentage to minimize or dampen the effect of frequent routing changes for IPv4.
|
Step 8
|
ipv6 address address
or ipv6 enable
Example:
Router(config)# ipv6 address 2001:0DB8::/32
|
Specifies the IPv6 address.
|
Step 9
|
ipv6 eigrp autonomous-system-number
Example:
Router(config-if)# ipv6 eigrp 1
|
Enables EIGRP for IPv6 on the interface.
|
Step 10
|
no ipv6 split-horizon eigrp autonomous-system-number
Example:
Router(config-if)# no ipv6 split-horizon eigrp 1
|
Disables the sending of IPv6 redirects messages on an interface.
|
Step 11
|
ipv6 dampening-change eigrp autonomous-system-number
percentage
Example:
Router(config-if)#ipv6 dampening-change eigrp 1 30
|
Sets a threshold percentage to minimize or dampen the effect of frequent routing changes for IPv6.
|
Step 12
|
router eigrp autonomous-system-number
Example:
Router(config-if)# router eigrp 1
|
Configures the EIGRP address family process and enters router configuration mode.
|
Step 13
|
Example:
Router(config-router)# network 209.165.200.225
|
Configures the a network address.
|
Step 14
|
ipv6 router eigrp autonomous-system-number
Example:
Router(config-router)# ipv6 router eigrp 1
|
Configures EIGRP routing process in IPV6.
|
Step 15
|
Example:
Router(config-rtr)#end
|
(Optional) Exits the current configuration mode and returns to privileged EXEC mode.
|
Setting the EIGRP Change-based Dampening Interval for VMI Interfaces using named-style configuration
Perform the following tasks to set the change-based dampening interval for VMI interfaces using named-style configuration:
Prerequisites
This configuration assumes that a virtual template and appropriate PPPoE configurations have already been completed. Refer to the Cisco IOS IP Mobility Configuration Guide for VMI configuration details.
This configuration sets the threshold to 50 percent tolerance routing updates involving VMI interfaces and peers.
Note
You may configure this feature with either an IPv4 or an IPv6 address, or you may use both. If you are using both IPv4 and IPv6, then complete the entire configuration.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
interface interface-type interface-number
4.
ip address address mask
5.
no ip redirects
6.
ipv6 address address
or
ipv6 enable
7.
router eigrp virtual-instance-name
8.
address-family ipv4 autonomous-system autonomous-system-number
9.
network network-address
10.
af-interface interface-name interface-number
11.
dampening-change percentage
12.
exit
13.
exit
14.
address-family ipv6 autonomous-system autonomous-system-number
15.
af-interface interface-name interface-number
16.
dampening-change percentage
17.
end
DETAILED STEPS
| |
Command
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
interface interface-type interface-number
Example:
Router(config)# interface vmi 1
|
Enters interface configuration and creates a VMI interface.
|
Step 4
|
ip address address mask
Example:
Router(config-if)# ip address 209.165.200.225
255.255.255.224
|
Specifies the IP address of the VMI interface.
|
Step 5
|
no ip redirects
Example:
Router(config-if)# no ip redirects
|
Prevents the router from sending redirects.
|
Step 6
|
ipv6 address address
or ipv6 enable
Example:
Router(config)# ipv6 address 2001:0DB8::/32
|
Specifies the IPv6 address.
|
Step 7
|
router eigrp virtual-instance-name
Example:
Router(config-if)# router eigrp name
|
Enables EIGRP for IPv6 on the interface.
|
Step 8
|
address-family ipv4 autonomous-system
autonomous-system-number
Example:
Router(config-router)# address-family ipv4
autonomous-system 1
|
Enters address-family configuration mode to configure an EIGRP routing instance.
|
Step 9
|
network network-address
Example:
Router(config-router-af)# network 209.165.200.225
|
Configures the network address.
|
Step 10
|
af-interface interface-name interface-number
Example:
Router(config-router-af)# af-interface vmi 1
|
Enters address-family interface configuration mode.
|
Step 11
|
dampening-change percentage
Example:
Router(config-router-af-interface)# dampening-change
50
|
Sets a threshold percentage to minimize or dampen the effect of frequent routing changes through an interface in an EIGRP address family.
|
Step 12
|
Example:
Router(config-router-af-interface)# exit
|
Exits the address-family interface configuration mode.
|
Step 13
|
Example:
Router(config-router-af)# exit
|
Exits the address-family configuration mode and enters the router confiuration mode.
|
Step 14
|
address-family ipv6 autonomous-system
autonomous-system-number
Example:
Router(config-router)# address-family ipv6
autonomous-system 1
|
Enters address-family configuration mode to configure an EIGRP routing instance for IPv6.
|
Step 15
|
af-interface interface-name interface-number
Example:
Router(config-router-af)# af-interface vmi 1
|
Enters address-family interface configuration mode.
|
Step 16
|
dampening-change percentage
Example:
Router(config-router-af-interface)# dampening-change
50
|
Sets a threshold percentage to minimize or dampen the effect of frequent routing changes through an interface.
|
Step 17
|
Example:
Router(config-router-af-interface)# end
|
(Optional) Exits the current configuration mode and returns to privileged EXEC mode.
|
Setting the EIGRP Interval-based Dampening Interval for VMI Interfaces using classic-style configuration
Perform this task to set an interval-based dampening interval for VMI interfaces using classic-style configuration.
Prerequisites
This configuration assumes that a virtual template and appropriate PPPoE configurations have already been completed. Refer to the Cisco IOS IP Mobility Configuration Guide for VMI configuration details.
This configuration sets the interval to 30 seconds at which updates occur for topology changes that affect VMI interfaces and peers:
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
interface interface-type interface-number
4.
ip address address mask
5.
no ip redirects
6.
no ip split-horizon eigrp autonomous-system-number
7.
ip dampening-change eigrp autonomous-system-number percentage
8.
ipv6 address address
or
ipv6 enable
9.
ipv6 eigrp autonomous-system-number
10.
no ipv6 split-horizon eigrp autonomous-system-number
11.
ipv6 dampening-interval eigrp autonomous-system-number percentage
12.
router eigrp autonomous-system-number
13.
network address
14.
ipv6 router eigrp autonomous-system-number
15.
end
DETAILED STEPS
| |
Command
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
interface interface-type interface-number
Example:
Router(config)# interface vmi 1
|
Enters interface configuration and creates a VMI interface.
|
Step 4
|
ip address address mask
Example:
Router(config-if)# ip address 209.165.200.225
255.255.255.224
|
Specifies the IP address of the VMI interface.
|
Step 5
|
no ip redirects
Example:
Router(config-if)# no ip redirects
|
Prevents the router from sending redirects.
|
Step 6
|
no ip split-horizon eigrp autonomous-system-number
Example:
Router(config-if)# no ip split-horizon eigrp 101
|
Disables the EIGRP split horizon.
|
Step 7
|
ip dampening-interval eigrp autonomous-system-number
interval
Example:
Router(config-if)# ip dampening-change eigrp 1 30
|
Sets a threshold time interval to minimize or dampen the effect of frequent routing changes through an interface.
|
Step 8
|
ipv6 address address
or ipv6 enable
Example:
Router(config)# ipv6 address 2001:0DB8::/32
|
Specifies the IPv6 address.
|
Step 9
|
ipv6 eigrp autonomous-system-number
Example:
Router(config-if)# ipv6 eigrp 1
|
Enables EIGRP for IPv6 on the interface.
|
Step 10
|
no ipv6 split-horizon eigrp autonomous-system-number
Example:
Router(config-if)# no ipv6 split-horizon eigrp 1
|
Disables the sending of IPv6 redirects messages on an interface.
|
Step 11
|
ipv6 dampening-interval eigrp
autonomous-system-number interval
Example:
Router(config-if)# ipv6 dampening-interval eigrp 1 30
|
Sets a threshold time interval to minimize or dampen the effect of frequent routing changes through an interface.
|
Step 12
|
router eigrp autonomous-system-number
Example:
Router(config-if)# router eigrp 1
|
Configures the EIGRP address family process and enters router configuration mode.
|
Step 13
|
Example:
Router(config-router)# network 209.165.200.225
|
Configures the a network address.
|
Step 14
|
ipv6 router eigrp autonomous-system-number
Example:
Router(config-router)# ipv6 router eigrp 1
|
Configures EIGRP routing process in IPV6.
|
Step 15
|
Example:
Router(config-rtr)#end
|
(Optional) Exits the current configuration mode and returns to privileged EXEC mode.
|
Setting the EIGRP Interval-based Dampening Interval for VMI Interfaces using named-style configuration
Perform this task to set an interval-based dampening interval for VMI interfaces using named-style configuration.
Prerequisites
This configuration assumes that a virtual template and appropriate PPPoE configurations have already been completed. Refer to the Cisco IOS IP Mobility Configuration Guide for VMI configuration details.
This configuration sets the interval to 30 seconds at which updates occur for topology changes that affect VMI interfaces and peers:
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
interface interface-type interface-number
4.
ip address address mask
5.
no ip redirects
6.
ipv6 address address
or
ipv6 enable
7.
router eigrp virtual-instance-name
8.
address-family ipv4 autonomous-system autonomous-system-number
9.
network network-address
10.
af-interface interface-name interface-number
11.
dampening-interval interval
12.
exit
13.
exit
14.
address-family ipv6 autonomous-system autonomous-system-number
15.
af-interface interface-name interface-number
16.
dampening-interval interval
17.
end
DETAILED STEPS
| |
Command
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
interface interface-type interface-number
Example:
Router(config)# interface vmi 1
|
Enters interface configuration and creates a VMI interface.
|
Step 4
|
ip address address mask
Example:
Router(config-if)# ip address 209.165.200.225
255.255.255.224
|
Specifies the IP address of the VMI interface.
|
Step 5
|
no ip redirects
Example:
Router(config-if)# no ip redirects
|
Prevents the router from sending redirects.
|
Step 6
|
ipv6 address address
or ipv6 enable
Example:
Router(config)# ipv6 address 2001:0DB8::/32
|
Specifies the IPv6 address.
|
Step 7
|
router eigrp virtual-instance-name
Example:
Router(config-if)# router eigrp name
|
Enables EIGRP for IPv6 on the interface.
|
Step 8
|
address-family ipv4 autonomous-system
autonomous-system-number
Example:
Router(config-router)# address-family ipv4
autonomous-system 1
|
Enters address-family configuration mode to configure an EIGRP routing instance.
|
Step 9
|
network network-address
Example:
Router(config-router-af)# network 209.165.200.225
|
Configures the network address.
|
Step 10
|
af-interface interface-name interface-number
Example:
Router(config-router-af)# af-interface vmi 1
|
Enters address-family interface configuration mode.
|
Step 11
|
dampening-interval interval
Example:
Router(config-router-af-interface)# dampening-interval
30
|
Sets a threshold time interval to minimize or dampen the effect of frequent routing changes through an interface.
|
Step 12
|
Example:
Router(config-router-af-interface)# exit
|
Exits the address-family interface configuration mode.
|
Step 13
|
Example:
Router(config-router-af)# exit
|
Exits the address-family configuration mode and enters the router confiuration mode.
|
Step 14
|
address-family ipv6 autonomous-system
autonomous-system-number
Example:
Router(config-router)# address-family ipv6
autonomous-system 1
|
Enters address-family configuration mode to configure an EIGRP routing instance for IPv6.
|
Step 15
|
af-interface interface-name interface-number
Example:
Router(config-router-af)# af-interface vmi 1
|
Enters address-family interface configuration mode.
|
Step 16
|
dampening-interval interval
Example:
Router(config-router-af-interface)# dampening-interval
30
|
Sets a threshold time interval to minimize or dampen the effect of frequent routing changes through an interface.
|
Step 17
|
Example:
Router(config-router-af-interface)# end
|
(Optional) Exits the current configuration mode and returns to privileged EXEC mode.
|
Enabling Multicast Support on a VMI Interface
Perform this task to enable bypass mode on a VMI interface and override the default aggregation that occurs on VMI interfaces.
Prerequistes
This configuration assumes that you have already configured a virtual template and appropriate PPPoE sessions for the VMI interface.
Restrictions
Using bypass mode can cause databases in the applications to be larger because knowledge of more interfaces are required for normal operation.
After you enter the mode bypass command, Cisco recommends that you copy the running configuration to NVRAM because the default mode of operation for VMI is to logically aggregate the virtual-access interfaces.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
interface interface-type interface-number
4.
mode bypass
5.
exit
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
interface type number
Example:
Router(config-if)# interface vmi1
|
Enters interface configuration mode and reates a VMI interface.
|
Step 4
|
mode bypass
Example:
Router(config-if)# mode bypass
|
Overrides the default aggregation on the VMI interface and sets the mode to bypass to support multicast traffic on the interface.
|
Step 5
|
end
Example:
Router(config-if)# exit
|
Exits interface configuration.
|
Creating and Configuring a VMI Interface for OSPFv3
Perform this task to create the VMI interface and associate it with the Ethernet interface on which PPPoE is enabled. When you create a VMI interface, assign the IPv6 or IPv4 address to that VMI interface definition.
Restrictions
Do not assign any addresses to the corresponding physical interface.
SUMMARY STEPS
1.
enable
2.
configure terminal
3.
ipv6 unicast-routing
4.
ipv6 cef
5.
policy-map policy-map-name
6.
class class-default
7.
fair-queue
8.
interface virtual-template number
9.
ipv6 enable
10.
no keepalive
11.
service-policy output policy-name
12.
interface interface-type interface-number
13.
ipv6 enable
14.
ipv6 ospf process-id area area-id [instance instance-id]
15.
ipv6 ospf network point-to-multipoint
16.
ipv6 ospf cost dynamic hysteresis [threshold threshold-value]
17.
ipv6 ospf cost dynamic weight throughput percent
18.
ipv6 ospf cost dynamic weight resources percent
19.
ipv6 ospf cost dynamic weight latency percent
20.
ipv6 ospf cost dynamic weight L2-factor percent
21.
ipv6 ospf process-id area area-id [instance instance-id]
22.
physical-interface interface-type/slot
23.
ipv6 router ospf 1
24.
router-id ip-address
25.
redistribute connected metric-type 1
26.
timers spf spf-delay spf-hold
27.
end
DETAILED STEPS
| |
Command or Action
|
Purpose
|
Step 1
|
enable
Example:
Router> enable
|
Enables privileged EXEC mode.
• Enter your password if prompted.
|
Step 2
|
configure terminal
Example:
Router# configure terminal
|
Enters global configuration mode.
|
Step 3
|
ipv6 unicast-routing
Example:
Router(config)# ipv6 unicst-routing
|
Enables IPv6 unicast routing.
|
Step 4
|
ipv6 cef
Example:
Router(config)# ipv6 cef
|
Enables IPv6 CEF on the router.
|
Step 5
|
policy-map policy-map-name
Example:
Router(config-pmap)# policy-map fair-queue
|
Enters policy map configuration mode and creates or modifies a policy map that can be attached to one or more interfaces to specify a service policy.
|
Step 6
|
class class-default
Example:
Router(config-pmap)# class class-default
|
Specifies the name of the class whose policy you want to create or change or specifies the default class (commonly known as the class-default class) before you configure its policy.
|
Step 7
|
fair-queue
Example:
Router(config-pmap)# fair-queue
|
Enables weighted fair queueing (WFQ) on the interface
|
Step 8
|
interface virtual-template number
Example:
Router(config-if)# interface virtual-template 1
|
Enters interface configuration mode and creates a virtual template interface that can be configured and applied dynamically in creating virtual access interfaces.
|
Step 9
|
ipv6 enable
Example:
Router(config-if)# ipv6 enable
|
Enables IPv6 on the virtual template.
|
Step 10
|
no keepalive
Example:
Router(config-if)# no keepalive
|
Turns off PPP keepalive messages.
|
Step 11
|
service-policy output policy-name
Example:
Router(config-if)# service-policy output
fair-queue
|
Attaches a policy map to an input interface or virtual circuit (VC) or an output interface or VC, to be used as the service policy for that interface or VC.
|
Step 12
|
interface interface-type interface-number
Example:
Router(config-if)# interface vmi 1
|
Creates a VMI interface.
|
Step 13
|
ipv6 enable
Example:
Router(config-if)# ipv6 enable
|
Enables IPv6 routing on the VMI interface.
|
Step 14
|
ipv6 ospf process-id area area-id [instance
instance-id]
Example:
Router(config-if)# ipv6 ospf 1 area 0
|
Enables IPv6 OSPF routing on the interface.
|
Step 15
|
ipv6 ospf network point-to-multipoint
Example:
Router(config-if)# ipv6 ospf network
point-to-multipoint
|
Specifies the OSPF network type.
|
Step 16
|
ipv6 ospf cost hysteresis [threshold
threshold-value]
Example:
ipv6 ospf cost hysteresis threshold 1000
|
Sets the hysterisis tolerance for the interface.
|
Step 17
|
ipv6 ospf cost dynamic weight throughput
percent
Example:
Router(config-if)# ipv6 ospf cost dynamic
weight throughput 0
|
Sets the metric for the throughput threshold.
|
Step 18
|
ipv6 ospf cost dynamic weight resources percent
Example:
Router(config-if)# ipv6 ospf cost dynamic
weight resources 29
|
Sets the metric for the resource factor.
|
Step 19
|
ipv6 ospf cost dynamic weight latency percent
Example:
Router(config-if)# ipv6 ospf cost dynamic
weight latency 29
|
Sets the threshold for the latency factor.
|
Step 20
|
ipv6 ospf cost dynamic weight L2-factor percent
Example:
Router(config-if)# ipv6 ospf cost dynamic
weight L2-factor 29
|
Sets the metric for the Layer 2 -to- Layer 3 delay factor.
|
Step 21
|
ipv6 ospf process-id area area-id [instance
instance-id]
Example:
Router(config-if)# ipv6 ospf 1 area 0
|
Enables OSPF for IPv6 on an interface.
|
Step 22
|
physical-interface interface-type/slot
Example:
Router(config-if)# physical-interface
FastEthernet 0/1
|
Creates the physical subinterface to be associated with the VMI interfaces on the router.
|
Step 23
|
ipv6 router ospf process-id
Example:
Router(config-if)# ipv6 router ospf 1
|
Enables OSPF for IPv6 router configuration mode.
|
Step 24
|
router-id ip-address
Example:
Router(config-rtr)# router-id 10.1.1.1
|
Identifies a specific router rather than allowing the dynamic assignment of the router to occur.
|
Step 25
|
redistribute connected metric-type 1
Example:
Router(config-rtr)# redistribute connected
metric-type 1
|
Redistributes IPv6 routes from one routing domain into another routing domain. Allows the target protocol to redistribute routes learned by the source protocol and connected prefixes on those interfaces over which the source protocol is running.
|
Step 26
|
timers spf spf-delay spf-hold
Example:
Router(config-rtr)#timers spf 1 1
|
Specifies the spf delay time and maximum hold time in milliseconds to delay the calculations for Value ranges for these arguments is 1 to 600,000 milliseconds.
The OSPF Shortest Path First Throttling feature makes it possible to configure SPF scheduling in millisecond intervals and to potentially delay shortest path first (SPF) calculations during network instability. SPF is scheduled to calculate the Shortest Path Tree (SPT) when there is a change in topology
|
Step 27
|
end
Example:
Router(config-rtr)# end
|
(Optional) Exits the router configuration mode and returns to privileged EXEC mode.
|
Example
The following shows a sample output display to verify the OSPF Cost Dynamic for a VMI.
Router1# show ipv6 ospf interface serial2/0
Serial2/0 is up, line protocol is up
Link Local Address FE80::A8BB:CCFF:FE00:100, Interface ID 10
Area 1, Process ID 1, Instance ID 0, Router ID 200.1.1.1
Network Type POINT_TO_MULTIPOINT, Cost: 64 (dynamic), Cost Hysteresis: 200
Cost Weights: Throughput 100, Resources 20, Latency 80, L2-factor 100
Transmit Delay is 1 sec, State POINT_TO_MULTIPOINT,
Timer intervals configured, Hello 30, Dead 120, Wait 120, Retransmit 5
Index 1/2/3, flood queue length 0
Next 0x0(0)/0x0(0)/0x0(0)
Last flood scan length is 0, maximum is 0
Last flood scan time is 0 msec, maximum is 0 msec
Neighbor Count is 0, Adjacent neighbor count is 0
Suppress hello for 0 neighbor(s)
Verifying the VMI Configuration
Possible commands to use in verifying the configuration include:
•
show pppoe session all
•
show interface vmi
•
show vmi neighbors
•
show vmi neighbors detail
•
show ip eigrp interfaces
•
show ip eigrp neighbors
•
show ipv6 eigrp interfaces
•
show ipv6 eigrp neighbors
•
show ipv6 ospf interface
Configuration Examples for VMI PPPoE
•
Basic VMI PPPoE Configuration with EIGRP IPv4: Example
•
Basic VMI PPPoE Configuration Using EIGRP for IPv6: Example
•
VMI PPPoE Configuration Using EIGRP for IPv4 and IPv6: Example
•
EIGRP Metric Dampening for VMI Interfaces: Examples
•
VMI PPPoE Configuration for OSPFv3: Example
•
VMI PPPoE Configuration Using Multiple Virtual Templates: Example
•
Enabling Multicast Support on a VMI Interface: Examples
•
PPPoE Configuration: Example
•
Configuring Two VMIs: Example
•
Marking and Queuing Packets over VMI: Example
Basic VMI PPPoE Configuration with EIGRP IPv4: Example
This example illustrates the simplest configuration using EIGRP as the routing protocol. This configuration includes one VMI interface.
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
subscriber authorization enable
pppoe service manet_radio
pppoe service manet_radio
multilink bundle-name authenticated
no virtual-template subinterface
ip address 209.165.200.225 255.255.255.224
interface FastEthernet0/0
interface FastEthernet2/0
interface FastEthernet2/1
switchport access vlan 503
interface FastEthernet2/2
interface FastEthernet2/3
interface Virtual-Template1
ip address 209.165.200.226 255.255.255.224
ip address 209.165.200.226 255.255.255.224
ip address 209.165.200.226 255.255.255.224
no ip split-horizon eigrp 1
physical-interface FastEthernet0/0
network 209.165.200.226 255.255.255.224
network 209.165.200.227 255.255.255.224
Basic VMI PPPoE Configuration Using EIGRP for IPv6: Example
This example shows the basic requirements for configuring a VMI interface that uses EIGRP for IPv6 as the routing protocol. It includes one VMI interface.
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
subscriber authorization enable
pppoe service manet_radio
pppoe service manet_radio
multilink bundle-name authenticated
no virtual-template subinterface
ip address 209.165.200.226 255.255.255.224
ipv6 address 2001:0DB8::/32
interface FastEthernet0/0
interface FastEthernet2/0
interface FastEthernet2/1
switchport access vlan 503
interface FastEthernet2/2
interface FastEthernet2/3
interface Virtual-Template1
ip address 209.165.200.225 255.255.255.224
ip address 209.165.200.225 255.255.255.224
ipv6 address 2001:0DB8::/32
no ipv6 split-horizon eigrp 1
physical-interface FastEthernet0/0
VMI PPPoE Configuration Using EIGRP for IPv4 and IPv6: Example
The following examples shows how to configure VMI PPPoE using EIGRP as the IP routing protocol when you have both IPv4 and IPv6 addresses configured on the interface. This configuration includes one VMI interface.
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
subscriber authorization enable
pppoe service manet_radio
pppoe service manet_radio
multilink bundle-name authenticated
no virtual-template subinterface
ip address 209.165.200.225 255.255.255.224
ipv6 address 2001:0DB8::/32
interface FastEthernet0/0
interface FastEthernet2/0
interface FastEthernet2/1
switchport access vlan 503
interface FastEthernet2/2
interface FastEthernet2/3
interface Virtual-Template1
ip address 209.165.200.225 255.255.255.224
ip address 209.165.200.225 255.255.255.224
ipv6 address 2001:0DB8::/32
ip address 209.165.200.225 255.255.255.224
no ip split-horizon eigrp 1
ipv6 address 2001:0DB8::/32
no ipv6 split-horizon eigrp 1
physical-interface FastEthernet0/0
network 209.165.200.225 255.255.255.224
network 209.165.200.226 255.255.255.224
EIGRP Metric Dampening for VMI Interfaces: Examples
The dampening-change and dampening-interval commands are supported only for Mobile Ad Hoc Networking (MANET) router-to-radio links.
Dampening-change command
When a peer metric changes on an interface that is configured with the dampening-change command, EIGRP multiplies the dampening-change percentage with the old peer metric and compares the result (the threshold) to the difference between the old and new metrics. If the metric difference is greater than the calculated threshold, then the new metric is applied and routes learned from that peer are updated and advertised to other peers. If the metric difference is less than the threshold, the new metric is discarded.
There are exceptions that will result in an immediate update regardless of the dampening-change setting:
•
An interface is down.
•
A route is down.
•
A change in metric which results in the router selecting a new next hop.
Peer metric changes that do not exceed a configured change percentage and that do not result in a routing change do not result in an update being sent to other adjacencies. Peer metric changes are based on the stored last-update of the peer. Peer metric changes that exceed the threshold value are stored and used for future comparisons.
The dampening-interval command is supported only in Mobile Ad Hoc Networking (MANET) Router-to-Radio links.
Dampening-interval command
When a peer metric changes on an interface that is configured with a dampening interval, EIGRP will apply the metric change only if the time difference since the last metric changed exceeds the specified interval. If the time difference is less than the specified interval, the update is discarded.
There are exceptions that result in an immediate update regardless of the dampening interval settings:
•
An interface is down.
•
A route is down.
A change in metric that results in the router selecting a new next hop.
EIGRP Change-based Dampening for VMI Interfaces: Example
The following example configures EIGRP address-family Ethernet interface 0/0 to limit the metric change frequency to no more than one change in a 45-second interval:
Router(config)# router eigrp virtual-name
Router(config-router)# address-family ipv4 autonomous-system 5400
Router(config-router-af)# af-interface ethernet0/0
Router(config-router-af-interface)# dampening-interval 45
EIGRP Interval-based Dampening for VMI Interfaces: Example
The following example configures EIGRP address-family Ethernet interface 0/0 to limit the metric change frequency to no more than one change in a 45-second interval:
Router(config)# router eigrp virtual-name
Router(config-router)# address-family ipv4 autonomous-system 5400
Router(config-router-af)# af-interface ethernet0/0
VMI PPPoE Configuration for OSPFv3: Example
The following example shows how to configure VMI PPPoE using OSPFv3 as the routing protocol. This configuration includes three VMI interfaces.
subscriber authorization enable
pppoe service manet_radio
multilink bundle-name authenticated
no virtual-template subinterface
ip address 209.165.200.225 255.255.255.224
ipv6 address 2001:0DB8::/32
interface FastEthernet0/0
interface GigabitEthernet0/0
interface FastEthernet0/1
interface GigabitEthernet0/1
interface FastEthernet2/0
interface FastEthernet2/1
switchport access vlan 503
interface FastEthernet2/2
interface FastEthernet2/3
interface Virtual-Template1
interface Virtual-Template2
interface Virtual-Template3
ip address 209.165.200.225 255.255.255.224
ip address 10.2.2.2 255.255.255.0
ipv6 address 2001:0DB8::/32
ipv6 ospf network point-to-multipoint
ipv6 ospf cost dynamic hysteresis threshold 1000
ipv6 ospf cost dynamic weight throughput 0
ipv6 ospf cost dynamic weight resources 29
ipv6 ospf cost dynamic weight latency 29
ipv6 ospf cost dynamic weight L2-factor 29
physical-interface GigabitEthernet0/0
ipv6 ospf network point-to-multipoint
ipv6 ospf cost dynamic hysteresis threshold 1000
ipv6 ospf cost dynamic weight throughput 0
ipv6 ospf cost dynamic weight resources 29
ipv6 ospf cost dynamic weight latency 29
ipv6 ospf cost dynamic weight L2-factor 29
physical-interface GigabitEthernet0/1
ipv6 ospf network point-to-multipoint
ipv6 ospf cost dynamic hysteresis threshold 1000
ipv6 ospf cost dynamic weight throughput 0
ipv6 ospf cost dynamic weight resources 29
ipv6 ospf cost dynamic weight latency 29
ipv6 ospf cost dynamic weight L2-factor 29
physical-interface FastEthernet0/0
redistribute connected metric-type 1
VMI PPPoE Configuration Using Multiple Virtual Templates: Example
The following example shows how to configure VMI using multiple virtual templates. This example shows two VMIs, each with a different service name.
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
subscriber authorization enable
subscriber profile router1_ground
pppoe service manet_radio_ground
subscriber profile router1_satellite
pppoe service manet_radio_satellite
bba-group pppoe router1_ground
service profile router1_ground
bba-group pppoe router1_satellite
service profile router1_satellite
pppoe enable group router1_ground
pppoe enable group router1_satellite
interface Virtual-Template1
no peer default ip address
interface Virtual-Template2
no peer default ip address
description ground connection
ip address 209.165.200.225 255.255.255.224
physical-interface Ethernet0/0
description satellite connection
ip address 209.165.200.225 255.255.255.224
physical-interface Ethernet0/1
network 209.165.200.225 255.255.255.224
network 209.165.200.227 255.255.255.224
Enabling Multicast Support on a VMI Interface: Examples
Bypass Mode on VMI Interfaces
Enabling Multicast on VMI interfaces includes changing the VMI interface to bypass mode and enabling Protocol Independent Multicast (PIM) sparse mode on the virtual-template interface.
Router# configure terminal
Router(config)# interface Virtual-Template1
Router(config-if)#ip address 209.165.200.227 255.255.255.224
Router(config-if)# load-interval 30
Router(config-if)# no keepalive
Router(config-if)# ip pim sparse-dense-mode
Router(config-if)# service-policy output FQ
Router(config)# interface vmi1
Router(config-if)# ip address 10.3.9.1 255.255.255.0
Router(config-if)# load-interval 30
Router(config-if)# physical-interface FastEthernet0/0
Router(config-if)# mode bypass
OSPF v3 Using Bypass Mode for IPv6 Multicast Traffic Example
The ipv6 ospf network point-to-multipoint command in this OSPF example is needed to allow OSPFv3 to learn dynamic metrics from the link.
subscriber authorization enable
pppoe service manet_radio
multilink bundle-name authenticated
no virtual-template subinterface
ipv6 address 2001:0DB1::1/64
interface FastEthernet0/0
interface FastEthernet2/0
interface FastEthernet2/1
switchport access vlan 503
interface FastEthernet2/2
interface FastEthernet2/3
interface Virtual-Template1
ipv6 address 2001:0DB8::/32
ipv6 ospf network point-to-multipoint
ipv6 address 2001:0DB8::/32
ipv6 address 2001:0DB8::/32
physical-interface FastEthernet0/0
redistribute connected metric-type 1
EIGRP IPv4 with Bypass Mode Example
In this example, the IP address of the VMI1 interface needs to be defined, but it will not be routable because the vmi interface will be configured as down/down.
subscriber authorization enable
pppoe service manet_radio
multilink bundle-name authenticated
no virtual-template subinterface
ip address 209.165.200.225 255.255.255.224
interface FastEthernet0/0
interface FastEthernet2/0
interface FastEthernet2/1
switchport access vlan 503
interface FastEthernet2/2
interface FastEthernet2/3
interface Virtual-Template1
ip address 209.165.200.225 255.255.255.224
ip address 209.165.200.225 255.255.255.224
ip address 209.165.200.225 255.255.255.224
ipv6 address 2001:0DB8::/32
ip address 209.165.200.226 255.255.255.224
physical-interface FastEthernet0/0
network 209.165.200.225 255.255.255.224
network 209.165.200.226 255.255.255.224
EIGRP for IPv6 Example
subscriber authorization enable
pppoe service manet_radio
multilink bundle-name authenticated
no virtual-template subinterface
ipv6 address 2001:0DB8::/32
interface FastEthernet0/0
interface FastEthernet2/0
interface FastEthernet2/1
switchport access vlan 503
interface FastEthernet2/2
interface FastEthernet2/3
interface Virtual-Template1
ipv6 address 2001:0DB8::/32
ipv6 address 2001:0DB8::/32
ipv6 address 2001:0DB8::/32
physical-interface FastEthernet0/0
EIGRP with IPv4 and IPv6 Traffic Using Bypass Mode Example
subscriber authorization enable
pppoe service manet_radio
multilink bundle-name authenticated
no virtual-template subinterface
ip address 209.165.200.225 255.255.255.224
ipv6 address 2001:0DB8::/32
interface FastEthernet0/0
interface FastEthernet2/0
interface FastEthernet2/1
switchport access vlan 503
interface FastEthernet2/2
interface FastEthernet2/3
interface Virtual-Template1
ip address 209.165.200.225 255.255.255.224
ipv6 address 2001:0DB8::/32
ip address 209.165.200.226 255.255.255.224
ip address 209.165.200.226 255.255.255.224
ipv6 address 2001:0DB8::/32
ip address 209.165.200.226 255.255.255.224
physical-interface FastEthernet0/0
network 209.165.200.226 255.255.255.224
network 209.165.200.227 255.255.255.224
end
PPPoE Configuration: Example
In the following example, the subscriber profile uses a predefined string manet_radio to determine whether an inbound PPPoE session is coming from a device that supports VMI. All IP definitions are configured on the VMI interface rather than on the FastEthernet or Virtual-Template interfaces; when those interfaces are configured, do not specify either an IP address or an IPv6 address.
No IP address is specified and IPv6 is enabled by default on the VMI interface.
subscriber authorization enable
interface FastEthernet0/1
interface Virtual-Template 1
no peer default ip-address
physical-interface FastEthernet0/1
Configuring Two VMIs: Example
The following example shows a configuration that includes two VMIs, each having different service names.
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
subscriber authorization enable
subscriber profile router1_ground
pppoe service manet_radio_ground
subscriber profile router1_satellite
pppoe service manet_radio_satellite
bba-group pppoe router1_ground
service profile router1_ground
bba-group pppoe router1_satellite
service profile router1_satellite
pppoe enable group router1_ground
pppoe enable group router1_satellite
interface Virtual-Template1
no peer default ip address
interface Virtual-Template2
no peer default ip address
description ground connection
ip address 209.165.200.226 255.255.255.224
physical-interface Ethernet0/0
description satellite connection
ip address 209.165.200.227 255.255.255.224
physical-interface Ethernet0/1
network 209.165.200.226 255.255.255.224
network 209.165.200.227 255.255.255.224
Marking and Queuing Packets over VMI: Example
This configuration example includes QoS features in use with a VMI. Packets are marked either outbound or inbound over the VMI according to a policy map defined on the interface. This configuration differs slightly from standard QoS configurations because it requires that two different policies be applied to two different interfaces.
You apply the fair queue policy to the virtual template to define the queueing mechanism. To mark packets, you create a another policy and apply it to VMI to mark the traffic. The two policy maps work in tandem to provide the QoS support on the radio interface
Note
Packets will not be marked if you use the standard fair queue class or use hierarchical policy maps applied to the virtual templates.
The examples that follow show the device configurations that support the marking and queueing on a VMI.
Output Configuration of VMI and Policy Map Configured on Router 1
class-map match-all udp-traffic
interface Virtual-Template1
service-policy output my-marker
access-list 100 permit udp any any
Input Configuration for VMI and Policy Map configured on Router 2
class-map match-all udp-traffic
interface Virtual-Template1
service-policy input my-marker
access-list 100 permit udp any any
This display is output from the show policy-map command for the VMI and policy map configured on on Router 1.
Router1# show policy-map int vmi1
Service-policy output: my-marker
Class-map: udp-traffic (match-all)
5937331 packets, 6234197550 bytes
30 second offered rate 840000 bps, drop rate 0 bps
Class-map: class-default (match-any)
12829 packets, 769740 bytes
30 second offered rate 0 bps, drop rate 0 bps
This display is output from the show policy-map command for the VMI and policy map configured on on Router 2.
Router2# show policy-map int vmi1
Service-policy input: my-marker
Class-map: udp-traffic (match-all)
5971417 packets, 6150560540 bytes
30 second offered rate 824000 bps, drop rate 0 bps
Class-map: class-default (match-any)
26167 packets, 1623087 bytes
30 second offered rate 0 bps, drop rate 0 bps
Additional References
The following sections provide references related to Mobile Ad Hoc Networks for Router-to-Radio Communications.
Related Documents
Standards
Standard
|
Title
|
No new or modified standards are supported, and
support for existing standards has not been modified.
|
—
|
MIBs
MIB
|
MIB Link
|
No new or modified MIBs are supported by this feature, and support for existing MIBs has not been modified by this feature.
|
To locate and download MIBs for selected platforms, Cisco IOS releases, and feature sets, use Cisco MIB Locator found at the following URL:
http://www.cisco.com/go/mibs
|
RFCs
RFC
|
Title
|
RFC-2373
|
IP Version 6 Addressing Architecture
|
RFC-2516
|
A Method for Transmitting PPP Over Ethernet (PPPoE)
|
RFC-4938
|
PPP Over Ethernet (PPPoE) Extensions for Credit Flow and Link Metrics
|
Technical Assistance
Description
|
Link
|
The Cisco Support website provides extensive online resources, including documentation and tools for troubleshooting and resolving technical issues with Cisco products and technologies.
To receive security and technical information about your products, you can subscribe to various services, such as the Product Alert Tool (accessed from Field Notices), the Cisco Technical Services Newsletter, and Really Simple Syndication (RSS) Feeds.
Access to most tools on the Cisco Support website requires a Cisco.com user ID and password.
|
http://www.cisco.com/techsupport
|
Feature Information About the Mobile Ad Hoc Networks for Router-to-Radio Communications
Table 7 lists the features in this module and provides links to specific configuration information. Only features that were introduced or modified in Cisco IOS Release 12.3(14)T or a later release appear in the table.
Not all commands may be available in your Cisco IOS software release. For release information about a specific command, see the command reference documentation.
Use Cisco Feature Navigator to find information about platform support and software image support. Cisco Feature Navigator enables you to determine which Cisco IOS and Catalyst OS software images support a specific software release, feature set, or platform. To access Cisco Feature Navigator, go to http://www.cisco.com/go/cfn. An account on Cisco.com is not required.
Note
Table 7 lists only the Cisco IOS software release that introduced support for a given feature in a given Cisco IOS software release train. Unless noted otherwise, subsequent releases of that Cisco IOS software release train also support that feature.
Table 7 Feature Information for Mobile Ad Hoc Networks for Router-to-Radio Communications
Feature Name
|
Releases
|
Feature Information
|
PPPoE Support for Credit Flow and Metrics on Router-to-Radio Links Feature
|
12.4(15)XF
12.4(15)T
15.0(1)M
|
Credit-based flow control provides in-band and out-of-band credit grants in each direction. Link Quality Metrics are used to report link performance statistics that are then used to influence routing.
The following sections provide information about this feature:
• PPPoE Interfaces for Mobile Radio Communications
• PPPoE Credit-based Flow Control
• Configuration Examples for VMI PPPoE
The following commands were introduced or modified: show pppoe session, show vmi neighbors, show pppoe session
|
OSPFv3 Dynamic Interface Cost Support
|
12.4(15)XF
12.4(15)T
15.0(1)M
|
OSPFv3 Dynamic Interface Cost Support provides enhancements to the OSPFv3 cost metric for supporting Mobile Ad Hoc Networking.
The following section provides information about this feature;
• OSPF Cost Calculation for VMI Interfaces
The following commands were introduced or modified: ipv6 ospf cost, debug ipv6 ospf l2api, test ospfv3 interface name
|
EIGRP L2/L3 API and Tunable Metric for Mobile Ad Hoc Networks
|
12.4(15)XF
12.4(15)T
15.0(1)M
|
EIGRP uses dynamic raw radio link characteristics (current and maximum bandwidth, latency, and resources) to compute a composite EIGRP metric. A tunable Hysteresis mechanism helps to avoid churn in the network as a result of the change in the link characteristics.
In addition to the link characteristics, the L2L3 API provides an indication when a new adjacency is discovered, or an existing unreachable adjacency is again reachable. When EIGRP receives the adjacency signals, it responds with an immediate Hello out the specified interface to expedite the discovery of the EIGRP peer.
The following section provides information about this feature:
• Link Quality Metrics Reporting for OSPFv3 and EIGRP with VMI Interfaces
• Basic VMI PPPoE Configuration Using EIGRP for IPv6: Example
• VMI PPPoE Configuration Using EIGRP for IPv4 and IPv6: Example
The following commands were introduced or modified:
dampening-change, dampening-interval, debug eigrp notifications, debug vmi
|
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