Table Of Contents
PA-A2 ATM-CES Port Adapter Enhancements
Configuring an Available Bit Rate Permanent Virtual Circuit
Configuring Virtual Path Shaping
Available Bit Rate PVC Example
PA-A2 ATM-CES Port Adapter Enhancements
Description
The ATM-CES port adapters (PA-A2-4T1C-OC3SM, PA-A2-4T1C-T3ATM, PA-A2-4E1XC- OC3SM, PA-A2-4E1XC-E3ATM, PA-A2-4E1YC-OC3SM, and PA-A2-4E1YC-E3ATM) available on Cisco 7200 series routers now support the following new features:
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Available Bit Rate (ABR)—The ABR service category as specified in the ATM Forum Traffic Management Specification Version 4.0.
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In addition, all traffic shaping features available with the atm pvc interface command (peak average burst) are supported, and you can now configure the number of transmit channels for the interface with the atm max-channels interface configuration command.
The ATM-CES has four T1 (1.544 Mbps) or four E1 (2.048 Mbps) ports (75- or 120-ohm) that can support both structured (N x 64 kbps) and unstructured ATM Forum-compliant circuit emulation services (CES), and one port that supports an OC-3 (155 Mbps) single-mode intermediate reach interface or a T3 (45 Mbps) or E3 (34 Mbps) standards-based ATM interface. The target application of the ATM-CES port adapter is access to a broadband public or private ATM network where multiservice consolidation of voice, video, and data traffic over a single ATM link is a requirement.
Platforms
This feature is supported on the Cisco 7200 series routers.
Configuration Tasks
The following sections describe how to configure the new features or capabilities supported on the ATM-CES port adapter. The tasks described in these sections are optional:
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Configuring an Available Bit Rate Permanent Virtual Circuit
Available bit rate (ABR) is a quality of service class defined by the ATM Forum for ATM networks. ABR is used for connections that do not require timing relationships between source and destination. ABR provides no guarantees in terms of cell loss or delay, providing only best-effort service. Traffic sources adjust their transmission rate in response to information they receive describing the status of the network and its capability to successfully deliver data.
In ABR transmission, the peak cell rate (PCR) specifies the maximum value of the allowed cell rate (ACR), and minimum cell rate (MCR) specifies the minimum value for the ACR. ACR varies between the MCR and the PCR and is dynamically controlled using congestion control mechanisms.
Also, you can optionally configure the amount that the cell transmission rate increases or decreases in response to flow control information from the network or destination for available bit rate (ABR) VCs.
To create an Available Bit Rate (ABR) permanent virtual circuit (PVC), perform the following task beginning in interface configuration mode:
Note
To display information about the ABR PVC, use the show atm vc EXEC command.
For an ABR configuration example, see "Configuration Examples" later in this section.
Configuring Virtual Path Shaping
The ATM-CES port adapter supports multiplexing of one or more virtual circuits (VCs) over a virtual path (VP) that is shaped at a constant bandwidth. To use this feature, you configure a permanent virtual path (PVP) with a specific virtual path identifier (VPI). Any VCs that are created subsequently with the same VPI are multiplexed onto this VP; the traffic parameters of individual VCs are ignored.
The traffic shaping conforms to the peak rate that is specified when you create the VP. Any number of data VCs can be multiplexed onto a VP. However, the number of CES VCs that are multiplexed depends on the bandwidth requirement. Because of this requirement, the CES VCs cannot be oversubscribed.
Note
To create a PVP, perform the following task in interface configuration mode:
Step 1
atm pvp vpi [peak-rate]
Step 2
atm pvc vcd vpi vci aal-encap [peak average burst] [oam seconds]
Step 3
exit
Step 4
interface cbr slot/port
ces circuit circuit-number
ces pvc circuit-number interface atm slot/port vci number vpi number
The VPI value is the virtual path identifier to be associated with the PVP (valid values are in the range 0 to 255 inclusive). The peak rate argument is the maximum rate (in kbps) at which the PVP is allowed to transmit data. Valid values are in the range 84 kbps to line rate. The default peak rate is the line rate.
When you create a PVP, two VCs are created (VCI 3 and 4) by default. These VCs are created for VP end-to-end loopback and segment loopback OAM support.
The atm pvc command is rejected if a non-multiplexed VC with the specified VPI value already exists. This could happen if you first create a VC with a given VPI value and then you subsequently enter this command.
To display information about the PVP, use the show atm vp EXEC command.
Note
For an VP configuration example, see "Configuration Examples" later in this section.
Select Transmit Channels
You can select the number of transmit channels used by the interface. The atm max-channels command can be used to divide the available number (fixed) of transmit descriptors across the configured number of transmit channels.Typically, you think of a one-to-one association between a transmit channel and a VC; however the ATM-CES port adapter supports other types of VCs than data VCs (for example CES VCs). Also, the ATM-CES port adapter can multiplex one or more VCs over a single virtual path (VP) that is shaped, and the VP only requires a single transmit channel. Therefore, the term transmit channel is used rather then virtual circuit.
To set the number of transmit channels, perform the following task in interface configuration mode:
The maximum burst of packets that are allowed per VC is limited by the number of transmit descriptors allocated per VC. Because the total number of transmit descriptors available is limited by the available SRAM space, configuration of the number of transmit channels for the interface determines the number of transmit descriptors for each transmit channel. Hence the burst size for each transmit channel is determined by the atm max-channels command. For example, for 64 (default) numbers of transmit channels for the interface, 255 transmit descriptors are associated per transmit channel and for 512 numbers of transmit channels for the interface, 31 transmit descriptors are associated per transmit channel.
To display information on the transmit channels, use the show atm interface atm EXEC command.
Configuration Examples
The following examples show a typical configuration for an ABR PVC and a PVP.
Available Bit Rate PVC Example
The following example shows a typical ABR PVC configuration for the ATM-CES port adapter on a Cisco 7200 series router. In this example, the default peak cell rate and minimum cell rate is used (default PCR is the line rate and MCR is 0), and the ABR rate increase and decrease factor is set to 32.
router(config)# interface atm 4/0router(config-if)# ip address 1.1.1.1 255.255.255.0router(config-if)# atm pvc 13 1 13 aal5snap abrrouter(config-if)# atm abr rate-factor 32 32router(config-if)# map-group sanjose1router(config-if)# no shutdownrouter(config-if)# exitrouter(config)# exitVirtual Path Shaping Example
The following example shows a typical configuration for the ATM-CES port adapter with VP shaping on a Cisco 7200 series router. In this example, a VP is created with the VPI value of 1 and with a peak rate of 2000 kbps. The subsequent VCs created, one data VC and one CES VC, are multiplexed onto this VP.
router(config)# interface atm 6/0router(config-if)# ip address 2.2.2.2 255.255.255.0router(config-if)# atm pvp 1 2000router(config-if)# atm pvc 13 1 13 aal5snaprouter(config-if)# map-group sanjose2router(config-if)# no shutdownrouter(config-if)# exitrouter(config)# interface cbr 6/1router(config-if)# ces circuit 0router(config-if)# ces pvc 0 interface atm6/0 vpi 1 vci 100router(config-if)# exitrouter(config)# exitCommand Reference
This section documents new or modified commands. All other commands used with this feature are documented in the Cisco IOS Release 11.1 command references.
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atm abr rate-factor
To configure the amount that the cell transmission rate increases or decreases in response to flow control information from the network or destination for available bit rate (ABR) virtual circuits (VCs), use the atm abr rate-factor interface configuration command. To return to the default, use the no form of this command.
atm abr rate-factor [rate-increase-factor] [rate-decrease-factor]
no atm abr rate-factor [rate-increase-factor] [rate-decrease-factor]Syntax Description
Default
ABR rate increase and decrease factor is 16.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.1 CA.
To configure an ABR VC, use the atm pvc command with the abr keyword.
To verify the ABR rate factor, use the show atm interface atm EXEC command.
Examples
The following example sets the ABR rate factor to 32 for the next cell that is transferred on ATM interface 4/0:
interface atm 4/0atm abr rate-factor 32 32Related Commands
atm pvc
To create a permanent virtual circuit (PVC) and optionally to generate Operation, Administration, and Maintenance (OAM) F5 loopback cells, enable inverse ATM ARP, or configure Available Bit Rate (ABR) mode, use the atm pvc interface configuration command. To remove the specified PVC, use the no form of this command.
atm pvc vcd vpi vci aal-encap [peak average burst] | [abr [[pcr] [mcr]]]
[oam seconds] [inarp minutes]
no atm pvc vcd vpi vci aal-encap [peak average burst] | [abr [[pcr] [mcr]]]
[oam seconds] [inarp minutes]Syntax Description
Defaults
If peak and average rates are omitted, the PVC defaults to the line rate. Peak and average rates are then equal. By default, the virtual circuit is configured to run as fast as possible.
If the abr keyword is selected with no arguments, the default pcr value is the line rate, and the default mcr value is 0.
If the oam keyword is omitted, OAM cells are not generated. If the oam keyword is present but the seconds value is omitted, the default value of oam seconds is 10 seconds.
If the inarp keyword is missing, inverse ARPs are not generated. If the inarp keyword is present, but the timeout value is not given, then inverse ARPs are generated every 15 minutes.
Command Mode
Interface or subinterface configuration
Usage Guidelines
This command was modified in Cisco IOS Release 11.1 CA to support the ATM-CES port adapter and to add the abr keyword.
Available bit rate (ABR) is a quality of service class defined by the ATM Forum for ATM networks. ABR is used for connections that do not require timing relationships between source and destination. ABR provides no guarantees in terms of cell loss or delay, providing only best-effort service. Traffic sources adjust their transmission rate in response to information they receive describing the status of the network and its capability to successfully deliver data. In ABR transmission, the PCR specifies the maximum value of the allowed cell rate (ACR), and MCR specifies the minimum value for the ACR. ACR varies between the MCR and the PCR and is dynamically controlled using congesting control mechanisms. If you select the abr keyword peak, average, and burst arguments are not available. Also refer to the atm abr rate-factor interfaces command to configure the amount that the cell transmission rate increases or decreases in response to flow control information from the network or destination.
The order of command options is important. The inarp keyword can be specified either separately or after oam has been enabled. The peak, average, and burst arguments cannot be specified after either the inarp or the oam keywords.
The atm pvc command creates a PVC and attaches it to the specified VPI and VCI. Both vpi and vci cannot be specified as 0; if one is 0, the other cannot be 0. The aal-encap argument determines the AAL mode and the encapsulation method used.
Use one of the aal5mux encapsulation options to dedicate the specified virtual circuit to a single protocol; use the aal5snap encapsulation option to multiplex two or more protocols over the same virtual circuit. Whether you select aal5mux or aal5snap encapsulation might depend on practical considerations, such as the type of network and the pricing offered by the network. If the network's pricing depends on the number of virtual circuits set up, aal5snap might be the appropriate choice. If pricing depends on the number of bytes transmitted, aal5mux might be the appropriate choice because it has slightly less overhead.
If you are configuring an SVC, this command is required to configure the PVC that handles the SVC call setup and termination. In this case, specify qsaal for the aal-encap argument.
The router generates and echoes OAM F5 loopback cells, which verify connectivity. After OAM cell generation is enabled, a cell is transmitted periodically. The remote end must respond by echoing back the cells.
The router does not generate alarm indication signal (AIS) cells, which are used for alarm surveillance functions. However, if it receives an AIS cell, it responds by sending an OAM Far-end Remote Failure (FERF) cell.
Example
The following example configures the PVC as an ABR using the default the peak cell rate (the line rate) and the default minimum cell rate:
interface atm 2/0atm pvc 13 1 13 all5snap abrRelated Commands
atm pvp
To create a permanent virtual path (PVP) used to multiplex (or bundle) one or more VCs (especially CES and data VCs), use the atm pvp interface command. To remove a permanent virtual path, use the no form of this command.
atm pvp vpi [peak-rate]
no atm pvp vpiSyntax Description
Default
PVP is not configured.
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.1 CA.
The ATM-CES port adapter supports multiplexing of one or more VCs over a virtual path that is shaped at a constant bandwidth. For example, you can buy a virtual path service from an ATM service provider and multiplex both the CES and data traffic over the virtual path.
All subsequently created VCs with a vpi matching the vpi specified with the atm pvp command are multiplexed onto this PVP. This PVP connection is an ATM connection where switching is performed on the VPI field of the cell only. A PVP is created and left up indefinitely. All VCs that are multiplexed over a PVP share and are controlled by the traffic parameters associated with the PVP.
Changing the peak-rate causes the ATM-CES port adapter to go down and then back up.
When you create a PVP, two VC are created (VCI 3 and 4) by default. These VCs are created for VP end-to-end loopback and segment looback OAM support.
To verify the configuration of a PVP, use the show atm vp EXEC command.
Examples
The following example creates a permanent virtual path with a peak rate of 2000 kbps. The subsequent VC created are multiplexed onto this virtual path.
interface atm 6/0atm pvp 1 2000atm pvc 13 1 13 aal5snapexitinterface cbr 6/1ces circuit 0ces pvc 9 interface atm6/0 vpi 1 vci 100exitRelated Commands
atm tx-channels
The atm max-channels command replaces this command.
atm max-channels
To configure the number of transmit channels for the interface, use the atm max-channels interface configuration command. To return to the default, use the no form of this command.
atm max-channels number
no atm max-channelsSyntax Description
Default
64 channels
Command Mode
Interface configuration
Usage Guidelines
This command first appeared in Cisco IOS Release 11.1 CA.
Note
The atm max-channels command can be used to divide the available number (fixed) of transmit descriptors across the configured number of transmit channels.Typically, you think of a one-to-one association between a transmit channel and a VC; however, the ATM-CES port adapter supports other types of VCs than data VCs (for example CES VCs). Also, the ATM-CES port adapter can multiplex one or more VCs over a single virtual path (VP) that is shaped, and the VP only requires a single transmit channel. Therefore, the term transmit channel is used rather then virtual circuit.
The maximum burst of packets that are allowed per VC is limited by the number of transmit descriptors allocated per VC. Because the total number of transmit descriptors available is limited by the available SRAM space, configuration of the number of transmit channels for the interface determines the number of transmit descriptors for each transmit channel. Hence the burst size for each transmit channel is determined by the atm max-channels command. For example, for 64 (default) numbers of transmit channels for the interface, 255 transmit descriptors are associated per transmit channel and for 512 numbers of transmit channels for the interface, 31 transmit descriptors are associated per transmit channel.
To display information about the transmit descriptors, use the show atm interface atm EXEC command.
Examples
The following example sets the number of transmit descriptors for the interface to 120.
interface atm 2/0atm max-channels 120Related Commands
show atm interface atm
To display ATM-specific information about an ATM interface, use the show atm interface atm privileged EXEC command.
show atm interface atm slot/port
Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command was modified in Cisco IOS Release 11.1 CA to include sample output from the ATM-CES port adapter.
Sample Display
The following is sample output from the show atm interface atm command to display statistics on slot 6, port 0:
Router# show atm interface atm 6/0ATM interface ATM6/0:AAL enabled: AAL5, Maximum VCs: 2048, Current VCCs: 3Maximum Transmit Channels: 64Tx buffers 256, Rx buffers 256, Exception Queue: 32, Raw Queue: 32VP Filter: 0x7B, VCIs per VPI: 1024, Max. Datagram Size:4496PLIM Type:SONET - 155Mbps, TX clocking: INTERNAL0 input, 59 output, 0 IN fast, 0 OUT fastABR parameters, rif: 16 rdf: 16Config. is ACTIVEdescribes the fields shown in the display.
Related Commands
show atm vc
To display all active ATM virtual circuits (PVCs and SVCs) and traffic information, use the show atm vc privileged EXEC command.
show atm vc [vcd]
Syntax Description
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 10.0.
This command was modified in Cisco IOS Release 11.1 CA to include a sample display for the ATM-CES port adapter.
If no vcd value is specified, the command displays information for all PVCs and SVCs. The output is in summary form (one line per virtual circuit).
Sample Displays
The following is sample output from the show atm vc command when no vcd value is specified, displaying statistics for all PVCs for an ATM-CES port adapter on a Cisco 7200 series router. The status field is either ACTIVE or INACTIVE.
Router# show atm vcAAL / Peak Avg. BurstInterface VCD VPI VCI Type Encapsulation Kbps Kbps Cells StatusATM6/0 1 0 16 PVC AAL5-ILMI 155000 155000 94 ACTIVEATM6/0 2 0 5 PVC AAL5-SAAL 155000 155000 94 ACTIVEATM6/0.1 303 0 282 SVC LANE-LES 155000 155000 32 ACTIVEATM6/0.1 304 0 281 SVC LANE-LEC 155000 155000 32 ACTIVEATM6/0.1 307 0 286 MSVC LANE-LEC 155000 155000 32 ACTIVEATM6/0.1 308 0 285 MSVC LANE-LES 155000 155000 32 ACTIVEATM6/0.1 309 0 288 SVC LANE-BUS 155000 155000 32 ACTIVEATM6/0.1 310 0 287 SVC LANE-LEC 155000 155000 32 ACTIVEATM6/0.1 311 0 290 MSVC LANE-LEC 155000 155000 32 ACTIVEATM6/0.1 312 0 289 MSVC LANE-BUS 155000 155000 32 ACTIVEATM6/0.1 314 0 292 SVC LANE-LES 155000 155000 32 ACTIVEATM6/0.1 315 0 293 SVC LANE-BUS 155000 155000 32 ACTIVEThe following is sample output from the show atm vc command when a vcd value is specified, displaying statistics for that virtual circuit only.
Router# show atm vc 8ATM4/0: VCD: 8, VPI: 8, VCI: 8, etype:0x0, AAL5 - LLC/SNAP, Flags: 0x30PeakRate: 0, Average Rate: 0, Burst: 0 *32cells, VCmode: 0xE000InPkts: 181061, OutPkts: 570499, InBytes: 757314267, OutBytes: 2137187609InPRoc: 181011, OutPRoc: 10, Broadcasts: 570459InFast: 39, OutFast: 36, InAS: 11, OutAS: 6The following is sample output from the show atm vc command when a vcd value is specified for a CES circuit:
Router# show atm vc 2ATM6/0: VCD: 2, VPI: 10, VCI: 10, etype:0x0, CES - AAL1, Flags: 0x20138PeakRate: 2310, Average Rate: 2310, Burst Cells: 94, VCmode: 0x0OAM DISABLED, InARP DISABLEDReceived Cells: 0, Transmit Cells: 334272Status: ACTIVEThe following is sample output from the show atm vc command when generation of OAM F5 loopback cells has been enabled.
Router# show atm vc 7ATM4/0: VCD: 7, VPI: 7, VCI: 7, etype:0x0, AAL5 - LLC/SNAP, Flags: 0x30PeakRate: 0, Average Rate: 0, Burst: 0 *32cells, VCmode: 0xE000OAM frequency: 10, InARP DISABLEDInPkts: 0, OutPkts: 0, InBytes: 0, OutBytes: 0InPRoc: 0, OutPRoc:0, Broadcast:0InFast:0, OutFast:0, InAS:0, OutAS:0OAM F5 cells sent: 1, OAM cells received: 0The following is sample output from the show atm vc command for an incoming multipoint virtual circuit.
Router# show atm vc 3ATM2/0: VCD: 3, VPI: 0, VCI: 33, etype:0x809B, AAL5 - MUX, Flags: 0x53PeakRate: 0, Average Rate: 0, Burst: 0, VCmode: 0xE000OAM DISABLED, InARP DISABLEDInPkts: 6646, OutPkts: 0, InBytes: 153078, OutBytes: 0InPRoc: 6646, OutPRoc: 0, Broadcasts: 0InFast: 0, OutFast: 0, InAS: 0, OutAS: 0interface = ATM2/0, call remotely initiated, call reference = 18082vcnum = 3, vpi = 0, vci = 33, state = Activeaal5mux vc, multipoint callRetry count: Current = 0, Max = 10timer currently inactive, timer value = neverRoot Atm Nsap address: DE.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12The following is sample output from the show atm vc command for an outgoing multipoint virtual circuit.
Router# show atm v 6ATM2/0: VCD: 6, VPI: 0, VCI: 35, etype:0x800, AAL5 - MUX, Flags: 0x53PeakRate: 0, Average Rate: 0, Burst: 0, VCmode: 0xE000OAM DISABLED, InARP DISABLEDInPkts: 0, OutPkts: 818, InBytes: 0, OutBytes: 37628InPRoc: 0, OutPRoc: 0, Broadcasts: 818InFast: 0, OutFast: 0, InAS: 0, OutAS: 0interface = ATM2/0, call locally initiated, call reference = 3vcnum = 6, vpi = 0, vci = 35, state = Activeaal5mux vc, multipoint callRetry count: Current = 0, Max = 10timer currently inactive, timer value = neverLeaf Atm Nsap address: DE.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12Leaf Atm Nsap address: CD.CDEF.01.234567.890A.BCDE.F012.3456.7890.1234.12describes the fields shown in the displays.
Related Command
show atm vp
To display the statistics for all virtual paths (VP) on an interface or for a specific VP, use the show atm vp privileged EXEC command.
show atm vp [vpi]
Syntax Description
vpi
(Optional) ATM network virtual path identifier (VPI) of the permanent virtual path. The range is 0 to 255. The VPI is an 8-bit field in the header of the ATM cell.
Command Mode
Privileged EXEC
Usage Guidelines
This command first appeared in Cisco IOS Release 11.1 CA.
Example
The following is sample output from the show atm vp command. This output shows the interface name, the status of the interface, the administrative status of the interface, the port type, and the number of channels in use on the interface. The status of the interface can be UP (in operation) or DOWN (not in operation).
Router# show atm vp 1ATM6/0 VPI: 1, PeakRate: 155000, CesRate: 1742, DataVCs: 1, CesVCs:1, Status: ACTIVEVCD VCI Type InPkts OutPkts AAL/Encap Status1 100 PVC n/a n/a CES-AAL1 ACTIVE13 13 PVC 0 0 AAL5-SNAP ACTIVE409 3 PVC 0 0 F4 OAM ACTIVE410 4 PVC 0 0 F4 OAM ACTIVETotalInPkts: 0, TotalOutPkts: 0, TotalInFast: 0, TotalOutFast: 0, TotalBroadcasts: 0describes the fields shown in the display.
Related Commands
What to Do Next
For more information on the ATM-CES port adapter, refer to the PA-A2 ATM-CES Port Adapter Installation and Configuration publication. Also refer to the "PA-A1 ATM-CES Port Adapter" section in this document.
Guest
