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This chapter provides information on provisioning and managing ATM service in a network containing at least one IGX node. If the network contains other types of nodes, such as a BPX, please refer to the appropriate product documentation for specific information on provisioning ATM service on those nodes.
For information about the BPX, see Chapter 1, "The BPX Switch: Functional Overview ," in the Cisco BPX 8600 Series Installation and Configuration guide.
The IGX supports the following ATM service features:
The IGX supports the following standard ATM traffic classes to meet ATM-standard Class of Service (CoS) requirements:
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Note Service class templates (SCTs) are primarily used with virtual circuits (VCs) and must be used when configuring the IGX to work with a VSI master in a Label Switch Controller (LSC). |
SCTs provide a way to map a set of standard connection protocol parameters to different hardware platforms. For example, SCTs for the BPX and the IGX are different, but the BPX and IGX can still deliver equivalent CoS for full QoS.
On the IGX, the NPM stores a set of SCTs. When a UXM or UXM-E is initially configured, the appropriate SCTs are downloaded to the card. Later, if you configure a new interface on the card, the appropriate SCTs for that new interface will also be downloaded to the card.
Each SCT contains the following information:
Each SCT has an associated Qbin mapping table, which manages bandwidth by temporarily storing cells and serving them to the interface based on bandwidth availability and CoS priority.
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Note The default SCT, Template 1, is automatically assigned to a virtual interface (VI) when you configure the interface. |
There are nine SCTs available for assignment to a VSI. For more information on SCTs, see Figure 8-1.
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Caution SCTs can be reassigned on an operational interface, triggering a resynchronization process between the UXM or UXM-E and the controllers. However, for a Cisco MPLS VSI controller, reassignment of an SCT on an operational interface will cause all connections on the card to be resynchronized with the controller, and can affect service. |
Qbins store cells and serve them to an interface based on bandwidth availability and CoS priority (see Figure 8-2. For example, if CBR and ABR cells must exit the switch from the same interface, but the interface is already transmitting CBR cells from another source, the newly-arrived CBR and ABR cells are held in the Qbin associated with that interface. As the interface becomes accessible, the Qbin passes CBR cells to the interface for transmission. After the CBR cells have been transmitted, the ABR cells are passed to the interface and transmitted to their destination.
Qbins are used with VIs, in situations where the VI is a VSI with a VSI master running on a separate controller (a label switch controller or LSC). For a VSI master to handle a VSI, each virtual circuit (VC, also known as virtual channel when used in FR networks) must receive a specific service class specified through a 32-bit service type identifier. The IGX supports identifiers for the following service types:
When a connection setup request is received from the VSI master in the LSC, the VSI slave uses the service type identifier to index into an SCT database with extended parameter settings for connections matching that service type identifier. The VSI slave then uses these extended parameter settings to complete connection setup and necessary configuration for connection maintenance and termination on the fly.
The VSI master normally sends the VSI slave a service type identifier (either ATM Forum or MPLS), QoS parameters (such as CLR or CDV) and bandwidth parameters (such as PCR or MCR).
A Qbin template defines a default configuration for the set of Qbins attached to an interface. When you assign an SCT to an interface, switch software copies the Qbin configuration from the Qbin template and applies the Qbin configuration to all the Qbins attached to the interface.
Qbin templates only apply to the Qbins available to VSI partitions, meaning that Qbin templates only apply to Qbins 10-15. Qbins 0-9 are reserved and configured by Automatic Routing Management (ARM).
Some parameters on the Qbins attached to the interface can be re-configured for each interface. These changes do not affect the Qbin templates, which are stored on the NPM, though they do affect the Qbins attached to the interface.
For a visual description of the interaction between SCTs and Qbin templates, see Figure 8-3
The ATM connections shown in Table 8-1 are supported on the IGX.
Table 8-1 ATM Connections Supported on the IGX
| Chassis | Connection Endpoint | Chassis | Connection Endpoint |
|---|---|---|---|
The UXM-E supports up to 8000 virtual circuit (VC) or virtual path (VP) connections with interfaces operating as either NNI or UNI. Connections can be ATM or gateway connections.
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Note The UXM-E supports up to a maximum of 4000 gateway connections. |
The UXM-E supports both standard ABR with or without virtual source/virtual destination (VS/VD), and ABR with ForeSight (ABRFST).
Gateway connections require the UXM-E to translate between FastPackets and ATM cells and provide ATM-to-Frame Relay service or network interworking (SIW or NIW).
For more information on Frame Relay service or service or network interworking, see Chapter 9, "Cisco IGX 8400 Series Frame Relay Service."
For more information on the connections supported on the UXM-E, see Table 8-2.
Table 8-2 ATM Endpoints and Connection Types
For more information on the UXM or UXM-E, see the "Universal Switching Module" section. For more information on card limits, see "General IGX 8410 Switch Specifications" in the Cisco IGX 8400 Series Installation Guide.
This section provides information on how to provision ATM service on an IGX node. Information in this section applies to the UXM, and the UXM-E card sets. For more information on these cards, see the "Universal Switching Module" section in "Cisco IGX 8400 Series Cards."
Before provisioning ATM service, you should perform basic configuration on the node, set up a trunk, and configure at least one ATM line onto the node.
When provisioning ATM service, you will complete the following tasks:
1. Plan your connections to optimize bandwidth (see the "Calculating and Managing Bandwidth" section).
2. Determine a traffic class (CoS) for the connection (see the "Setting Up an ATM Connection" section).
3. Activate and configure the port on the local node.
4. (Optional) Specify a local management interface (LMI, ELMI, or ILMI).
5. (Optional) Configure the CoS queues for each traffic class.
6. (For network topologies utilizing LSCs and LERs) Configure VIs and VSIs.
7. (For network topologies utilizing LSCs and LERs) Apply SCTs to VIs and VSIs.
8. (For network topologies utilizing LSCs and LERs) Re-configure Qbins as necessary.
9. Configure the connection on the line.
Total bandwidth for the port is specified by the line characteristics (see "Cisco IGX 8400 Series Cards" and "General IGX 8410 Switch Specifications" in the Cisco IGX 8400 Series Installation Guide). However, this total bandwidth can be used to support many different features, and can be multiplexed with other ports to provide larger throughputs (see the "IMA on the IGX" section).
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Tip When calculating and managing bandwidth in an ATM network, consider the bandwidth requirements for all features being implemented in the network to avoid oversubscription. |
Connection admission control (CAC) limits the total bandwidth of all connections configured on a port to the port capacity.
For more information on optimizing network traffic, see the "Planning Bandwidth Usage" section.
Before setting up an ATM connection, you must configure the node, trunks, and the line to be used for the ATM connection. For information on configuring the node, see "Cisco IGX 8400 Series Nodes". For information on configuring a trunk, see "Cisco IGX 8400 Series Trunks". For information on configuring the line, see "Cisco IGX 8400 Series Lines".
To set up an ATM connection, use the following procedure:
Step 2 Activate the ATM port with the switch software upport command.
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Tip The URM requires execution of the switch software addport command to activate the internal ATM port located between the embedded UXM-E and the embedded router. For more information on configuration procedures specific to the URM, see the "URM Configuration" section. |
Step 3 Configure the ATM port with the desired characteristics with the switch software cnfport command.
Step 4 Display the queue depth and queue thresholds for all four egress queues (CBR, NRT-VBR, RT-VBR, ABR) with the switch software dspportq command.
Step 5 (Optional) Configure the port queue parameters with the switch software cnfportq command.
Step 6 Log in to the node on the remote end of the connection with the switch software vt command.
Step 7 At the remote node, repeat Step 1 through 5.
Step 8 Display the available connection classes with the switch software dspcls command. If a suitable connection class is already configured, note down its number for use with the addcon command in
Step 9.
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TimeSaver Use connection classes as templates for configuring multiple ATM connections. If a suitable connection class is not configured, use the cnfcls command to modify the connection class most like the one you want to apply to your connection. |
Step 9 Configure the desired connection onto the port with the switch software addcon command.
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Tip For connections with both endpoints on UXM-Es or BXMs, switch software will prompt you to enable or disable trunk cell routing restrictions. By restricting a connection between UXM-Es to trunk cell routing, switch software prevents ATM cells from passing over a FastPacket trunk. |
Full command descriptions for the switch software commands listed in Table 8-3 can be accessed at one of the following links:
Table 8-3 Switch Software Commands Related to ATM Connections
For information about FR service on the IGX, refer to Chapter 9, "Cisco IGX 8400 Series Frame Relay Service"
For installation and basic configuration information, see the Cisco IGX 8400 Series Installation Guide, Chapter 1, "Cisco IGX 8400 Series Product Overview"
For more information on switch software commands, refer to the Cisco WAN Switching Command Reference, Chapter 1, "Command Line Fundamentals ."
Posted: Mon May 12 15:35:19 PDT 2003
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