- Cisco WAN Modeling Tools User Guide

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Cisco WAN Modeling Tools Guide
OL-10426-01, Rev. A0
Chapter 1 Overview of the WAN Modeling Tools
Basic Usage/Charter Functionality
• IGX switch—A multi-service ATM networking switch that provides interfaces to support legacy and
emerging broadband applications. It supports ATM technology over subrate, narrowband E1 and T1,
and broadband E3 and T3 trunks. The IGX switch is used as the basis for a leased-line campus,
metropolitan area network (MAN) and WAN network, as an intelligent access device to high
speed-public digital services such as ATM, in a hybrid application using both, and as a WAN service
switch.
• Generic Node -- The NMT allows you to create your own node type for an ATM switch or feeder.
Use the node table to provide the high level specifications for the WAN product.
• Obsolete Equipment -- The NMT models obsolete equipment that users may encounter in CWM
extracts, and need to model for upgrade considerations. The following obsolete platforms are
modeled:
IPX switch, 3810 feeder, FastPad feeder, Port Concentrator Shelf Feeder
Basic Usage/Charter Functionality
The NMT models the WAN network using a classic node, link, and demand model. The nodes are the
sites in the site table, which are provisioned as Cisco MSSBU WAN switches. The links are the inter
switch trunks in the link table. The connections are specified in the voice, data, and bursty table.
The model provisions the network using the latest Cisco equipment, unless otherwise specified. The
model will verify that the network will route all connections, or will report on what resources have been
exceeded.
The NMT tool predicts the behavior of a WAN network that uses Cisco WAN switches (MGX, BPX and
IGX product series) as follows:
1. the user specifies the site locations and switch types, the links, and the connections in the network.
2. the NMT uses the AutoRoute and PNNI routing algorithms identical to those in the products.
3. based on the Connection Admission Control (CAC) parameters, the NMT verifies that the links and
connections can be provisioned, and that the connections can be routed.
4. the WAN network is modeled at the chassis, front card, and back card granularity level.
Note All connections used by the NMT are ATM connections, with the exception of some legacy IGX voice
and data services.
Keep the following in mind when you use the NMT:
• The NMT provides the primary reason any connections cannot be provisioned or routed, based on
the CAC rules.
• The NMT does not do discrete simulation, and no real time statistics are involved in the modeling.
• The NMT address the following real time issues only:
– delay estimate
– requirements specified in the CAC.
• The NMT verifies the connections routed in the base state
• The NMT verifies which connections will re-route under any network failure scenario.