Table Of Contents

Introduction

Introduction

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This chapter provides a brief general overview of the Voice Switch Service Module (VXSM),
Release 5.2 and the organization of this document.

VXSM is a front card/back card set designed to operate in either a Cisco MGX 8880 or a Cisco MGX 8850 /PXM-45 chassis. There are three such card sets, one supports 4 OC3 ports, one supports 6 DS3 ports, and the other 48 T1 or E1 ports.

A Cisco MGX 8880 or Cisco MGX 8850 equipped with one or more VXSM card sets can function as a Media (Voice) Gateway in which voice traffic carried on conventional time-division multiplexed (TDM) voice circuits, including modem and fax data, is transported over IP or Asynchronous Transfer Mode (ATM) packet-switched networks.

Figure 1-1 MGX 8880 or MGX 8850 and VXSM as a Media Gateway

VXSM can route voice calls in two ways, namely:

•Voice over IP (VoIP) switching

•Trunking non-switching.

In VoIP switching applications, VXSM operates in conjunction with the PXM-45c card and AXSM or RPM-XF cards. The RPM-XF card is used when the packet network side supports IP traffic (for example, an Ethernet network). The AXSM card is used when the packet network employs ATM to carry IP traffic. In these applications voice traffic is switched between lines and trunks on the TDM and packet networks. The switching function is under the control of an external media gateway controller (often referred to as a call agent or softswitch). VoIP transmission of voice over a wide area packet network is often accomplished using an MPLS based network for routing the IP voice packets.

In trunking non-switching applications, VXSM operates in conjunction with PXM-45c and AXSM cards. Voice traffic is routed onto pre-provisioned ATM trunks according to pre-configured parameters. A media gateway controller is not used in this application.

Using up-to-date semiconductor technology and a bank of digital signal processors, each VXSM card can support the following example capacities.

A four OC3 card set can support up to 8064 DS0s with 50 calls per second and an average call hold time of 161 seconds.

A 48 T1 card set can support up to 1152 DS0s with 13 calls per second and an average call hold time of 90 seconds.

A 48 E1 card set can support up to 1488 DS0s with 17 calls per second and an average call hold time of 90 seconds.

The Cisco MGX 8880 and Cisco MGX 8850 chassis provides 12 card slots that are shared between any installed VXSM, AXSM, and PRM cards.

Applications for a VXSM equipped Cisco MGX 8880 or MGX 8850 include:

•Wireless or Wireline Tandem switch replacement or offload.

•ATM trunks between distributed Mobile Switching Centers (MSCs) in wireless networks.

•Wireless and wireline aggregation over ATM trunks.

This guide provides a general description of the features and functions of VXSM and describes how VXSM can be configured for switching and non-switching applications. The extensive set of VXSM commands is explained in detail.

Chapter 2, General Description, provides an overall description of the features and functions of the VXSM card sets.

Chapters 3 and 4, Configuring VoIP Applications and Configuring Trunking Applications, provide the basic configuration steps to get the application up and running.

Chapter 5, Configuring VXSM Features, describes other VXSM features such as configuring alarms, announcements, and so on.

Chapter 6, Upgrading from an Earlier Release, provides details for users who are upgrading from an existing earlier release of VXSM.

Chapter 7, Troubleshooting, provides basic troubleshooting tips.

Appendix A, Media Gateway Clocking, provides configuring and other information about successful network clocking.

This document should be used in conjunction with the Cisco Voice Switch Services (VXSM) Command Reference for MGX Switches and Media Gateways, Release 5.2. This command reference provides a complete description of all the VXSM command line commands in alphabetical order.

In addition to the VXSM card, the configuration sections of this guide cover other components such as PXM-45c, AXSM, and RPM-XF cards.in some detail. For a more complete description of these components, how to configure them, and how to use their commands, please refer to the following documents.

•Cisco MGX 8850 Multiservice Switch Overview, Release 1.1.3

•Cisco MGX 8850 (PXM45/PXM1E), Cisco MGX 8950, and Cisco MGX 8830 Command Reference, Release 5.2

•Cisco MGX Route Processor Module (RPM-XF) Installation and Configuration Guide, Release 4

In addition to the command line interface, many management and configuration tasks can be achieved using the Cisco Media Gateway Manager (MGM) and Cisco WAN Manager (CWM), for details please refer to Cisco Wide Area Network Manager User's Guide, Release 15. and the User Guide for Media Gateway Manager, Release 5.