- VISM Overview
- MPLS Overview
- RPM Overview
- VISM Voice Features
- Voice Connections
- Voice Over AAL2 Network
- VoIP Network
- Voice Over ATM Services on the VISM
- Digital Signal Processors
- VISM Clocking
- Commands for Adding, Configuring, and Displaying Voice Connections
- Commands for Verifying Voice Connections
- Introduction to Multiprotocol Label Switching
- The Problem of Persistent Loops Due to Protocol Conflicts
- Cisco WAN Switches with MPLS Support
- Setting Up MPLS on the MGX Switch
- MPLS and Virtual Private Networks Using the Route Processor Module
- RPM Memory Locations
- RPM Port Numbering
- Cisco IOS Command-Line Interface
- Commands for Configuring the RPM
- Commands for Setting Up the RPM ATM Switch Interface
- How to Set Up the RPM
- Configuring Subinterfaces
- PVCs on the RPM
- Commands for Configuring Subinterfaces
- Commands for Creating and Displaying PVCs on the RPM
- Creating Connections on the RPM
Digital Signal Processors
A major feature of VISM is the array of Digital Signal Processors (DSPs) that provide extensive voice signal processing capability.
Each VISM contains 37 DSPs. Twelve are general-purpose and can be configured to perform echo cancellation or data compression. Twenty-four can be used for data compression only. One DSP is a Jukebox DSP that is used to load code (program) overlays to the other 36 DSPs.
In addition to the DSPs, one HDLC controller is used for CCS signal processing.
Together, the DSPs support the DS0 channels of the eight T1/E1 lines.
A timeslot interchanger routes the DS0s to
A data compression DSP or
An echo cancellation DSP and then a data compression DSP or
The HDLC controller (for CCS processing)
DSPs are loaded with their programs at boot time.