Cisco PVDM4-128 Voice and Fax DSP Module for ISR 4000

What It Is

The Cisco PVDM4-128 is a high-density digital signal processor (DSP) module designed for voice and fax processing in Cisco Integrated Services Routers (ISRs). This 128-channel module belongs to the fourth-generation PVDM family, providing enhanced packet voice and fax capabilities for enterprise voice gateways. It enables concurrent voice codec support, conferencing, and transcoding services within supported router platforms.

Technical Details

• Channels: 128-channel packet voice/fax DSP capacity
• Module Type: PVDM4 (Packet Voice DSP Module, generation 4)
• Function: Voice and fax processing, including codec support and conferencing
• Form Factor: Module designed for dedicated PVDM slot on compatible Cisco ISR platforms
• Series Compatibility: Part of the Cisco PVDM module family for integrated services routers
• Technology: Digital signal processing for high-density voice traffic

Configuration & Options

• The module is ordered as a standalone unit (MPN: PVDM4-128)
• Compatible with Cisco ISR platforms that accept PVDM4 modules
• Supports mixed voice and fax channel configurations within the 128-channel capacity
• Can be combined with other PVDM modules in platforms with multiple slots, depending on router model
• Replacement part available as PVDM4-128= for spares or upgrades

Operating Conditions

The PVDM4-128 is intended for deployment inside enterprise or service-provider voice gateways, typically within Cisco 2900/3900 series or similar ISR chassis that support PVDM4 modules. It operates in controlled rack or cabinet environments with standard router power and cooling provisions. The module is suited for branch-office voice termination, PSTN gateway services, or IP telephony deployments requiring medium-to-high density DSP resources.