Cisco PVDM4-256 Voice DSP Module for Enhanced Call Processing

What It Is

The Cisco PVDM4-256 is a high-density digital signal processor (DSP) module designed for voice and fax processing in enterprise voice gateways. It provides 256 channels of packet voice/fax support, making it suitable for medium-to-large unified communications deployments. This module is part of the Cisco PVDM4 series, which offers enhanced processing capacity for voice services.

Technical Details

• Channel capacity: 256 channels for packet voice/fax DSP operations
• Module type: PVDM4 (Packet Voice/Fax DSP Module, 4th generation)
• Form factor: Pluggable DSP module for compatible Cisco ISR platforms
• Voice processing: Supports voice and fax DSP functions
• Compatibility: Designed for Cisco integrated services routers that accept PVDM4 modules
• Model number: PVDM4-256 (spare part ordering code)

Configuration & Options

• Module is supplied as a standalone PVDM4-256 unit
• Compatible with Cisco 2900 and 3900 series ISR platforms (when used with appropriate adapters)
• For older platforms, PVDM2 series modules (e.g., PVDM2-8, PVDM2-16) are available as separate options
• PVDM2 adapter (PVDM2-ADPTR=) can be ordered separately for legacy slot compatibility
• Digital modem modules (PVDM2-12DM=) are offered as alternative DSP configurations

Operating Conditions

The module is deployed inside Cisco integrated services routers in enterprise branch offices or central sites requiring voice gateway functionality. It operates in temperature-controlled indoor environments within standard router chassis specifications. The PVDM4-256 is intended for continuous operation in voice-over-IP (VoIP) and fax-over-IP networks, supporting high-density call volumes.