PVDM4-256 – 256-Channel Voice DSP – Motherboard or T1/E1 NIM Slot
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PVDM4-256 Description
PVDM4-256 is a Cisco PVDM4 voice DSP module for Cisco 4000 Series Integrated Services Routers, used to add high-density DSP resources for branch voice deployments, IP media services, and T1/E1 gateway designs. Cisco documents this module as a 256-channel high-density PVDM4 that installs in the router motherboard slot or in a supported fourth-generation T1/E1 voice and WAN NIM, supports 256 low-complexity, 192 medium-complexity, and 128 high-complexity voice channels, and is listed for IOS XE 3.10, XE SD-WAN 17.3, and vManage 20.3, with motherboard placement reserved for IP-based media functions such as conferencing, media optimization, and transcoding rather than TDM voice services.
Quick Specs
|
Parameter |
Specification |
|---|---|
|
Product ID |
PVDM4-256 |
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Product type |
PVDM4 voice DSP module |
|
Cisco description |
256-channel high-density voice DSP module |
|
Slot type |
On-board motherboard or T1/E1 module slot |
|
Supported platform family |
Cisco 4000 Series ISRs except ISR 4461 for motherboard PVDM4 support |
|
Low-complexity channels |
256 |
|
Medium-complexity channels |
192 |
|
High-complexity channels |
128 |
|
TDM voice service path |
Supported when installed on a T1/E1 NIM |
|
Motherboard service path |
IP media services such as conferencing and transcoding |
|
Minimum software listing |
IOS XE 3.10 / XE SD-WAN 17.3 / vManage 20.3 |
|
Module power |
4.85W |
Application Scenarios
Select PVDM4-256 when the Cisco 4000 Series ISR bill of materials needs the highest listed PVDM4 motherboard or T1/E1 NIM density instead of the 32-, 64-, or 128-channel tiers.
Use this module for T1/E1 voice designs where Cisco’s documented path places PVDM4 DSP resources on the voice WAN NIM and the channel plan exceeds the PVDM4-128 tier.
Choose this SKU for conferencing, transcoding, and media optimization planning when the ISR design uses the motherboard PVDM4 position and does not require that motherboard slot to provide TDM voice services.
Product Comparison
|
Parameter |
PVDM4-256 | |||
|---|---|---|---|---|
|
Cisco description |
256-channel high-density voice DSP module |
128-channel high-density voice DSP module |
64-channel high-density voice DSP module |
NIM PVDM with 256-channel DSP |
|
Product type |
PVDM4 voice DSP module |
PVDM4 voice DSP module |
PVDM4 voice DSP module |
NIM-based voice DSP module |
|
Slot type |
On-board motherboard or T1/E1 module slot |
On-board motherboard or T1/E1 module slot |
On-board motherboard or T1/E1 module slot |
Network Interface Module slot |
|
Low-complexity channels |
256 |
128 |
64 |
256 |
|
Medium-complexity channels |
192 |
96 |
48 |
192 |
|
High-complexity channels |
128 |
64 |
32 |
128 |
|
TDM service support |
Supported when installed on a T1/E1 NIM |
Supported when installed on a T1/E1 NIM |
Supported when installed on a T1/E1 NIM |
Not supported for NIM-PVDM-X modules |
|
Minimum software listing |
IOS XE 3.10 / XE SD-WAN 17.3 / vManage 20.3 |
IOS XE 3.10 / XE SD-WAN 17.3 / vManage 20.3 |
IOS XE 3.10 / XE SD-WAN 17.3 / vManage 20.3 |
IOS XE 3.16.1 / XE SD-WAN 17.3 / vManage 20.3 |
|
Platform context |
Cisco 4000 Series ISR PVDM4 path except ISR 4461 motherboard slot |
Cisco 4000 Series ISR PVDM4 path except ISR 4461 motherboard slot |
Cisco 4000 Series ISR PVDM4 path except ISR 4461 motherboard slot |
Catalyst 8300 and ISR 4461 NIM-slot platforms |
- In a PVDM4-256 vs PVDM4-128 comparison, the difference is DSP density: PVDM4-256 lists twice the channel count for each codec-complexity tier.
- The PVDM4-256 vs PVDM4-64 comparison is a capacity decision inside the same PVDM4 slot family, with PVDM4-256 providing four times the listed channel counts.
- For PVDM4-256 vs NIM-PVDM-256, the channel tier matches, but the slot type, platform context, and TDM service boundary are different.
- Buyers deciding which model to choose should confirm the required channel tier first, then verify whether the design needs the PVDM4 motherboard or T1/E1 NIM route rather than the NIM-PVDM form factor.
Selection Guide
1. Size the DSP tier before the slot check
Choose PVDM4-256 only when the voice design calls for 256 low-complexity, 192 medium-complexity, or 128 high-complexity channels in the PVDM4 family.
2. Use the PVDM4 form factor intentionally
Specify this module when the router design supports an on-board motherboard PVDM4 position or a Cisco T1/E1 NIM that accepts PVDM4 DSP hardware.
3. Keep motherboard media services separate from TDM voice
Plan motherboard installation for IP media services such as conferencing and transcoding; place the DSP on the T1/E1 NIM path when TDM voice services are required.
4. Do not replace it with a NIM-PVDM line item
Select NIM-PVDM-256 only when the BOM requires a Network Interface Module slot DSP option for the Catalyst 8300 or ISR 4461 NIM-slot context.
Ordering Checklist
|
Review Area |
Required Confirmation |
Procurement Risk |
|---|---|---|
|
Exact SKU |
Confirm PVDM4-256 rather than PVDM4-128, PVDM4-64, or NIM-PVDM-256 |
Avoids ordering the wrong DSP density or module form factor |
|
Router family |
Verify the Cisco 4000 Series ISR target and remember that ISR 4461 has no motherboard PVDM4 slot |
Prevents assigning the module to an unsupported motherboard position |
|
Slot placement |
Confirm motherboard placement for IP media services or T1/E1 NIM placement for TDM voice services |
Prevents a TDM voice design from depending on the motherboard slot |
|
Codec capacity |
Match the voice design to 256 low-, 192 medium-, or 128 high-complexity channels |
Prevents under-sizing the DSP channel pool |
|
License path |
Confirm Unified Communications Technology Package or current Smart Licensing requirements for the voice application |
Avoids treating DSP hardware as the complete voice entitlement |
Specifications
| Parameter | Specification | Parameter | Specification |
|---|---|---|---|
| Product ID | PVDM4-256 | Product type | PVDM4 voice DSP module |
| Cisco description | 256-channel high-density voice DSP module | Slot type | On-board motherboard or T1/E1 module slot |
| Supported platform family | Cisco 4000 Series ISRs except ISR 4461 for motherboard PVDM4 support | Low-complexity channels | 256 |
| Medium-complexity channels | 192 | High-complexity channels | 128 |
| TDM voice service path | Supported when installed on a T1/E1 NIM | Motherboard service path | IP media services such as conferencing and transcoding |
| Minimum software listing | IOS XE 3.10 / XE SD-WAN 17.3 / vManage 20.3 | Voice application licensing | Minimum Unified Communications Technology Package noted for voice applications |
| DSP technology | Multicore DSP technology | Interface | Integrated Services Card slot on motherboard or T1/E1 NIM |
| Operating temperature | 32 to 122 degrees F (0 to 50 degrees C) | Voltage | 3.3V |
| Current | 1.47A | Power | 4.85W |
| Weight | 0.08 lb (36 g) | Dimensions | 0.67 x 2.50 x 2.62 in. (1.7 x 5.1 x 6.7 cm) |
Get More Information
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Questions & Answers
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What is PVDM4-256?
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Where can PVDM4-256 be installed?
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Which channel count separates PVDM4-256 from PVDM4-128?
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Does PVDM4-256 provide high-complexity DSP capacity?
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Which software baseline and power draw apply to PVDM4-256?
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