Packet voice dsp modules – Cisco OL-12812-01 User Manual
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Connecting Cisco Voice Network Modules to the Network
60-Channel High-Density Voice Network Module
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Connecting Cisco Voice Network Modules to the Network
Figure 6
60-Channel High-Density Voice Network Module (NM-HDV)
The 60-channel HDV network module converts voice and fax into IP packets or frames that can be 
transmitted as VoIP over a variety of transport technologies (channelized T1/E1, Frame Relay, 
Asynchronous Transfer Mode (ATM), and others). The number of channels supported depends on the 
number of PVDMs installed:
•
Up to 6 channels per PVDM (30 channels for cards with 5 PVDMs) for high-complexity vocoders 
that support the following compression algorithms: G.711, G.726, G.729, G.723.1, G.728, and Fax 
Relay
•
Up to 12 channels per PVDM (60 channels for cards with 5 PVDMs) for medium-complexity 
vocoders that support the following compression algorithms: G.711, G.726, G.729a, and Fax Relay
Both a 60-channel HDV network module and a voice interface card (VIC) are required to connect to the 
public switched telephone network (PSTN) or a PBX. One VIC (providing one or two T1/E1 line 
interfaces) can be installed in the HDV network module. Currently, only the 1- and 2-port T1/E1 
multiflex trunk interface cards (VWIC-1MFT-T1, VWIC-2MFT-T1, and VWIC-2MFT-T1-DI) are 
supported using channel-associated signaling (CAS). In Cisco 3620 and Cisco 3640 routers, at least one 
other network module or WAN interface card (WIC) must be installed in the router to provide the 
connection to the IP LAN or WAN. In Cisco 3660 routers, a network module is required for WAN access 
or a direct connection is required for LAN access. In Cisco 2600 series routers, a WIC is required for 
WAN access or a direct connection is required for LAN access. 
Packet Voice DSP Modules
The HDV network module contains five 72-pin SIMM sockets or banks for packet voice DSP modules 
(PVDMs), numbered 0 through 4. (See 
.) Each socket can be filled with a single 72-pin PVDM.
The PVDMs must be installed starting from slot 0.
Note
PVDM and PVDM2 modules are not interchangeable. Use PVDM modules with the NM-HDV network 
module only, and use PVDM2 modules with the NM-HDV2 network module only.
NM-HDV
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