Cisco High-Density Analog Voice and Fax Network Module
Feature Overview
Feature Overview
The Cisco High-Density Analog Voice and Fax Network Module provides DTMF detection, voice compression and decompression, call progress tone generation, voice activity detection (VAD), echo cancellation, and adaptive jitter buffering for up to 16 ports.
The following port combinations are supported:
•Twelve Foreign Exchange Station (FXS) ports
•Eight Foreign Exchange Office (FXO) ports and four FXS ports
•Twelve FXS and four FXO ports
•Four Foreign Exchange Station (FXS) ports
The base card supports four FXS ports. The addition of an eight-port FXS expansion module can increase the capacity to twelve FXS ports. The addition of two four-port FXO expansion modules can increase the capacity to eight- FXO ports and four-FXS ports. The addition of one each of the FXS and FXO expansion modules can increase the capacity to twelve FXS ports and four- FXO ports. The FXO expansion module supports a power failure port which connects directly to the central office (CO) in case of failure.
The digital signal processors (DSPs) on the network module support up to eight-ports of high-complexity codecs or up to sixteen ports of medium-complexity and low-complexity codecs. The number of DSPs must be increased if more than eight ports of high-complexity codecs are needed. In this case, a DSP expansion module must be installed.
Table 1 shows analog voice port numbering, which differs for each of the voice-enabled routers. More current information may be available in the release notes that accompany the Cisco IOS software you are using.
Table 1 | High-Density Analog Voice Port Numbering |
| | | |
Base Module | | Telephony Signaling | Voice Port Numbers |
| | Interface | |
| | | |
NM-HDA-4FXS | | FXS | 0 to 3 |
| | | |
EM0 | | FXO | 4 to 7 |
| | | |
EM0 | | FXS | 4 to 11 |
| | | |
EM1 | | FXO | 14 to 17 |
| | | |
EM1 | | FXS | 14 to 21 |
| | | |
Caution No more than a total of 12 FXS ports can be configured at one time.
Cisco IOS Release 12.2(2)XT and 12.2(8)T
