Catalyst 6000
PSTN
Catalsyt 6000
with
Voice T1 and
FXS Modules
PBX
Cisco
CallManager
IP Phone
IP Phone
Analog
Phone
AVVID Gateway Selection • Chapter 3 85
It provides connectivity to legacy analog devices via a 24-port FXS module,
WS-X6624-FXS, which can be used for analog phones, faxes, speakerphones, and
modems.The analog FXS module acts as the gateway between the analog devices
and the IP network. By allowing for analog gateway functionality, organizations
can extend the useful life of their legacy analog devices. It also helps in the
migration to an IP telephony network by supporting existing fax machines and
conference speakerphones. Cisco does have an IP-based speakerphone, Cisco
7935, which was co-developed with Polycom.The analog to IP communication
is achieved via the voice CODECs of either G.711 or G.729a.
Digital PSTN and legacy PBX access is achieved with a Catalyst 6000 T1 or
E1 voice module, which is designed for larger enterprise campus environments.
The signaling supported for PSTN connections are Common channel signaling
(CCS) and ISDN PRI.The T1 module supports 23 channels in either signaling
mode, while the E1 module supports 29 channels for CCS and 30 for ISDN PRI
mode.The modules can also be configured to support transcoding and conference
bridging by configuring some ports for PBX or PSTN connectivity and
others for use as DSP resources.