Analog Phone Connectivity; Fax And Modem Connectivity; Protocols Supported - Cisco 450 Hardware Installation Manual

Overview of Cisco VG450 Voice Gateway

Analog Phone Connectivity

Cisco 450 Voice Gateway are ideal for analog phone deployments ranging from centralized to sparsely
concentrated or distributed topologies. Cisco 4000 Series Integrated Services Routers offer many supplementary
analog calling features, depending on the call control and signaling type used. All supplementary analog
features are supported through the FXS and FXO service modules. The analog interface on Cisco 4000 Series
also supports Feature Access Codes (FACs) for invoking supplementary services.

Fax and Modem Connectivity

FXS ports on Cisco 450 Voice Gateway support fax machines and modems. When using fax machines, the
gateways support T.38 fax relay and fax pass-through. T.38 fax relay technologies allow transfer of faxes
across the network with high reliability using less bandwidth than a voice call. All modems can be connected
to the Cisco VG Series Gateways and are transferred over the network using modem pass-through.

Protocols Supported

The voice gateways support the following protocols:
• SCCP
• H.323v4
• MGCP
• SIP
• Real-Time Transport Protocol (RTP)
• Secure Real-Time Transport Protocol (SRTP)
• Trivial File Transfer Protocol (TFTP)
• HTTP server
• Simple Network Management Protocol (SNMP)
• Telnet
• Dynamic Host Configuration Protocol (DHCP)
• DNS
• Cisco Unified Communications Manager or Cisco Unified Communications Manager Express redundancy
• Call survivability: MGCP failover to an H.323 connection to the Survivable Remote Site Telephony
• T.38 fax relay and modem pass-through
• Codec support: G.711, G.729. G.729a will be used if the gateway does not support G729 annex b
• RADIUS and TACACS+ for Telnet and authorization
The following table lists the feature specifications for Cisco 450 Voice Gateway.
Table 1: Cisco SM-X Single-Wide Service Module Feature Specifications
Feature SM-X-8FXS/12FXO
Tip and Ring
Interface for each
FXS port
support using Hot Standby Router Protocol (HSRP)
(SRST) router
SM-X-16FXS/2FXO SM-X-24FXS/4FXO
Cisco 450 Voice Gateway Hardware Installation Guide
Analog Phone Connectivity
SM-X-72FXS
3