The Cisco Fourth-Generation T1/E1 Multiflex Trunk Voice and WAN Network Interface Modules (NIMs) support data and voice applications on the Cisco 4451-X integrated services routers. These cards combine WAN-interface-card (WIC), voice-interface-card (VIC), ISDN Primary Rate Interface (PRI), dial-access integration, and channelized-data (CE1T1) functions to provide unparalleled flexibility, versatility, and investment protection through their many uses. Customers who choose to integrate data and voice in multiple steps preserve their investment in a T1/E1 WAN interface.The T1/E1 modules contain an onboard Cisco Packet Voice Digital Signal Processor Module 4 (PVDM4) slot, which requires a fourth-generation PVDM4 module. A PVDM4 on the T1/E1 module is necessary for the voice features. The PVDM4 also provides for echo cancellation of up to 128-ms echo-tail length for demanding network conditions.
Basic T1/E1 data
The multiflex trunk (MFT) versions act as WICs, supporting T1, fractional T1, E1, and fractional E1. To simplify remote management, these modules integrate a fully managed DSU/CSU for T1 deployments and a fully managed DSU for E1 deployments.
E1/G.703 data
In addition to the basic T1/E1 data support, the CE1T1 versions also support structured G.703 with G.704 framing and unstructured E1 (G.703) applications.
T1/E1 packet voice
All the modules support packet voice applications by providing T1, fractional T1, E1, and fractional E1 connections to private branch exchanges (PBXs) and central offices, thereby enabling the services and reducing voice and fax toll charges. An additional onboard PVDM4 is required. Also, each NIM has its own PVDM4, so each module can be connected to a different service provider with no single clock domain restriction.
Mixed data and packet voice
The modules can simultaneously support both data and voice, reducing the complexity and number of network components and facilitating a graceful migration to bandwidth-efficient packet voice.
Mixed data and packet voice with drop and insert
You can deploy all the modules as T1/E1 drop-and-insert multiplexers with integrated DSUs/CSUs, reducing the complexity of the network and the cost of the central-office ports by efficiently combining time-division multiplexing (TDM) voice (PBX), IP voice, and data on the same trunks.
