PA-MC-4T1 Cisco 4-Port Multichannel T1 Port Adapter, Integrated CSU/DSU

Four independent 100-ohm T1 connections on RJ-48C receptacles are what the PA-MC-4T1, a Cisco 4-port multichannel T1 port adapter, puts on a router, and all four can be used at once. It is a single-width adapter with integrated CSU and DSU functions and DS0 channel support. The ENABLED LED sits beside one status LED per port: green means a good signal is arriving, yellow means loopback, and off means no good signal.

It is supported in the Catalyst RSM/VIP2 in Catalyst 5000 family switches, the Catalyst 6000 family FlexWAN module, the Cisco 7120, 7140, 7200 series, 7201, uBR7223 and uBR7246 routers, the 7304 PCI Port Adapter Carrier Card, and a VIP in Cisco 7000 and 7500 series routers. The FlexWAN module does not support ISDN. The 7301 and 7401ASR routers take only the eight-port members of the family.

Each T1 link supports Cisco HDLC, Frame Relay, PPP and SMDS DXI encapsulation, and time slots are numbered 1 to 24. Bit error rate testing runs on one port at a time and only over a framed T1 signal. After a cable is connected, Cisco IOS needs about 30 seconds to report the line up. The adapter can be removed online in 7100, 7200, 7200 VXR, uBR7200, 7201 routers, but inside a VIP, RSM/VIP2, FlexWAN or 7304 carrier card the host card must come out first. Serial and T1 port adapters have a category page at Cisco interface cards.