PA-MC-2T3-EC Cisco 2-Port Multichannel T3 Port Adapter, 7200 and 7301

The PA-MC-2T3-EC is the 2-port member of the Cisco multichannel T3 port adapters, for the Cisco 7200 Series routers and the Cisco 7301 router. Its spare form is the PA-MC-2T3-EC=, and the 1-port sibling is the PA-MC-T3-EC.

Each T3 interface can be set on its own to multichannel T3 or to clear-channel packet-over-T3. In multichannel mode one T3 carries up to 28 T1 links, and each T1 can be split down to DS-0. In clear-channel mode the interface runs as an unchannelized 45-Mbps T3 for full-rate or subrate DS-3 service. Each port has dual female 75-ohm BNC connectors for separate receive and transmit, with B3ZS line coding and C-bit parity or M23 framing.

Multilink PPP, Multilink Frame Relay, link fragmentation and interleaving, and FRF.12 run on the adapter and not on the router CPU. Up to 168 MLPPP or MLFR bundles are available across the two interfaces, each with up to 12 T1 links, and no fractional T1 is allowed in a bundle. Up to 128 serial data channels are supported per interface, with Frame Relay, PPP and HDLC encapsulation, and the MTU can reach 9000. Cisco 7204VXR and 7206VXR chassis take 6 of these adapters plus 1 in the jacket card with NPE-G1 or NPE-G2, and the 7201 and 7301 take 1. Channelized E3 is not supported. Further port adapters sit in Cisco interface cards.