NM-1T3/E3 Cisco 1-Port T3/E3 Network Module

The NM-1T3/E3 is a Cisco one-port clear-channel T3/E3 network module for WAN links. One Cisco IOS command switches the port between T3 and E3 operation, and an integrated line interface unit and DSU lets the line terminate directly on the router with no external DSU.

Each port is a DSX3-level interface with a pair of 75-ohm BNC coaxial connectors (Type RG-59), one for transmit and one for receive, plus six LED indicators for line status. Line speeds are 44.736 MHz full duplex for DS3 and 34.368 MHz full duplex for E3. Line build-out is programmable for up to 450 feet of 734A coaxial cable or up to 225 feet of 728A.

C-bit or M23 framing is available for T3, and bypass or G.751 framing for E3, with B3ZS line coding on T3 and HDB3 on E3. Serial encapsulations are HDLC, PPP and Frame Relay, and scrambling and subrate settings follow the Digital Link, Kentrox, Larscom, Verilink and Adtran DSU algorithms.

The module is single-wide with no slot restrictions and measures 1.55 x 7.10 x 7.2 inches (3.9 x 18.0 x 18.3 cm). It runs in every Cisco IOS feature set with no additional memory. Cisco 2650, 2651XM, 2691, 2800, 2951, 3661, 3662, 3725, 3745, 3825, 3845, 3925, 3925E, 3945 and 3945E routers take it; the 3845, 3945 and 3945E hold two modules and the others one, and the 3925 and 3945 series use the SM-NM-ADPTR network module adapter card. The store also has the CISCO3825 integrated services router.

More WAN modules and cards for Cisco access routers are in Cisco interface cards, and the routers that host them are in Cisco routers.