Enterasys Networks X-PeditionTM Overview, Features, T1/E1 Functionality, T3/E3 Functionality

4

Configuring T1/E1 & T3/E3 Interfaces

Overview

The XSR provides Frame Relay and PPP service via T1/E1 and T3/E3 functionality as well as Drop and Insert features.

T1/E1 Functionality

The XSR provides a T1/E1 subsystem on a single NIM-based I/O card with a maximum of two installed NIMs. Depending on the card type and series, each card can support 1, 2 or 4 T1 or E1 physical ports.

You can select either T1, at 1.544 Mbps interface rate per port, or E1, at 2.048 Mbps interface rate per port. In both operational modes, the interface can work either in full rate T1/E1 mode (the complete available line interface rate is assigned to one user), fractional T1/E1 mode (only one channel group is assigned, with less than the total available number of timeslots on a T1/E1 line configured per physical port) or in channelized mode (more than one channel group is configured per physical port).

In fractional/channelized mode, up to 31 DS0 channels can be assigned on E1 interfaces and up to 24 DS0 channels can be assigned on T1 interfaces. The rate (line speed) of basic channel (DS0) can be configured at 56 or 64 Kbps.

T3/E3 Functionality

The XSR T3/E3 subsystem offers a NIM-based I/O card with a single port, full rate unchannelized T3/E3 mode and sub-rate support for proprietary T3 and E3 DSU vendors. “Sub-rate T3/E3” and “fractional T3” are interchangeable terms describing un-channelized T3/E3 service that delivers less than full line bandwidth.

T3 or E3 mode is software selectable - one hardware NIM supports both modes.

Features

T1/E1 Mode

The following features are offered on the T1/E1 interfaces:

•Integrated CSU/DSU

•Full-rate, channelized and fractional

•Short and long haul symmetrical line interfaces with 100/120 ohm impedance using RJ-45/ 48C or 49C connectors

XSR User’s Guide 4-1