Cisco Systems MGX 8230 manual Types of Frame Service Modules, FRSMs for T1 and E1 Lines

Chapter 2 Module and Service Descriptions

Frame Relay Service Modules

Congestion Indication

The FRSM maps congestion indication in both directions:

Congestion Indication mapping is provided in both directions

FUNI-to-ATM Direction

EFCI is set to 0 for every ATM cell generated by the segmentation process.

ATM-to-FUNI Direction

If the EFCI field in the last ATM cell of a received segmented frame is set to 1, the CN bit in the FUNI header is set to 1. The two reserve bits (the same positions as C/R and BECN in Frame Relay header) are always set to 0.

Types of Frame Service Modules

There are three types of FRSMs:

•FRSMs for T1 and E1 Lines, page 2-27.

•FRSMs for T3 and E3 lines, page 2-32.

•FRSMs for Serial Connections, page 2-38.

Note For hardware and other specifications on the FRSMs, refer to Appendix A, “Technical Specifications.” For descriptions of how to configure the card, lines, and ports and add Frame Relay connections, refer to Chapter 6, “Card and Service Configuration”

FRSMs for T1 and E1 Lines

The eight-port FRSMs for T1 or E1 lines support channelized or unchannelized service. These cards include the following:

•AX-FRSM-8T1: supports up to eight fractional T1 line interfaces.

•AX-FRSM-8E1: supports up to eight fractional E1 line interfaces.

•AX-FRSM-8T1-C: supports up to eight channelized T1 line interfaces.

•AX-FRSM-8E1-C: supports up to eight channelized E1 line interfaces.

FRSM for T1 features

The FRSM-8T1 and FRSM-8T1-C each provide eight T1 interfaces for full-duplex communications at up to 1.544 Mbps.

Each T1 line consists of an RJ-48, along with three LED indicators for line status. The FRSM-8T1 supports fractional and unchannelized T1 port selection on a per-T1 basis. The FRSM-8T1-C allows full DS0 and n x DS0 channelization of the T1s, for a maximum of 192 ports per FRSM-8T1-C.

Key Features include:

•Eight T1 (1.544 Mbps +/-50 bps or 32 ppm) lines

•B8ZS or AMI line coding

•ANSI T1.408 extended superframe format line framing

	Cisco MGX 8230 Edge Concentrator Installation and Configuration
Release 1.1.31, Part Number 78-11215-03 Rev. B0, May 2001		2-27