Cisco Systems MGX 8230 Network Router User Manual


 
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Cisco MGX 8230 Edge Concentrator Installation and Configuration
Release 1.1.31, Part Number 78-11215-03 Rev. B0, May 2001
Chapter2 Module and Service Descriptions
Frame Relay Service Modules
CESM for T3 and E3 lines
The MGX-CESM-T3/E3 supports unstructured data transfer over a single T3 or E3 physical port at
speeds of 44.736 Mbps (T3) or 34.368 Mbps (E3). Only synchronous timing is supported.
MGX-CESM-T3/E3 is a two-card set consisting of a front card and either a T3 back card or an E3 back
card. Each back card provides two T3 or E3 ports (each port consisting of two BNC connectors). Only
port one is available on the back card when used with the CESM-T3/E3 front card. 1:1 redundancy is
supported through a Y-cable on the line module back cards.
Figure 2-26 on page 2-52 is an illustration of the MGX-CESM-T3/E3 front card.
An illustration of the CESM back card for T3 lines is shown in Figure 2-27 on page 2-53.
An illustration of the CESM back card for E3 lines is shown in Figure 2-28 on page 2-54.
CESM-T3/E3 Features
CESM cards support circuit emulation services using standards-based adaptation layers over ATM. The
CESM-T3E3 uses AAL1 for T3 or E3 unstructured transfer mode operation, per the ATM Forum's
Circuit Emulation Specification, Version 2.0:
Unstructured Support: supports T3/E3 unstructured data transfer.
Synchronous clocking: synchronous timing mode only supported. Must derive clock from shelf.
Onboard BERT: BERT support using on board BERT controller. BERT commands executed on
T3/E3 card.
Maximum number of connections: Maximum number of connections is one. In the unstructured
mode, one logical port is used to represent the T3/E3 line and one connection is added to the port to
emulate the circuit.
Programmable egress buffer size and CDV tolerance settings are supported for flexible support of
jitter and latency requirements.
Bit count integrity is maintained when AAL1 lost-cell condition is detected.
The CESM card provides ingress/egress data and signaling trunk conditioning per VC as per ATM
Forum CES V2.0.
T3/E3 CESM cards can be Y-cabled to provide 1:1 hot standby redundancy of the CESM.
CESM cards are supported by standards-based management tools, including SNMP, TFTP (for
configuration/statistics collection), and a command-line interface. The Cisco WAN Manager and
CiscoView tools also provide full graphical user interface management support.
T3 Interfaces
One DSX-3 (44.736 Mbps +/-40 ppm) interfaces with dual female 75-ohm BNC coaxial connectors
per port (separate RX and TX)
B3ZS line coding
Pulse shape conforming to ANSI T1.102
T3 bit error rate tester (BERT) and extended loop-up, loop-down pattern generation and verification
1:1 redundancy with Y-cabling for T3 CESM cards of the same type
LOS alarm detection/generation support
Transmitter loop-timed to receiver or synchronized to shelf