Cisco Systems MGX 8220 Circuit Emulation Service Module (8-port)

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Cisco MGX 8220 Installation and Configuration
Release 5.0, Part Number 78-6430-03 Rev. D0, November 2003
Chapter Circuit Emulation Service Modules
Circuit Emulation Service Module (8-port)
The 8-port Circuit Emulat ion Service Module (CESM) is a two-card set consisting o f an CESM function
module front card and either a 8-T1 or a 8-E1 line module back card. T1 lines u se RJ48 connectors, E1
line module cards use either RJ48 or SMB connector types. The possible line modules are
•AX-RJ48-8T1-LM
•AX-R-RJ48-8T1-LM
•AX-RJ48-8E1-LM
•AX-R-RJ48-8E1-LM
•AX-SMB-8E1-LM
•AX-R-SMB-8E1-LM
Up to 10 CESMs may be inst alled in a shelf in slots 5 through 14. For T1 line versions, 1:N redundancy
is supported either through redundant line modules or through the SRM-T1E1 board. Likewise, for
T1/E1 versions, BERT and loopbacks are supported using the SRM.
A 1:N redundancy for E1 version is provided through redundant line modules only.
The main function of the CESM cards is to provide a constant bit rate (CBR) service for T1/E1 ports
over ATM network.
The CESM converts DS1/E1 or da ta s tr eam s into CBR AAL1 cells for t r an spo r t a c ros s th e ATM
network. The T1/E1 versions support a choice of structured or unstructured data transfer on a
per-physical-inter fa c e basis.
The CESM card supports loopback diagnostics features through the addlnloop command.
Note The addchanloop command is not supported in the 8-port CESM.
Refer to the Cisco MGX 8220 Command Reference for details of these commands .
T1/E1 Structured Data Transfer
The T1/E1 structured data transfer mode supports
•Synchronous timing only.
•A nx64 Kbps Fractional DS1/E1 serv ice wit h cont ig uous tim e sl ots . Any nx64 kbp s chann el can be
mapped to any VC. Both SF and ESF framing modes are supported.
•For AAL1 interworkin g co nversi on on ly, CAS ro b be d bit fo r T1 (A B CD fo r ESF a nd SF fram e s)
and CAS for E1 (Channel 16).
•CCS channel transparently a s d ata .
•Choice of partially filled cells.
•Idle Suppression/Detection for 1x64 CAS connections only.
T1/E1 Unstructured Data Tr ansfer
The T1/E1 unstructured data transfer mode supports:
•Both synchronous and asynchronous clocking.