Cisco Systems MGX 8220 HSSI Back Cards, Redundancy Back Cards

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Cisco MGX 8220 Installation and Configuration
Release 5.0, Part Number 78-6430-03 Rev. D0, November 2003
Chapter Service Module Back Cards
HSSI Back Cards
The HSSI (High-Speed Serial In te r face ) ba ck card supports two HSSI ports usi ng a fe mal e SCSI-II
connectors.
DTE-to-DCE control is achieved through combination software controls and a “NULL MODEM”
connector.
Redundancy Back Cards
When the SRM is used to provide 1:N redun dancy for T1/E1 service modules, the standby (redundant)
card set uses a special redundancy ba ck ca rd . The re are three types of 4-port redundancy bac k car d s:
R-DB15-4T1, R-DB15 - 4E 1 , a n d R - BNC-4E1. There are th r e e t y pes of 8-port redundan c y ba ck cards:
R-RJ48-T1-BC, R-RJ48-E1-BC, and R-SMB-E1-BC. The one you use depends upon the number of
ports, the line type (T1 or E1), and the connector type (RJ-48, DB-15 or BNC) of your service module.
(See Figure 4-16 and F i gu re 4-17.) When 1:N re d u nd ancy is invoked, the physi cal lines to the failed
service module back c ard are still used. However, the signals are still routed to and from the redundant
back card.