CHAPTER
7-1
Cisco ONS 15454 SDH Reference Manual, R5.0
April 2008
7
Card Protection
This chapter explains the Cisco ONS 15454 SDH card protection configurations. To provision card
protection, refer to the Cisco ONS 15454 SDH Procedure Guide.
Chapter topics include:
7.1 Electrical Card Protection, page 7-1
7.2 STM-N Card Protection, page 7-4
7.3 Unprotected Cards, page 7-4
7.4 External Switching Commands, page 7-5

7.1 Electrical Card Protection

The ONS 15454 SDH provides a variety of electrica l card protection methods. This section describes the
protection options.

7.1.1 1:1 Protection

In 1:1 protection, a working card is paired with a protect card of the same type. If the working card fails,
the traffic from the working card switches to the protect card.When the failure on the working card is
resolved, traffic automatically reverts to the working card. Figure7-1 shows the ONS 15454 SDH in a
1:1 protection configuration; Slot 2 is protecting Slot 1, Slot 4 is protecting Slot 3, Slot 17 is protecting
Slot 16, and Slot 15 is protecting Slot 14. Each working card i s paired with a protect card. Slots 6 and
12 are not used for electrical cards. They have no corresponding Front Mount Electrical Connection
(FMEC) slots.