CHAPTER
3-1
Cisco ONS 15600 Reference Manual, R7.2
3
Card Protection
Note
The terms "Unidirectional Path Switched Ring" and "UPSR" may appear in Cisco literature. These terms
do not refer to using Cisco ONS 15xxx products in a unidirectional path switched ring configuration.
Rather, these terms, as well as "Path Protected Mesh Network" and "PPMN," refer generally to Cisco's
path protection feature, which may be used in any topological n etwork configuration. Cisco does not
recommend using its path protection feature in a ny particular topological network configuration.
This chapter explains the Cisco ONS 15600 card protection co nfigurations.
Chapter topics include:
3.1 Optical Port Protection, page 3-1
3.2 Unprotected Ports, page 3-3
3.3 External Switching Commands, page 3-3

3.1 Optical Port Protection

When you set up protection for ONS 15600 cards, you m ust choose between maximum protection and
maximum port availability. The highest protection reduces the number of available ports; the highest
port availability reduces the protection. Tabl e 3- 1 contrasts port protection with an unprotected scheme.