In this protection scheme, a single device, Card or Equipment, protects up to 14 others in the same shelf. The type of card or equipment and the number of ports in the card or equipment located in the protection slot must be the same as that of the number of working devices that it protects. When a failure occurs on a working device, the protection device takes on the role of the working device. All of the facilities connected to the ports on the working device use the ports on the protection device. The 1:N protection scheme is shown in 1:N protection scheme.

This protection scheme does not deal with the failure of multiple devices; however, a priority scheme would allow protection of the highest priority working device.

Figure 1. 1:N protection scheme