Nortel DMS-100 Series Maintenance Manual page 94

1-78 Maintenance overview
Scenario 5
All DS-1 links, which includes the protection link, are in-service. Faults are
not present on any link.
Scenario 6
All DS-1 links, which includes the protection link, are in-service. Faults are
not present on any link.
297-8231-550 Standard 09.01 August 1998
A protection switch does not occur. The C-link is system busied.
The RCS detects a fault on the A-link.
A protection switch does not occur. The A-link is system busied.
Note: If the RCS is in Mode II or III, the RCS is system busied because
all DS-1 links are out-of-service.
The SMS detects a fault on the C-link.
The C-shelf is protection switched.
The SMS detects a fault on the A-link.
The protection link is dropped from the C-shelf. The protection link
switches to the A-shelf. The C-link is system busied.
The SMS detects a fault on the C-link.
The C-shelf is protection switched.
The SMS detects a fault on the B-link.
The protection link remains switched on the C-shelf. The B-link is
system busied.