Switching of paths in Diamond circuits

The process of switching paths in the diamond circuits is as follows:

1. Select work (say Path W1, where W1 is the original work path), protect (say P1, where P1 is the original protect path) and backup path (say B1, where B1 is the original backup path) for the circuit.
2. When traffic affecting alarm is raised on work path, there should be no loss of traffic as protect path should become active due to SNCP switch.
3. On TJ5500, verify that protect path (P1) is active and original work (W1) and backup paths (B1) are swapped (i.e. original work path is transformed to backup and vice versa). The following changes are seen in the paths. The following changes are seen in the paths:
   • P1->P2 (where P2 is the same original protect path).
   • B1->W2 (where W2 is the new switched work path).
   • W1->B2 (where B2 is the new switched backup path).
4. TJ5500 raises appropriate alarm whenever two of the three paths are defunct or left unprotected.
5. TJ5500 raises a traffic loss alarm whenever all three paths of diamond service are either unavailable or not functioning properly.