Once defined a default route, it is possible to stablish the switching criteria -or set of them- that the Compact SAE STM-64 1+1 Optical adapter takes into account before placing traffic on the alternative route. The options available are as follows:
- LOS (Loss of signal). Loss of signal at the RX port of the optical transceiver.
- Optical power received at the RX port of the optical transceiver defined below.
- Alarms RS TIM, MS-AIS and RDI
- Exceeding a threshold of block error rate (calculated by the bytes B1 and B2).
The response time to such events will never be greater than 50ms.
In addition, Compact SAE STM-64 1+1 has the following policies of redundancy in case of fail of the main fiber: reversible switching (back to the main route in recovery), non-reversible (staying in the switched path to new switching event on the route) and forced commutation (always same path, independent of the events).