Patent ID: 6925054

Claim:
A method of transporting packet communications traffic between first and second nodes in a communications packet network carrying high priority traffic and lower priority traffic, said first node having a first output port to which the high priority traffic is permanently allocated and a second output port to which the lower priority traffic is permanently allocated, said first and second output ports being coupled to respective first and second input ports at said second node via a transport medium comprising first and second crossover switches and first and second substantially identical paths therebetween, the method comprising; at the first node, identifying the higher and lower priority packets in the traffic, outputting the high priority packets of the traffic at the first output port and outputting the lower priority packets of the traffic at the second output port; transporting the high priority traffic via the first crossover switch, the first path and the second crossover switch to the first input port at the second node, transporting the lower priority traffic via the first crossover switch, the second path and the second crossover switch to the second input port at the second node; at the second node, receiving the high priority traffic at the first input port and the lower priority traffic at the second input port; monitoring the integrity of the first path and, in the event of a fault on that first path, operating said first and second switches so as to transport the high priority traffic on the second path and the lower priority traffic on the first path between the switches.