Optical Technologies
Burst Switched Network

Alternative to the synchronous network is burst switched network. This approach is similar to contemporary Internet, where packets are of various lengths. Therefore, they can enter the node anytime and there is no necessity for synchronization.

Burst switch architecture

Comparing to synchronous switching, burst switching introduces more flexibility but also new problem. This problem is temporal concurrence, which should be resolved.

In synchronous networks, only spatial (which fiber) and spectral (which lambda) problems were to be solved in each time-slot. In burst network, there is no notion of time-slot and consequently packets should be ordered one after another. Even more, packets are of variable length. In the situation when one packet is blocking outgoing port, another one should wait in the delay lines. From this point of view, delay lines should be significantly smaller than mean packet length. Several enhancements have been proposed to improve performance of burst network. Majority of them consists in introducing new protocol for path reservation.