Switching for Optical Signals

When communicating with large networks (like the internet), one of the most crucial factors that determines the speed of optical communications is the switching speed for optical signals.  Exploring such optical networks would require the channeling of data from one fiberoptic route to another.  There are two types of switch that permit such transfers.

1)         The Hybrid Switch

This switch connects channels by converting optical signals into electronic signals, switch the signal electronically, and retransmit an optical signal in the desired fiber.  Until recently, this approach to switching signals was the most popular for several reasons.  Though losing a considerable amount of speed capable in optical systems, electronic switching techniques were far more suited to handling high-bandwidth multi-channel signals.  With the capacity to easily cross-connect thousands of channels, these switches make up for what they lack in speed with their large capacity.

2)         All-Optical Switching

However, recent developments have allowed significant progress in creating switches that leave the optical signals unhindered.  Until the end of the 20^th century, data systems frequently used electronic hubs to switch signals.  However, as demands for capacity increased, hybrid systems could not keep up with the throughput.  Thus, these network hubs were the bottleneck in an optical system that could otherwise operate much more quickly.

In response to this demand, all-optical switches came into development.  Below is a table of different types of such switches and their switching times.