Short for Serializer/Deserializer. Within the switch, data moves in parallel chunks of 64 bits at a time. To move onto a wire (or fiber) the data words are serialized by being shifted out. When they arrive at their destination, that are deserialized back into internal word format.

The SerDes speed is the limiting factor in capacity and speed of silicon data switch engines. In Trident+ and Trident II, the SerDes run at 10 Gb/s and there are lots of them. 40 Gb/s ports are built with four lanes of 10 Gb/s each. These are made with 40 nM CMOS technology. With 28 nM processing, 25 Gb/s SerDes speeds will be possible.