Here's some information about the MYLAPS timing system.

Server

This is the heart of the system, the software for operating the system and the decoders connect to it

Decoder

This is connected to the wire in the track and detects the transponders. Then sends all that information to the server.

Yellow wires

Part of these need to be laid in the track, part of it is used to connect the wires in the track to the decoder.
Only the part in the track detects transponders, the rest of it doesn't.

Transponder

This attaches to each bike. The timing software needs to be told the number written on it and which rider's bike it is on