The File Transfer Service (FTS) is a very important service within WLCG grid. This product acts as a network queue so allowing file transfers to be more efficient as by queuing requests, each request should take less time. Since the network usage can be partitioned by VO this prevents any VO from overloading the system and adversely effecting others performance.

FTS servers work with a series of channels, each with a queue. A channel is typically configured for point to point transfers. FTS is currently deployed only at major sites and is outside the scope of this workshop; however, sites should be aware that the majority of data transfers should be controlled by FTS.