File Transfer in Fcs Networks Using Transport Layer Multistreaming*

We identify overheads associated with the current FTP protocol, which uses TCP for transport. We discuss why using TCP to avoid such overheads puts a burden on the application. Unlike TCP, SCTP allows transport layer multistreaming within a single association. We present two modifications to FTP, which use SCTP multistreaming in a “TCP-friendly” manner. Our modifications avoid the identified overheads in the current FTP protocol without introducing complexity at the application. We have implemented these modifications in the FreeBSD environment. Extensive emulations have been carried out to compare the current FTP design with the modifications introduced, in terms of end to end latency. Our results indicate dramatic improvements in transfer time and throughput achieved between two endpoints under certain network conditions.