Implementation of the SNR high-speed transport protocol (the transmitter part)

Abstract

The major problem addressed by this research is how to implement a transport protocol invented especially for high speed networking using the current workstations, so that the high throughput promised by the protocol will be achieved. The approach taken was to implement the SNR protocol, a transport protocol for high speed networking, named after its inventors, and composed of eight different machines (four transmitter and four receiver), using three Unix workstations connected with FDDI, allowing a throughput up to 100 Mbps. This thesis is the implementation of the transmitter part of the protocol; the receiver part is done in parallel in a separate thesis. The four transmitter machines are implemented as four different Unix processes working in parallel and communicate through shared memory which provides the fastest means of exchanging information between processes. The protocol is implemented on top of the Internet Protocol layer using the "raw socket" as interface to access the IP facilities. The C programming language was used for the software implementation in order to access efficiently to the Unix system calls and thus reduce the overhead of the operating system. This thesis shows that these new protocols can be successfully implemented using the current workstations and we expect that in a multiprocessor environment, where each machine is dedicated to a different processor, we will have even better performance.