A case for TCP Vegas in high-performance computational grids

Computational grids such as the Information Power Grid (Johnston et al., 1999), Particle Physics Data Grid , and Earth System Grid depend on TCP to provide reliable communication between nodes across a wide-area network (WAN). Of the available TCP implementations, TCP Reno and its variants are the most widely deployed; however, Reno's performance in computational grids is mediocre at best. Due to conflicting results in the evaluation of TCP implementations, we present a detailed simulation study that unifies the conflicting results and demonstrates the limitations of earlier work. We focus on the two most debated versions of TCP-Reno and Vegas. Using real traffic distributions, we show that Vegas performs well over modern high-performance links and better than Reno with the proper selection of the Vegas parameters /spl alpha/ and /spl beta/. Our results exhibit ways to significantly enhance the performance of distributed computational grids that rely on TCP.