A case for TCP Vegas in high-performance computational grids

Computational grids such as the Information Power Grid [1], Particle Physics Data Grid [2], and Earth System Grid [3] 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 [4, 5, 6, 7, 8, 9, 10, 11, 12, 13], 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 a and. Our results exhibit ways to significantly enhance the performance of distributed computational grids that rely, on TCP.