Datensatz

Zusammenfassung

This paper proposes Monarch, a novel tool that accurately emulates transport protocol flows from an end host controlled by its user to any other Internet host that responds to simple TCP, UDP, or ICMP packet probes. Since many Internet hosts and routers respond to such probes, Monarch can evaluate transport protocols, such as TCP Reno, TCP Vegas, and TCP Nice, over a large and diverse set of Internet paths. Current approaches to evaluating these protocols need control over both end hosts of an Internet path. Consequently, they are limited to a small number of paths between nodes in testbeds like PlanetLab, RON or NIMI. Monarch's ability to evaluate transport protocols with minimal support from the destination host enables many new measurement studies. We show the feasibility of using Monarch for three example studies: (a) understanding transport protocol behavior over network paths that are less explored by the research community, such as paths to cable and DSL hosts, (b) investigating the relative performance of different transport protocol designs, such as TCP Vegas and TCP Reno, and (c) testing protocol implementations under a wide range of experimental conditions.