Satellites are being used to extend the Global Internet geographically and will be more ubiquitous in the next decade with the deployment of several proposed services capable of providing greater than T1 access to individual users anywhere in the world. Yet, satellite links have a unique combination of characteristics that can affect the throughput of TCP traffic. Because of the high-bandwidth delay product, slow start and congestion control algorithms behave much differently when the path includes a satellite link than exclusively terrestrial ones. The TCP over Satellite Working Group shall produce an informational RFC which describes the issues affecting TCP throughput over satellite links. It identifies the domains in which each issue applies, including network topology, satellite orbit (LEO, MEO, GEO), and link rates; fixes, both protocol and implementation, that ameliorate reduced throughput; and areas for further research. The purpose of including this information is to direct the research community to the areas in which show promise, not to perform the research or even advocate the results. Scope: The scope of this working group will include consideration of the following for inclusion in the Informational RFC: o Transport layer issues affecting TCP over satellite links o Existing TCP options o Compliant implementations which have some known improved performance over satellite links o Recommendation of well understood protocol changes o Identification of protocol changes that are potentially promising but require more further investigation in order to be well understood SECURITY The working group will consider in depth security issues that are relevant, describing risks and indicating how they may be addressed.