A new Request for Comments is now available in online RFC libraries. RFC 1323: Title: TCP Extensions for High Performance Author: V. Jacobson, R. Braden, & D. Borman Mailbox: van@CSAM.LBL.GOV, Braden@ISI.EDU, dab@cray.com Pages: 37 Characters: 84,558 Obsoletes: RFC 1072, RFC 1185 This memo presents a set of TCP extensions to improve performance over large bandwidth*delay product paths and to provide reliable operation over very high-speed paths. It defines new TCP options for scaled windows and timestamps, which are designed to provide compatible interworking with TCP's that do not implement the extensions. The timestamps are used for two distinct mechanisms: RTTM (Round Trip Time Measurement) and PAWS (Protect Against Wrapped Sequences). Selective acknowledgments are not included in this memo. This memo combines and supersedes RFC-1072 and RFC-1185, adding additional clarification and more detailed specification. Appendix C summarizes the changes from the earlier RFCs. This is now a Proposed Standard Protocol. This RFC specifies an IAB standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "IAB Official Protocol Standards" for the standardization state and status of this protocol. Distribution of this memo is unlimited. Requests to be added to or deleted from this RFC-DIST distribution list should be sent to RFC-REQUEST@NIC.DDN.MIL. RFCs can be obtained via FTP from FTP.NISC.SRI.COM, NIS.NSF.NET, NISC.JVNC.NET, VENERA.ISI.EDU, WUARCHIVE.WUSTL.EDU, SRC.DOC.IC.AC.UK, FTP.CONCERT.NET, or NIC.DDN.MIL. Details on obtaining RFCs via FTP or EMAIL may be obtained by sending an EMAIL message to "rfc-info@ISI.EDU" with the message body "help: ways_to_get_rfcs". For example: To: rfc-info@ISI.EDU Subject: getting rfcs help: ways_to_get_rfcs Requests for special distribution should be addressed to either the author of the RFC in question, or to NIC@NIC.DDN.MIL. Unless specifically noted otherwise on the RFC itself, all RFCs are for unlimited distribution. Submissions for Requests for Comments should be sent to RFC-EDITOR@ISI.EDU. Please consult RFC 1111, "Instructions to RFC Authors", for further information. Joyce K. Reynolds USC/Information Sciences Institute ======================================================================