LinuxDig.com Request For Comments

RFC Number : 449 Title : Current flow-control scheme for IMPSYS. Network Working Group Dave Walden RFC # 449 BBN-NET NIC # 14133 Jan. 6, 1973 Updates RFC 442 The Current Flow-control Scheme for IMPSYS. While Vint's notes on IMPSYS flow-control from the March 16, 1972, meeting (RFC 442) seem reasonably accurate and while he does cite our Quarterly Technical Report #13, he might have done better to cite BBN's two formal publications relevant to the IMPSYS flow-control scheme: 1. McQuillan et al, Improvements in the Design and Performance of the ARPA Network, Proceedings AFIPS 1972 FJCC, pp. 741-754. 2. BBN Report 1822, Specifications for the Interconnection of a Host and an IMP, December 1972 Revision, section 3, pp. 17-35. Reference 2 is particularly important reading for NCP programmers - things have recently changed somewhat. The inter-IMP acknowledgement mechanism, described in the last section of Vint's RFC 442, is also described in reference 1 and an almost identical mechanism is described in Appendix F of reference 2. The acknowledgement is of only intellectual interest to most Hosts as it is transparent to network users. However, the description in reference 2 is of vital interest to so-called Very Distant Hosts. [ This RFC was put into machine readable form for entry ] [ into the online RFC archives by Alex McKenzie with ] [ support from GTE, formerly BBN Corp. 9/99 ] Walden [Page 1]