From 4bfd864f10b68b71482b35c818559068ef8d5797 Mon Sep 17 00:00:00 2001 From: Thomas Voss Date: Wed, 27 Nov 2024 20:54:24 +0100 Subject: doc: Add RFC documents --- doc/rfc/rfc19.txt | 112 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+) create mode 100644 doc/rfc/rfc19.txt (limited to 'doc/rfc/rfc19.txt') diff --git a/doc/rfc/rfc19.txt b/doc/rfc/rfc19.txt new file mode 100644 index 0000000..aa483e4 --- /dev/null +++ b/doc/rfc/rfc19.txt @@ -0,0 +1,112 @@ + + + + + + +Network Working Group John E. Kreznar +Request For Comments: 19 SDC + 7 October 1969 + +Two Protocol Suggestions to Reduce Congestion at Swap-Bound Nodes + +There is a wide variance in swap rates between core and auxiliary store +among the HOST systems to be nodes in the ARPA IMP network. The slower +of these, of which our 360/50 system with 2303 drump swap store is an +example, might improve the utility of the network not only for +themselves but for all nodes if the two protocol suggestions of this +note were to be adopted. + +1. HOST control of ordering of IMP-to-HOST traffic. IMP-HOST protocol + now calls for delivery of messages from IMP to HOST in the order in + which the IMP received them. This may lead to wasted swapping if, + for example, the IMP has messages for its HOST's timeshare users A + and B, in that order, at a time when user B is in HOST core. B + would have to be swapped out, A in, and the first message accepted-- + only to discover that now A must be swapped out and B back in again. + If the HOST could a) read the IMP's queue of waiting messages and b) + accept them in the order it found most effective, then a new + mechanism for improvement of network efficiency would be at hand. + Clearly this change would have an impact on BBN's IMP software. + +2. Core-to-core transfers between HOSTS. At another level, perhaps not + involving HOST-IMP protocol or IMP software changes, is a HOST-HOST + protocol wherein cooperating HOSTS agree to lock appropriate + programs in core for the duration of a multi-message file transfer + on an auxiliary connection. This could greatly reduce the time to + transfer such a file to and from a swap-bound HOST. Unfortunately, + the numbers mitigate possible advantages of this approach to some + extent: if we assume a 50 kilobit/sec line and support further that + it is dedicated at 100% efficiency to this transfer (which may + require slightly different handling of RFNMs in this case) this + comes out to just over 6 8-kilobit messages per second. It may be + impolitic in a timeshare environment to lock a single program in + core for more than about 2 seconds. If this is the case, then the + method would be applicable only for the rather limited range of file + sizes of 2-16 messages. Nevertheless, the time to move a large file + could be so greatly enhanced by this approach that I think it + deserves consideration. + + +1. Abhi Bhushan, Proj. MAC 10. Jerry Cole, SDC +2. Steve Crocker, UCLA 11. John Kreznar, " +3. Ron Stoughton, UCSB 12. Dick Linde, " +4. Elmer Shapiro, SRI 13. Bob Long, " + + + + [Page 1] + +5. Steve Carr, Utah 14. Reg Martin, " +6. John Haefner, RAND 15. Hal Sackman, " +7. Paul Rovner, LL 16. C. Weissman, " +8. Bob Khan, BB & N 17. Marty Bleier, " +9. Larry Roberts, ARPA + + + + [ This RFC was put into machine readable form for entry ] + [ into the online RFC archives by Alex Portnoy 1/97 ] + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + [Page 2] + -- cgit v1.2.3