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/rfc613.txt | 59 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 59 insertions(+) create mode 100644 doc/rfc/rfc613.txt (limited to 'doc/rfc/rfc613.txt') diff --git a/doc/rfc/rfc613.txt b/doc/rfc/rfc613.txt new file mode 100644 index 0000000..f995ed9 --- /dev/null +++ b/doc/rfc/rfc613.txt @@ -0,0 +1,59 @@ + + + + + + +Network Working Group Alex McKenzie +RFC # 613 BBN-NET +NIC # 21525 January 21, 1974 + + + Network connectivity: A response to RFC #603 + +Network topology is a complicated political and economic question with +obvious technical overtones. I shall not attempt, in this note, to +cover all the possible arguments which might be made, but merely to +respond directly to the points raised in RFC #603. + + 1. The important consideration in deciding whether it is good or + bad to have a node (AMES) be four connected is not how many circuits + are affected by a node failure; rather one should consider how well + the network is still connected after a node failure. For example, + if ALL nodes in the network were four-connected I doubt that anyone + would argue that this was bad for reliability. The weaknesses are + not the three-connected and four-connected nodes but rather the + ONE-connected (Hawaii, London) and two-connected nodes. I must + agree with Burchfiel's implied argument that it is better to have + two adjacent three-connected nodes than to have a four-connected + node adjacent to a two-connected node; unfortunately the realities + of installing interfaces and common carrier services cause the + Network to expand in sub-optimal ways. + + 2. "Loops" are not good per se, they appear good because the act of + making loops increases the connectivity and thereby reduces the + effect of multiple failures. Adding more circuits costs ARPA money, + both capital cost for IMP interfaces and recurring cost for the + circuits. The network group at BBN has suggested to ARPA several + times that "connectivity should be increased" but it was only late + in December 1973 that we made specific suggestions for the locations + of additional circuits. These recommendations were not based on + building loops (although they may have that effect) but were based + on breaking the long chains of IMPs which have occurred as the + Network has grown. ARPA and NAC are now presumably in the process + of evaluating our suggestions, and perhaps formulating other + possibilities. + + + + + + [ 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. 10/99 ] + + + + +McKenzie [Page 1] + -- cgit v1.2.3