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From: Mills@UDEL.EDU
Newsgroups: comp.protocols.tcp-ip
Subject: Re:  Internet Protocol #77
Message-ID: <8707131311.a011655@Huey.UDEL.EDU>
Date: Mon, 13-Jul-87 13:11:50 EDT
Article-I.D.: Huey.8707131311.a011655
Posted: Mon Jul 13 13:11:50 1987
Date-Received: Wed, 15-Jul-87 00:41:46 EDT
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Chris,

Is "protocol number 77" expressed in octal or decimal? Protocol number 63
(decimal) or 77 (octal) is reserved for local use, according to the assigned-
numbers list. My interpretation of this is that gateways should not forward
IPgrams carrying this number, so the NSFNET Backbone gateways, at least, do
not; therefore, your traffic certianly did not rumble that way.

Having said this, I am somewhat concerned about loopback and other things
intended to have only local relevance and "never escape the local net." Some
things, in particular local routing information and local broadcasts seem
in tune with this notion, since they depend on addressing independent of
local-network characteristics. However, some others (ND, NFS?) depend on
the characteristics of the local net (delay, discard rate, etc.) as an intrinsic
requirement for acceptable service. The use of addressing scope to delimit
service range in such cases seems conuterproductive. What you really want is
scope determined by maximum acceptable delay; in other words, some mapping of
type-of-service plus maybe a new IP option. This is the same thing needed for
packet speech and, in fact, implemented in those gateways supporting the
Stream (ST) Protocol.

Dave