Compressed Routing Header idea

"Templin (US), Fred L" <> Mon, 18 May 2020 14:05 UTC

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From: "Templin (US), Fred L" <>
To: IPv6 List <>
Subject: Compressed Routing Header idea
Thread-Topic: Compressed Routing Header idea
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Date: Mon, 18 May 2020 14:03:56 +0000
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Hi, I have a use case where some IPv6 addresses that would go into a routing header are
more compressible than others and so I am wondering if some kind of "hybrid" compressed
routing header would be possible. For example, if one address can be compressed down to
16 bits, then include only those 16 bits; if a different address can only be compressed down
to 32 bits, then include the 32 bits; if yet a different address cannot be compressed at all,
then include all 128 bits. And, there may be many more sizes in between.

RFC4191 Section 2.3 shows an example of how an IPv6 prefix/address can be compressed
to a variable length. Essentially, a length byte followed by a variable-length prefix. That way
there would still be "pretty good compression" albeit with an extra byte per prefix. And, it
would be a generalized form that would only require a single routing header type value.
How would it be if we did something like that?