Is Fragmentation at IP layer even needed ?

Alexey Eromenko <al4321@gmail.com> Sun, 07 February 2016 12:47 UTC

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From: Alexey Eromenko <al4321@gmail.com>
Date: Sun, 7 Feb 2016 14:47:21 +0200
Message-ID: <CAOJ6w=EvzE3dM4Y2mFFR=9YyPBdmFu_jkF4-42LjkdbRd3yz_w@mail.gmail.com>
Subject: Is Fragmentation at IP layer even needed ?
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Hi All,

I'm re-evaluating TCP/IP stack again with my ongoing IP-FF research.

My question: Is packet fragmentation at IP layer even needed ?

Basically here are few possibilities:

1. Fragmentation-and-reassembly at every hop. (I don't know if anybody
implements it)
2. IPv4 style-fragmentation -- fragmentation per every hop, reassembly at
destination end.
3. IPv6-style-fragmentation -- fragmentation only at source end, reassembly
at destination end.
4. No fragmentation at all (the advantage here: faster Router processing vs
#1 or #2 and less implementation bugs); Assuming standard packet size is
defined at 1280 bytes, like in IPv6
5. MTU path discovery via ICMP -- RFC-1981
6. MTU path discovery via TCP (or other Transport) -- RFC-4821 (or other
way)

I'm leaning towards 4 + 6 solution in my own protocol, IP-FF.
What do you think ?
Should IP layer provide fragmentation ?

-- 
-Alexey Eromenko "Technologov"