PMTUD for IPv4 Multicast - How?
Masataka Ohta
mohta at necom830.hpcl.titech.ac.jp
Tue Sep 1 00:49:47 UTC 2015
William Herrin wrote:
>> for routers, generating ICMP PTB is as burdensome
>> as generating fragments?
>
> No, it isn't.
Yes, it is. Generating an ICMP PTB @aclet is as burdensome as
fragmenting a packet.
> When a router fragments a packet, it has to fragment the next and the
> next and the next. Maybe tens or hundreds of thousands of packets
> before the end of that one user's session.
Not necessarily, because transport layer can react against fragmented
packets.
> When a router generates a PTB, there is no next. PTB is a soft
> failure. The origin must correct the error (by reducing packet size)
What if, the origin does not reduce packet size?
Masataka Ohta
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