31 Aug
2015
31 Aug
'15
8:49 p.m.
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