6.2 mtu now limits size of incomming packet
Stephen.Clark at seclark.us
Sat Jul 21 16:28:31 UTC 2007
Artyom Viklenko wrote:
>Artem Belevich wrote:
>>Here's one example where MTU!=MRU would be useful.
>>Think of asymmetric bandwith-limited ADSL links. Lower MTU would allow
>>lower TX latency for high priority packets when upstream is saturated,
>>yet large MRU on the downstream would be great for downloads.
>>Right now with 6.2 one has to trade off lower latency for faster download.
>You can prioritize small packets with ACKs, for example, by other
>techniques - ALTQ one of them.
>Unconditional lovering MTU even on ADSL tend to loss throughtput.
>And let's think about TCP MSS. When TCP connection establishes,
>TCP stack uses MTU as measure to choose MSS.
>Any two hosts, connected to single Layer2 network MUST use
>same MTU. Any other cases lead to hard-to-solve problems.
>This is all IMHO. But I would not like to see different
>MTU and MRU on my Ethernet interfaces! :)
Yes but the mss is what the endpoints in the connection know about their
at this point there is no knowledge of the mtu/mru's of intermediate
"They that give up essential liberty to obtain temporary safety,
deserve neither liberty nor safety." (Ben Franklin)
"The course of history shows that as a government grows, liberty
decreases." (Thomas Jefferson)
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