NAT444 or ?
Jean-Francois.TremblayING at videotron.com
Jean-Francois.TremblayING at videotron.com
Wed Sep 7 20:12:12 UTC 2011
>> However these are with a very high address-sharing ratio (several
>> thousands users per address). Using a sparser density (<= 64 users per
>> address) is likely to show much less dramatic user impacts.
>
> I think you have the numbers off, he started with 1000 users sharing
> the same IP, since you can only do 62k sessions or so
These numbers were not off. From page 19: "...we should assign at least
1000 [..] ports per customer to assure good performance of IPv4
applications"
"At least 1000 ports per customers" is roughly the same than "less than
64 users per address" as I stated above.
Btw, 90% of subscribers have less than 100 active connections at any time,
if I read these tiny graphs correctly:
http://www.wand.net.nz/~salcock/pam2009_final.pdf
> and with a "normal" timeout on those sessions you ran into issues
quickly.
Agreed for UDP, but most of these sessions are TCP, which arguably time
out
rather rapidly after a FIN and an extra hold time. Normal duration of a
TCP
session is usually under a few seconds.
This study saw an average connection time of 8 seconds for DSL, but it's
from 2004.
http://www.google.com/#q=A+Comparative+Study+of+TCP/IP+Traffic+Behavior+in+Broadband+Access+Networks
/JF
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