[e2e] tcp connection timeout

David P. Reed dpreed at reed.com
Tue Mar 7 07:38:29 PST 2006

Because NAT doesn't work, we have to change all the perfectly correct 
TCP stacks and make keepalives the standard.  And to make NATs more 
memory efficient, we should make the default keepalive interval 100 
msec. lest the "losers" who write applications open a lot of connections 
and forget to close them.

I suppose that is reasonable, given that NAT has become the Internet 
architecture by default.   Certainly IPv6 is stillborn in the US 
residential and corporate market.

Perhaps we should next move to the true future: IBM SNA 2007.   The 
future will be about putting the semantics of unit record devices into 
the routers.  All hail Physical Unit Type 2.

Tim Dorcey wrote:
>> What is the point of having a long-lived TCP session with
>> keepalive in the 21st century?
> One possible consideration is that many applications operate over a network
> where traffic is not allowed to flow in one direction unless traffic has
> recently been sent in the other direction.  I am thinking of NAT's and
> firewalls.  If an application wants a host "outside" the NAT/firewall to be
> able to send something to it at an arbitrary time, there seems no other
> option then to periodically send something out to it.  Since these devices
> often operate at the transport level, there might be some rational for
> putting this functionality in the host transport layer.
> Tim

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