[e2e] TCP losses

[Lars Eggert]

Fred Baker wrote:
> At 10:54 AM 02/28/05 +0100, Sireen Habib Malik wrote:
> 
>> How long does TCP take to decide that its connection has gone to the 
>> dogs and that the Application must do something about it? RFC1122 
>> (section 4.2.3.5) talks about "atleast" 100seconds. Is this applied 
>> practically?
> 
> By some, yes, and often not. Practically, a routing outage lasting for 
> tens of seconds often results in TCP sessions failing. I'm not sure I 
> would peg it to 100 seconds nowadays, but some do seem a little brittle.

FYI, we have a draft in the TCPM working group that lets TCP choose 
per-connection timeouts in addition to the system wide default, with the 
idea that you'd use longer timeouts for "important" connections.

ftp://ftp.rfc-editor.org/in-notes/internet-drafts/draft-eggert-gont-tcpm-tcp-uto-option-01.txt

Lars
-- 
Lars Eggert                                     NEC Network Laboratories
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/x-pkcs7-signature
Size: 3360 bytes
Desc: S/MIME Cryptographic Signature
Url : http://www.postel.org/pipermail/end2end-interest/attachments/20050301/50460524/smime.bin