Re: [tcpm] TCP zero window timeout?
Mahesh Jethanandani <mahesh@cisco.com> Sat, 26 August 2006 00:02 UTC
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Date: Fri, 25 Aug 2006 17:00:13 -0700
From: Mahesh Jethanandani <mahesh@cisco.com>
Organization: Cisco Systems Inc.
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To: "Mahdavi, Jamshid" <jamshid.mahdavi@bluecoat.com>
Subject: Re: [tcpm] TCP zero window timeout?
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Cc: tcpm@ietf.org, "Anantha Ramaiah (ananth)" <ananth@cisco.com>, Fernando Gont <fernando@gont.com.ar>
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Jamshid, Looking at draft-ietf-tcpm-tcp-uto it appears that the draft is specifically looking at the question of disconnection in the network. It also applies to retransmission timer. The situation I was referring to is a little different and applies to persist timer. In our situation the client stops reading data. These clients are machines out in the Internet and as such the server has no control over their behavior. So while there is unacknowledged data, it is not that the client is not acking any data. It is responding to the probe but that it continuously advertises a window of zero. There is currently to my knowledge no timeout for this state for the server. This can manifest itself as a DOS situation if there are several such connections where the server is forced to hold data. We are suggesting a solution that allows the server to get out of this situation by applying a upper bound on the duration of the persist state. Note, it is not the default behavior for TCP. The default behavior is still the same. The user/administrator has to explicitly turn it on for the server to close the connection and free the resources in case it is believed that it is under attack. Fernando Gont wrote: > At 13:24 21/07/2006, Mahdavi, Jamshid wrote: > >> What is the status of draft-eggert-tcpm-tcp-abort-timeout-option-01? It >> may be of some use in situations like this. I've recently seen another >> scenario where this would be useful, so I'd be interested in seeing that >> draft reposted... > > > It was merged with draft-gont-tcpm-tcp-auto-option into > draft-ietf-tcpm-tcp-uto. > > The latest revision is draft-ietf-tcpm-tcp-uto-03.txt, available at > the usual places (e.g., > http://www.ietf.org/internet-drafts/draft-ietf-tcpm-tcp-uto-03.txt). > > Feedback is more than welcome. ;-) > > Kindest regards, > > -- > Fernando Gont > e-mail: fernando@gont.com.ar || fgont@acm.org > PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1 > > > > > > > _______________________________________________ > tcpm mailing list > tcpm@ietf.org > https://www1.ietf.org/mailman/listinfo/tcpm
_______________________________________________ tcpm mailing list tcpm@ietf.org https://www1.ietf.org/mailman/listinfo/tcpm
- [tcpm] TCP zero window timeout? Mahesh Jethanandani
- RE: [tcpm] TCP zero window timeout? Mahdavi, Jamshid
- RE: [tcpm] TCP zero window timeout? Fernando Gont
- Re: [tcpm] TCP zero window timeout? Mahesh Jethanandani
- Re: [tcpm] TCP zero window timeout? Joe Touch
- Re: [tcpm] TCP zero window timeout? Fernando Gont
- Re: [tcpm] TCP zero window timeout? MURALI BASHYAM
- RE: [tcpm] TCP zero window timeout? Anantha Ramaiah (ananth)
- Re: [tcpm] TCP zero window timeout? Joe Touch
- Re: [tcpm] TCP zero window timeout? Kuthonuzo Luruo (STSD)
- Re: [tcpm] TCP zero window timeout? Ted Faber
- Re: [tcpm] TCP zero window timeout? Fernando Gont
- Re: [tcpm] TCP zero window timeout? MURALI BASHYAM
- Re: [tcpm] TCP zero window timeout? MURALI BASHYAM
- Re: [tcpm] TCP zero window timeout? Mahesh Jethanandani
- RE: [tcpm] TCP zero window timeout? Caitlin Bestler
- RE: [tcpm] TCP zero window timeout? MURALI BASHYAM
- Re: [tcpm] TCP zero window timeout? Fernando Gont
- Re: [tcpm] TCP zero window timeout? Ted Faber
- Re: [tcpm] TCP zero window timeout? MURALI BASHYAM
- RE: [tcpm] TCP zero window timeout? Caitlin Bestler
- Re: [tcpm] TCP zero window timeout? John Heffner
- RE: [tcpm] TCP zero window timeout? MURALI BASHYAM
- RE: [tcpm] TCP zero window timeout? Caitlin Bestler
- Re: [tcpm] TCP zero window timeout? Mahesh Jethanandani
- Re: [tcpm] TCP zero window timeout? Joe Touch
- Re: [tcpm] TCP zero window timeout? Ted Faber
- Re: [tcpm] TCP zero window timeout? Joe Touch
- Re: [tcpm] TCP zero window timeout? Ted Faber
- Re: [tcpm] TCP zero window timeout? Joe Touch
- Re: [tcpm] TCP zero window timeout? Ted Faber
- Re: [tcpm] TCP zero window timeout? Ted Faber