Re: [tcpm] TCP zero window timeout?
Mahesh Jethanandani <mahesh@cisco.com> Tue, 29 August 2006 21:29 UTC
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Date: Tue, 29 Aug 2006 14:29:00 -0700
From: Mahesh Jethanandani <mahesh@cisco.com>
Organization: Cisco Systems Inc.
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To: Caitlin Bestler <caitlinb@broadcom.com>
Subject: Re: [tcpm] TCP zero window timeout?
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Cc: tcpm@ietf.org, Ted Faber <faber@ISI.EDU>, "Anantha Ramaiah (ananth)" <ananth@cisco.com>, "Mahdavi, Jamshid" <jamshid.mahdavi@bluecoat.com>, Fernando Gont <fernando@gont.com.ar>
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Caitlin Bestler wrote: >>Are u suggesting that the application query TCP to determine >>that the connection is stuck in persist state and how much of >>the data has been sent or not and so on? That sounds a little >>roundabout and complicated... >> >> > >And/or the application convey an application specific tolerance >for such a state through a local interface. > > We agree that application can help TCP by suggesting how tolerant it wants to be. >If the behavior can be corrected through a local interface, >and there is no IETF language barring or discouraging such >an interface, then why is this something that TCPM should >consider? > > Information of how long the connection has been stuck in persist state, how many retry probes have been made and whether each of them has resulted in a zero window is all in TCP. So TCP(m) has to be involved. Who actually issues the reset on the connection is a implementation level detail which we can get into once we agree that we have a DOS situation. >The nature of the Denial of Service attack presented does >not seem to require real-time defenses and definitely does >not present a strong case for any network element modifying >their "fast path" handling of packets. > If we accept that it is a DOS attack, then the problem needs to be addressed. Our suggestion only says that today's behavior of infinite TCP probes in persist state lends itself open to a DOS and so the probes should have the option to be capped with a timeout.
_______________________________________________ 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