Re: OSPF WG Minutes

Vishwas Manral <Vishwas@SINETT.COM> Tue, 16 August 2005 04:33 UTC

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Date: Mon, 15 Aug 2005 21:34:42 -0700
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From: Vishwas Manral <Vishwas@SINETT.COM>
Subject: Re: OSPF WG Minutes
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Hi Acee,

> Acee: In practice, for OSPFv2 the sequence numbers are not monotically
> increasing; Usage of router's clock for cryptographic sequence number 
> generation reduces the chance for replay attacks across restarts. 
> ?: OSPF spec does not say it ...
Acee, what I meant was that although the OSPF spec does not state that
we need to use clocks. 

I think the vulnerabilities draft is the right place to state the
problems that can happen if we do not use a clock (or something
equivalent which increments even when a system goes down).

Another issue is that even if the sender uses clock for the "sequence
number" and goes down, all the packets of a previous session can still
be replayed by another router. So the chance of replay attacks is still

-----Original Message-----
From: Mailing List [mailto:OSPF@PEACH.EASE.LSOFT.COM] On Behalf Of Acee
Sent: Monday, August 15, 2005 7:50 PM
Subject: OSPF WG Minutes

Attached are the minutes from the Paris OSPF WG meeting. Thanks to
Dimitri for taking them.