Re: [OPSEC] review draft-gont-opsec-icmp-ingress-filtering-02

Mikael Abrahamsson <swmike@swm.pp.se> Wed, 17 August 2016 06:56 UTC

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Date: Wed, 17 Aug 2016 08:55:59 +0200
From: Mikael Abrahamsson <swmike@swm.pp.se>
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Subject: Re: [OPSEC] review draft-gont-opsec-icmp-ingress-filtering-02
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On Fri, 15 Jul 2016, joel jaeggli wrote:

> I'm sympathic generally to this draft, section 5 implementation details 
> could be rewriten more cleanly to suggest how it is implemented. e.g.

I also read this document. I am also sympathetic to this draft, but I 
tried to find what kind of attacks can be performed using the technique 
mentioned in the document, but apart from the US-CERT reference from 2005, 
I came up empty.

I would like to see more references to documents describing what can 
happen if the proposed mechanism isn't implemented, ie list of attack 
vectors.

Apart from that I like the document. I have doubts about how widely this 
mechanism will actually get implemented since it's like uRPF; it doesn't 
protect the implementor from the Internet, it protects the Internet from 
the implementors' customers.

But it makes a lot of sense to document this problem and recommend that 
this kind of filtering is done.

-- 
Mikael Abrahamsson    email: swmike@swm.pp.se