Re: [v6ops] Extension Headers / Impact on Security Devices

Fernando Gont <fgont@si6networks.com> Tue, 19 May 2015 07:15 UTC

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Date: Tue, 19 May 2015 01:15:54 -0300
From: Fernando Gont <fgont@si6networks.com>
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To: Mark ZZZ Smith <markzzzsmith@yahoo.com.au>, Enno Rey <erey@ernw.de>, "v6ops@ietf.org" <v6ops@ietf.org>
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Subject: Re: [v6ops] Extension Headers / Impact on Security Devices
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On 05/15/2015 10:22 PM, Mark ZZZ Smith wrote:
> So quickly, how have IPv4 options been handled? They too can vary the
> location of the TCP/UDP etc. headers in an IPv4 packet. How have the
> variety and variable number of TCP options been handled? They too can
> vary the location of the TCP segment payload.

There are substantial differences here:

* The size of IPv4 options is very limited (well under 128 bytes)

* IYou only need to look at the IHL of the IPv4 packet to be able to
jump to the layer-4 protocol header. -- there's no such a thing in IPv6.

Thanks,
-- 
Fernando Gont
SI6 Networks
e-mail: fgont@si6networks.com
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