Re: [v6ops] [EXTERNAL] Improving ND security

Fernando Gont <> Fri, 31 July 2020 19:43 UTC

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To: "Bjoern A. Zeeb" <>, v6ops list <>
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From: Fernando Gont <>
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Date: Fri, 31 Jul 2020 16:30:15 -0300
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Subject: Re: [v6ops] [EXTERNAL] Improving ND security
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On 31/7/20 16:03, Bjoern A. Zeeb wrote:
>> SEND seems to me like a nice idea, but overly complex for the problem 
>> it's trying to address.
> It is these unbacked statements which people will use to reason against it.
> “complex” is not a cause unless it is backed by proper arguments.
> “trust distribution” is a thing, which doesn’t really work in a coffee 
> shop around the corner.

SEND implies the use of a PKI. That's non-trivial.

Besides, the expectations for IPv6 are similar to those for IPv4. 
Somehow folks have been able to secure the ipv4 first-hop (when/where 
needed) without the need of understanding something like SEND, or going 
through the hassle of deploying it. So the question "Why do I need this 
for IPv6 when I never required it for IPv4?" may not an easy one to respond.

> I have no idea how the support for major OSes and router vendors is a 
> decade later, but I’d be curious if someone would do a proper survey and 
> post the results.  I think that would be super helpful (not as an RFC, 
> but as a “state snapshot”);  could be a blog post or a cloud based 
> spreadsheet somewhere.

I don't seem to remember any major OS that ships with SEND enabled by 
default -- e.g., that configures CGAs over traditional SLAAC or RFC7217.

Additionally (and ironically), the use of IPv6 EHs tends to be rather 
unfriendly to first-hop security.

> [2] 
>   (I hope the link is good, I cannot currently reach their site)

The link is good. However, it claims "Download: Not available for public 

Fernando Gont
SI6 Networks
PGP Fingerprint: 6666 31C6 D484 63B2 8FB1 E3C4 AE25 0D55 1D4E 7492