Re: [shim6] Problems with ULID (IP) over longer sessions.

Erik Nordmark <> Mon, 03 May 2010 16:20 UTC

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Date: Mon, 03 May 2010 09:19:29 -0700
From: Erik Nordmark <>
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To: Javier Ubillos <>
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Subject: Re: [shim6] Problems with ULID (IP) over longer sessions.
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On 05/ 3/10 03:06 AM, Javier Ubillos wrote:

> It looks as if 1.5 was what I was unknowingly referring to.
> However, if not when the locator becomes unreachable, when is an ULID
> declared invalid?

I think you are asking about the definition of "invalid", which is 
specified in RFC 4862. (It is when the address allocation is withdrawn, 
whether using stateless address allocation or DHCPv6.) In an 
implementation that typically corresponds to the address no longer being 
configured e.g., doesn't show up in ifconfig -a.

This is completely unrelated to an address being unreachable.

Note that the address allocation needs to be withdrawn before the 
address can possibly be reassigned to some other node.

> When that locator _does_ respond, but with invalid context (or some
> other expected 'error' behavior)?
> When it becomes un-routable? (prefix change)

I don't know what an "invalid context" means. Please explain.

A shim6 host can loose state, which can result in one end having context 
state and the other end not having it. RFC 5533 specifies how the 
protocol recovers from context state loss.