Re: failure detection

[Iljitsch van Beijnum <iljitsch@muada.com>]

On 29-aug-2005, at 15:52, marcelo bagnulo braun wrote:

> > So I think that if we are going to add an indication that a prefix  
> > isn't working, so that shim6 hosts can change the locator they use  
> > more quickly,

> agree, but i was thinking also about non-shim hosts  (sorry for not  
> stating) this before) (i.e. unmodified hosts) and whether it would  
> be possible to enable routers to detect that the link with a given  
> ISP is down and inform hosts within the multihomed host not to use  
> it anymore (especially in order to avoid trying with prefixes that  
> we know are down for establishing new communications and reducing  
> latency at establishment)

I think it would be entirely appropriate to deprecate prefixes tied  
to the impaired ISP.

This is also something that can actually happen quite fast: routers  
can just send out an RA with the prefix' preferred lifetime set to 0  
and the hosts will deprecate their addresses immediately. (Doing the  
same for the valid lifetime won't work as there is a minimum of two  
hours for security reasons.)