RE: review of draft-ietf-shim6-failure-detection-03.txt

[<john.loughney@nokia.com>]

Marcelo,

>> I think we should drop the '... may be used in other contexts.' as 
>> this seems outside of the scope of SHIM6. I don't think that SHIM6 
>> should work on a general purpose failure detection & path exploration

>> protocol.
>
>I think that there are several scenarios where there seems to be the 
>need for having a protocol for detecting failures and exploring 
>alternative paths. For instance, in mobile IP, there is no way to 
>determine if the current CoA is working and explore alternative coas if

>a failure is detected. Similar thing happens in HIP for instance.
>
>So, my take on this is that perhaps it would be good if the failure 
>detection and alternative path exploration protocols defined by shim6 
>could be reused in such scenarios (of course if this does not implies 
>giving up functionality, but i don't think this is the case)
>
>I mean, if we can define a single protocol that can be used in multiple

>scenarios that need the same functionality i think it makes sense....

It makes sense, but the devil's in the details.  Many (most?) protocols
running over IP or UDP have some failure detection mechanism - usually 
by using of keep-alives.  I'm not sure if SHIM6 is the place to do this
general purpose failure detection & path exploration protocol; perhaps
the chairs can comment.

Anyhow, I imagine that SHIM6, MobIKE, HIP, etc. might have slightly
different
needs or requirements for this kind of functionality and how do we
ensure
that we don't over-engineer a solution but make sure it covers the needs
of protocols outside of SHIM6.

John