Re: sockets APIs extensions for Host Identity Protocol

[Keith Moore <[e-mail]>]

> My exact question is that what to put into the socket address
> structures when we have HIP-aware applications. Based on the
> discussion, I think we can leave socket address structures based on
> DNS names out of the scope and concentrate on two alternatives:
> globally scoped HITs and locally scoped idenfiers (endpoint descriptors).
>
> The use of globally-scoped HITs has the following trade-offs:
> + No extra translation step from local id to global id
> + Smaller transition step to convert a legacy app to a HIP aware app?
> - Opportunistic HIP mode, where the server's HIT is not known before
> hand,
>   will require a locally-scoped identifier anyway. This is similar to
>   IN6ADDR_ANY, but it is used for the remote host, i.e.,
>   connect(UNKOWN_HIT) where only the locator is known.
> - No future proofing against the HIT size
>
> Locally-scoped identifiers have the reverse properties:
> - Extra translation step from local id to global id
> - Bigger transition step to convert a legacy app to a HIP aware app?
> + All identifiers are of the same type (also in opportunistic HIP mode)
> + Future proofing against changes in the HIT size
>
> If you had to choose between these two, what would you choose and why?
> Do the proposed trade-offs make sense and would have something to add?
offhand, I think you need to support both.  HITs aren't very useful to
apps unless they are visible to them and globally-scoped.  HIP is still
useful without HIT visibility, but less useful.