[rrg] [lisp] Please respond: Questions from the IESG as to whether a WG forming BOF is necessary for LISP

[Joel M. Halpern]

I don't think those are the only two alternatives.  For example, 
something like the APT idea where the full mappings are shipped to a set 
of devices such that such a full set is near to and on the query path of 
any leaf is an alternative worth examining.

 From a design perspective therefore, I would tend to look for a system 
where a device can be sent unsolicited mappings, can choose to keep 
them, and can issue a query via an overlay to resolve mappings it does 
not have.
While one could argue that this complicates the protocol, it is an 
unneeded complication only if we are very sure we know what the right 
answer is for information distribution.  It is admittedly more complex 
than just using BGP to carry EIDs.  Are we sufficiently sure?

It then becomes an operational decision whether the mappings are in any 
given leaf, in some intermediate devices, or in just the originating 
leaves.  (While the decision on the alternatives can not be made wholly 
independently by all the branches of the overlay tree, there is room for 
flexibility.)


Yours,
Joel

Dino Farinacci wrote:
>> Dino -
...
> The point here is begging a single question:
> 
>     1) Should all the mappings in the universe be in an ITR?
> 
>     2) Should only the mappings for sites the ITR is currently talking 
> to be in the ITR?
> 
> This is the important matter. Decide on that then we can talk about how 
> to get the mappings where they need to be.
>