Joel,

Yes, thank you - that is a better phrasing.

Alia

On Thu, Jun 23, 2011 at 3:37 PM, Joel M. Halpern <[email protected]> wrote:
> I don't think your paraphrase quite captures it.
> In the abstract theory, the bit string represented by A could be an EID for
> one device and an RLOC for a different device.
> As the architecture is realized, if a given bit string is both an RLOC and
> an EID, it must refer to the same entity in both cases.
>
> Yours,
> Joel
>
> On 6/23/2011 2:43 PM, Alia Atlas wrote:
>>
>> So - although theoretically the value A can be an EID and an RLOC, the
>> LISP
>> protocol as specified does not permit this.
>>
>> I understand that was a choice started based upon assumptions around the
>> allocation authority for number spaces.
>>
>> I strongly think that this clarification must be made in the [LISP]
>> draft.  Without
>> that assumption, various parts of what is specified simply do not work.
>>
>> Alia
>>
>> On Wed, Jun 22, 2011 at 7:02 PM, Dino Farinacci<[email protected]>  wrote:
>>>>
>>>>  From the discussion on draft comments, I have the following basic
>>>> question:
>>>>
>>>> Is a value A is assigned to either the EID space or the RLOC space?
>>>> Could site X have an EID with value A while site Y (or
>>>> even a non-LISP) has an RLOC (or globally routable address) with the
>>>> same value A?
>>>
>>> Architecturally, yes, the value A can be an EID and an RLOC. In practice,
>>> no, for IPv4 and maybe for IPv6. Let me explain.
>>>
>>> Since there are two namespaces for each of IPv4 and IPv6, it means, for
>>> the
>>> case of IPv4, there are two 2^^32 number assignment spaces. But we don't
>>> have two allocation authorities, one for each, so the addresses will be
>>> assigned from one 2^^32 pool and be used as either an EID or an RLOC
>>> depending if the site has converted to being a LISP site.
>>>
>>> For IPv6, if we had a PI allocation authority, then it would hand out EID
>>> prefixes to end sites. If we also had a PA allocation authority, then it
>>> would hand out RLOC addresses to infrastructure providers. In this case,
>>> if
>>> the two authorities acted independently, then the same value could be
>>> assigned for each namespace.
>>>
>>> This is not a problem to duplicate the address in each namespace. But I
>>> do
>>> believe for operational sanity it would be nice to look at logs, debugs,
>>> or
>>> whatever, see an address and decipher it is an EID versus an RLOC. This
>>> is
>>> one of the reasons the working group wants to request an IANA assigned
>>> /12
>>> or /16 (not decided yet I think).
>>>
>>>> For instance, consider deploying an IPv4 LISP site now.  Could one
>>>> take an IPv4 prefix already used
>>>> globally by a different company/site - and use it for my new LISP site
>>>> as an EID prefix?
>>>
>>> No because there is one allocation authority and it is enforcing a unique
>>> address allocation policy.
>>>
>>>> Do all the drafts always check for the IP address in the mapping
>>>> database to see if it is an EID?  I recall seeing some
>>>> cases of checking the global routing table - but that could be bad
>>>> memory at this point.
>>>
>>> If you look in the ALT routing table and find a prefix, it is an EID.
>>> That
>>> is an example of looking in *a routing table*. But that is part of the
>>> mapping database system. So it is one in the same.
>>>
>>>> Could a host in a LISP site send to an IP address as an EID and the
>>>> same IP address as a globally addressable (or routable)?
>>>
>>> A host sends to destinations. So it doesn't know one from the other (a
>>> feature). So yes, both a non-LISP site host and a LISP site host can talk
>>> to
>>> both a non-LISP site and LISP site destination.
>>>
>>>> I am confused because "architecturally" I believe the EID space and
>>>> the RLOC space are separate namespaces - but in practice
>>>> in the drafts, it seems that a given value must belong to a single
>>>> entity, whether it is used as an EID, globally addressable, or both.
>>>
>>> That is what you get when you build an architecture after the network is
>>> built.  ;-)
>>>
>>> Dino
>>>
>>>> Is this clearly specified anywhere?  What am I missing?
>>>>
>>>> Alia
>>>> _______________________________________________
>>>> lisp mailing list
>>>> [email protected]
>>>> https://www.ietf.org/mailman/listinfo/lisp
>>>
>>>
>> _______________________________________________
>> lisp mailing list
>> [email protected]
>> https://www.ietf.org/mailman/listinfo/lisp
>>
>
_______________________________________________
lisp mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/lisp

Reply via email to