Hi Tom,

In the thread "Re: [rrg] Pumping IRON" you wrote, quoting Tony Li,
you wrote:

>> Note that it is the responsibility of the shepherd to get the document to
>> the state where the RG gives consensus that it should be published.  This
>> applies to all of the documents that we have started, not just Fred's.
>>
>> I'm concerned as I've seen no action from shepherds or membership on any of
>> the proposal-specific documents.
> 
> Robin
> 
> I would urge you to progress some of your ideas towards RFC, especially the 
> one
> on CEE-CES split that you have explored on this list several times.

Thank for your interest in this.  I agree it would be good to
document this in an RFC.

A very short version of the distinction is at the end of section
17.3.3 of:

  http://www.ietf.org/mail-archive/web/rrg/current/msg06219.html

and is quoted below.  In greater detail:

  http://www.ietf.org/mail-archive/web/rrg/current/msg06250.html
  http://www.ietf.org/mail-archive/web/rrg/current/msg05865.html

CEE (Core Edge Elimination) involves hosts doing more work than at
present, which requires more packets, longer packets and frequently
extra delays establishing initial communications.  CES (Core Edge
Separation) involves no changes to host protocols.  The work is done
by new elements in the network, such as "Ingress Tunnel Routers",
"Egress Tunnel Routers" and various mapping servers.  I believe it is
possible to do CES with initial communications delays which are
generally minimal enough not to be a concern to anyone.


> I think that that idea is an important contribution to routing architectures 
> and
> may well be significant when most of what we have discussed here has been
> forgotten.  

OK - its not my idea, but I tried to document it clearly and resolve
some problems I perceived in the terminology.

I can't imagine ILNP or LISP being widely adopted and so I guess the
whole question of scalable routing, mobility etc. will be revisited
in five or ten years.  Then, the CEE/CES distinction and some
approaches which are currently not widely favoured will be of
interest.  (Alternatively someone will develop a commercial service
based on TTR Mobility and DRTM - and IETF standards will have to
catch up.)

I assume the RRG archives will remain as they are, in perpetuity.  My
Ivip pages are there for keeps and archive.org will eventually catch
up with the current contents.  archive.org doesn't cover the RRG
archives.


> One caveat; I think that any such RFC would need to make sense to
> those who have never heard of hIPv4, NOL, RANGI, NMS, TIDR, EEMDP etc.  We who
> have followed this list have a knowledge that noone else will ever acquire and
> so any I-D that depends on that knowledge will generally be unintelligible.

I agree.  I think the messages mentioned above achieve this.
However, they tend to assume a particular understanding of the
problem and goals - something the RRG has never agreed on.  To see my
attempt at describing the problem/goals, please see section 17.2 of:

  http://www.ietf.org/mail-archive/web/rrg/current/msg06219.html


> Rather, I would like to see CEE-CES presented in the more commonplace concepts
> of address, headers, tunnels etc, perhaps with reference to the specific
> instantiations discussed here as appendices, as opposed to starting off by
> saying 'these are CES, those are CEE', which will lose most of the audience:-(

In 2015, 2020 time-frame, I agree.  For RRG readers, I think it makes
sense to list the various proposals first.  From msg06219, here is
the very short version, which doesn't refer to any particular
architectures:

= = =

   CEE   Core-Edge (address) Elimination:  A class of scalable
         routing architectures in which the Locator / Identity
         Separation naming model is introduced, replacing the
         current IPv4/v6 model in which the IP address plays both
         the Identifier and Locator roles.

         Hosts have portability of Identifiers and are able to do
         multihoming and inbound TE on IP addresses derived from
         two or more PA prefixes from two or more ISPs.  These
         addresses are conventional PA "core" addresses and each such
         PA prefixes for an end-user network is fully aggregated into
         a shorter prefix the ISP advertises.  Therefore, this use of
         address space is regarded as scalable.  (This doubling or
         more of each end-user network's address requirements is one
         of the reasons CEE architectures are impractical for IPv4.)*

         Therefore there is no need for any "edge" addresses - the
         unscalable PI addresses which are currently the only way of
         achieving portability, multihoming and inbound TE.

         A fully adopted CEE architecture therefore eliminates the
         need for "edge" addresses, and so for the distinction
         between "core" and "edge" addresses.

         The full sense of "Elimination" in this term is "Elimination
         of the need to distinguish between core and edge addresses,
         since there is no longer a need for edge addresses."


   CES   Core-Edge (address) Separation: a subset of the global
         unicast address space is separated from the remaining
         "core" global unicast addresses and is supported by the
         CES system (ITRs, mapping system and ETRs) to be used as
         a new form of address space by which end-user networks
         can obtain the benefits of Portability, Multihoming and
         inbound TE in a scalable manner.  This space is used in a
         manner which involves far less impact on the DFZ control
         plane per end-user prefix than than current PI techniques.

         The full sense of "Separation" in this term is "Separation
         of the global unicast address space into a scalable 'edge'
         subset, with the remainder being 'core' addresses".  Since
         Portability, Multihoming and inbound TE can be provided
         with this new scalable "edge" space, there is no longer
         any need for the unscalable PI edge space.

= = =

* Since I wrote this, ILNP for IPv4 has been proposed, with a new,
  longer, header to accommodate a separate Identifier, and use full
  IPv4 addresses as Locators.  This doesn't have the same attraction
  (architectural "cleanliness" or "elegance") as ILNP for IPv6,
  because it requires upgrades to DFZ and other routers, longer
  packets to hosts etc.



> The other idea of yours that I think will be of long term benefit is real time
> mapping.  It does set your ideas apart from the others, and if and when the
> others find they need it too, then having a well-documented scheme will prove 
> a
> valuable starting point.

OK - thanks for your interest in this.  The documentation at present
should be read in this order:

  1 -  http://www.firstpr.com.au/ip/ivip/drtm/   (Color diagrams.)

  2 -  http://tools.ietf.org/html/draft-whittle-ivip-drtm

  3 -  http://www.ietf.org/mail-archive/web/rrg/current/msg06128.html
       (Please read only the section on "DNS-based system so TRs can
        find DITR-Site-QSDs.)


Unfortunately, in the foreseeable future, I don't have time to work
on any of this, including writing RFCs.  I worked pretty much
full-time on RRG things, analysing all the proposals and developing
DRTM, in the first 3 months of this year.  Now I need to catch up on
paying work.

If anyone else wants to work on an RFC on these, I would be greatly
encouraged and will do my best to help.

  - Robin

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