[ih] Why did location/identity separation not happen? (Was: Internet without entrenched factions?)

[Greg Skinner]

Comments inline

On May 17, 2026, at 4:02 AM, Noel Chiappa via Internet-history <internet-history at elists.isoc.org> wrote:
> 
>> From: Ole Troan
> 
>> Back to history. IPv6 should have had identifier/locator split from the
>> start. I wasn't there, but I understood it was close with Mike O'Dell's
>> 8+8 and GSE proposals? Anyone who can shed more light on what happened
>> and why that path was not chosen?
> 
> I wasn't paying very close attention by then, so I don't know for sure why
> 8+8/GSE didn't get support, but I would guess that it was for many of the
> same reasons that earlier attempts to add location/identity separation to the
> internetworking architecture (i.e. the 'basic, high-level picture', used in
> the Internet) failed to catch on.
> 
> Those, I believe, I am very well qualified to muse about, since I'm pretty
> certain (if my memory is failling me in this, which might well be possible, I
> hope someone will correct me) was the first person in the Internet technical
> community (which was, at the time, pretty well entirely encompassed in the
> IETF/IRTF groups) to suggest, and push, adding separation of location and
> identity to that architecture.
> 
> (The basic idea, of course, originated with Jerry Saltzer, in his paper "On
> the Naming and Binding of Network Destinations". As soon as I saw it, I
> realized the crucial flaw in the then-current internet architecture which it
> pointed out, and took steps to get it re-published as an RFC - RFC 1498 - to
> make it easily accessible to the Internet technical community; it had
> originally been published in a somewhat obscure journal. I can't remember if
> Jerry provided me with a machine-readable copy of the text, for that; I have
> a vague memory that that had been lost, and I had to re-type it all from a
> hard copy.
> 

I found a Local Network Note that is very similar to RFC 1498 that is dated 3 March 1981. [1] (More on this later.)

> Also, the version of the idea that I pushed had one major change from Jerry's
> original: he had proposed recognizing four classes of entities - "services,
> nodes, attachment points, and routes [i.e. paths]". Dave Oran suggested to me
> (in a conversation at a meeting in LA, if memory serves - the memory is still
> fairly vivid) that physical hosts were the wrong thing, it needed to be
> something more abstract, and I instantly saw the correctness of his point.
> 
> I drew on Clark's original "fate-sharing" thinking, used in the early TCP
> work, to replace 'node/host' with 'endpoint' - defined as "a fatesharing
> region" ("a boundary drawn around a set of state and/or computations such
> that it lives or dies as a unit"), which is "one participant of an end-end
> communication" ("the fundamental agent [in] end-end communication"). Excerpts
> here are from:
> 
>  http://chiappa.net/~jnc/tech/endpoints.txt

> "Endpoints and Endpoint Names: A Proposed Enhancement to the Internet
> Architecture". )
> 

I had to go to the Internet Archive to access this paper. [2]

> Anyway: what, from my perception, were the reason(s) that separation of
> location and identity failed to catch on in the Internet technical community?
> It can, I believe, be put, whimsically but pithily, as 'there were too many
> programmers in that technical community'. (This may irritate people; I don't
> care, I'll be gone before too long. I don't say it to irritate _anyone_, but
> because I believe it is accurate.)

> Whhaaatttt? […]

> To less whimsically explain what I said at the start , I think the vast
> majority of the members of the IETF technical community could only see the
> value in a significantly new direction if they had seen it fully constituted,
> in a working system. 

IMO,  this is not unreasonable, especially if those programmers answer to managers who have to deal with practical constraints, such as budgets.

Anyway, back to RFC 1498, since these issues were known at the time the TCP and IP IENs that preceded their corresponding RFCs were written, what did other people in Saltzer’s group think about this?  For that matter, what did DCA think about this?  Were they ever approached with any of these concerns, such as how much more difficult mobility, etc. would be without location/identity separation?

Finally, it seems to me that the LISP project has taken this up. [3] Is that not sufficient?  They seem to have support from industry, working code, use cases, etc.  Maybe it’ll be more widely adopted.

--gregbo

[1] https://web.mit.edu/~saltzer/www/publications/lnn/csr-lnn-028.pdf
[2] https://web.archive.org/web/20070112102344/http://ana.lcs.mit.edu/~jnc/tech/endpoints.txt
[3] https://www.lispers.net