Quoting RFC2860 [Re: I-D Action:draft-azinger-scalable-addressing-00.txt]

[Tony Li]

Hi Michael,

> I think I see where I am missing a point of the draft here.  Consider the example of a small ISP that provides v4/v6 dial-up services (and maybe even runs a v6 tunnel broker) for rural customers.  They are single-homed.  From a topological perspective, they look exactly like an end site, despite the fact that they provide services to a lot of independent customers.  OTOH, a large corporation that has several campuses and is multi-homed definitely looks like a service provider topologically, even though it is only providing services to itself.
> 
> For me, who sometimes looks at these things economically, the former is a service provider and the latter is an end site.  Topologically, the former is an end site and the latter is a service provider.


Thank you, that's an excellent way of describing the differences.


> Would it clarify things to recommend that single-homed entities get PA and multi-homed get PI rather than use the more loaded distinction between service providers and end sites, or is that not the intent of the draft?


This almost works for me.  Instead I would say that single-homed entities get PA and mildly multi-homed get PA and grossly multi-homed get PI.

The difference is simply one of numbers: if mildly multi-homed entities get PI and there are a plethora of them, then we have not resolved the scalability issue.

Tony