RE: [xri] XRI Names and XRI Addresses

["Drummond Reed" <drummond.reed@onename.com>]

>>Drummond Reed wrote:
>>
>>
>>My one suggestion after chewing on this over the weekend is that we
>>might want to use the modifier "persistent" when talking about XRI
>>addresses because that is what so significantly distinguishes them
from
>>IP addresses (or any form of name, whether a DNS name or an XRI name).
>>So from an Internet resolution standpoint the four possible layers
would
>>be:
>>
>>* XRI name
>>* XRI persistent address
>>* DNS name
>>* IP address
>>
>>You can skip a layer any time a resource doesn't need the features of
>>that layer, i.e., an XRI name can refer directly to a URI or an IP
>>address if the resource does not need a persistent identifier, or an
XRI
>>persistent address can refer directly to an IP address if it doesn't
>>need a DNS name.
>> 
>>
>Peter Davis wrote:
>
>I have concerns with layering "persistent" or more clearly
>"non-reassignable" [1] addresses over the DNS, which IS re-assignable
>(as are IP addresses for that matter).perhaps your intent was
>informative rather than "normative" ;-)  at any rate, while the analogy
>with the DNS and IP addressing is usfull in an informative sense, I'd
>suggest we avoid discussing reassignable layers under persitant ones.
>
>Or did i simply miss your point?
>
>--- peterd
>
>
>[1]
>http://www.oasis-open.org/apps/org/workgroup/xri/email/archives/200305/
msg00013.html

I think maybe it's just a misunderstanding about the meaning of
"persistence". A URN establishes a persistent identifier for a resource
- one that will never be reassigned to another resource (unlike, as you
point out, a DNS name, an IP address, or an XRI name for that matter,
all of which may be reassigned to another resource). However, as
discussed in the new Motivations section of the Requirements doc, URNs
systems are designed to be layered over reassignable addresses such as
DNS names or IP addresses because the abstract, persistent URN address
must be mapped, at a certain point in time, to a concrete, reassignable
address such as a DNS- or IP-based URI.

So as the resource moves around on the network, the underlying URI that
a URN resolves to may change, but the URN stays the same.

=Drummond