Things had gotten a bit quiet so I figure I should open up a can of worms :-) . Freek Dijkstra wrote:
In short: name MUST NOT be context-sensitive. I think it is bad if I can only describe an interface as "eth0 of host3 in network 8". I much rather say interface "intf639" and only if required tell that it is in "host3" and that "host3" is in "network8".
Of course, this requires that names are globally unique. I prefer to use opaque names (any string, without syntax requirements), as long as it is unique. URIs come to mind.
If we mandate that *all* naming is completely context independent, then when given a random identifier, users are completely at a loss (since no context implies no domain information) as to where to get information on an element. If the only context it has is "this domain contains [uuid]", our schema can work like that except it adds a bit of extra information on it so you can type-check a given id. For example, if you didn't want any hierarchy below domain, you could just label everything like: urn:ogf:network:domain=Internet2.edu:node=node1345 urn:ogf:network:domain=Internet2.edu:port=intf639 urn:ogf:network:domain=Internet2.edu:link=link23 By defining an allowed hierarchy, we allow administrators to construct context dependent elements if they want, and when they do, we know what the structure means. It also makes it truly trivial to generate unique identifiers that retain some meaning. When discussing a specific port, "urn:ogf:network:domain=Internet2:port=intf639" is not as readable as "urn:ogf:network:domain=Internet2:node=packrat:port=eth0". The latter may be longer, but it's significantly more readable and has the added benefit of allowing you to summarize a list of interfaces on packrat as "urn:ogf:network:domain=Internet2:node=packrat:port=*" which would be impossible without the hierarchy. I'm not saying that we should prevent administrators from having elements named in a context-independent way inside of domains, just that we should allow the option of context-dependent ids in a way that other domains can understand. Cheers, Aaron