Hello, More and more groups are using network descriptions, and want to identify specific resources, e.g. a specific node, link, or instance of a (light)path. Defining an instance identifier format is also in scope of the NML-WG. Yesterday we discussed this in the meeting, with several proposals (see the slides on GridForge). In the end in the meeting there was consensus on using the following: urn:ogf:network:<dns name>:<opaque part> So for example: "urn:ogf:network:example.net:xyz123". The opaque part of the identifier is determined by the originating domain, and it should be completely opaque. Other domains should not interpret that part, other than seeing it as a unique identifier for a resource. This makes it possible to define equality as a simple string comparison between identifiers. If you have any questions or comments on this proposal, please let us know. Regards, Jeroen.