On May 10, 2012, at 7:41 AM, Freek Dijkstra wrote:
I've just created a new artifact, https://forge.ogf.org/sf/go/artf6507
Here is the full proposal.
Adaptation is between Ports, and requires the following objects: * 2 Link instances * 4 Port instances * 2 Adaptation instances * 8 relations between these instances (see https://forge.ogf.org/sf/go/artf6514 for details)
While the above is great to describe a topology in detail, it is sometimes useful to describe less detail.
I propose a shortcut to define adaptation between Links: Link --(providesLink)--> Link
This would only require the following objects: * 2 Link instances * 1 relation between these instances
This is similar how isSerialCompoundLink also relates Link objects, bypassing the more tedious Link <--(isSink)-- Port --(isSource)--> Link relations.
Of course this is less detailed (e.g. it is not possible to describe the type or adaptation, or the name of the Ports). It's intended use is a situations where a full topology description (with all ports) is not required or not desirable.
NML:
Link --(providesLink)--> Link
The subject (Link on the left) is on the server layer. The link of the right (the object) is one the client layer, and source and sinks of both Links MUST be related with an equal adaptation stack. In other words, both Links MUST span the same distance.
For example, in the following ASCII-art, the following statements are True: l0 --(providesLink)--> l1 - True l0 --(providesLink)--> l2-2 - True l1 --(providesLink)--> l2-2 - True While the following statements are all False: l0 --(providesLink)--> l3 - False l1 --(providesLink)--> l3 - False l2-2 --(providesLink)--> l3 - False
l3 O -----------------------------------------------> O | | _ _ V V | l2-1 l2-2 l2-3 | O -------------> O -------------> O -------------> O | | _ _ V V | l1 | O -------------> O | | _ _ V V | l0 | O -------------> O
From these requirements follows that the subject is always a terminated network connection (thus not a segment of a larger link connections), while the object is never a serial compound link.
XML example:
<nml:Link id="urn:ogf:network:example.net:2012:link:fiber:NOR:xe-1-1-0:AMS:xe-2-1-0:1530nm"> <nml:name>1530nm wave between NOR and AMS</nml:name> <nml:Relation type="providesLink"> <nml:Port idRef="urn:ogf:network:example.net:2012:link:eth:NOR-AMS-0001" />
Should this be <nml:Link> and not <nml:Port> ? If not, I'm apparently missing something obvious. If so, I'm fine with the proposal. Cheers, Aaron
</nml:Relation> </nml:Service>
RDF example:
@prefix nml: <http://example.ogf.org/schemas/nml/>; . @prefix nmlrel: <http://example.ogf.org/schemas/nml-relation/>; . @prefix ex: <urn:ogf:network:example.net:2012> .
ex:link:fiber:NOR:xe-1-1-0:AMS:xe-2-1-0:1530nm a nml:Link ; nml:name "1530nm wave between NOR and AMS" ; nmlrel:providesLink ex:link:eth:NOR-AMS-0001 . _______________________________________________ nml-wg mailing list nml-wg@ogf.org https://www.ogf.org/mailman/listinfo/nml-wg
Internet2 Spring Member Meeting April 22-25, 2012 - Arlington, Virginia http://events.internet2.edu/2012/spring-mm/