Adaptation is between Ports, and requires the following objects:
* 2 Link instances
* 4 Port instances
* 2 Adaptation instances
* 8 relations between these instances

I propose a shortcut to define adaptation between Links, similar how 
isSerialCompoundLink also relates Link objects, bypassing the more tedious Link 
<--(isSink)-- Port --(isSource)--> Link relations.

This would only require the following objects:
* 2 Link instances
* 1 relation between these instances

This can be used in situations where a full topology description (with all ports
) is not required. Of course this is less detailed (e.g. it is not possible to 
describe the type or adaptation, or the name of the Ports)

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" /
>
    </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 .

Adaptation is between Ports, and requires the following objects:
* 2 Link instances
* 4 Port instances
* 2 Adaptation instances
* 8 relations between these instances

I propose a shortcut to define adaptation between Links, similar how 
isSerialCompoundLink also relates Link objects, bypassing the more tedious Link 
<--(isSink)-- Port --(isSource)--> Link relations.

This would only require the following objects:
* 2 Link instances
* 1 relation between these instances

This can be used in situations where a full topology description (with all ports
) is not required. Of course this is less detailed (e.g. it is not possible to 
describe the type or adaptation, or the name of the Ports)

NML:

  Link --(hasChannel)--> 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 --(hasChannel)--> l1     - True
  l0 --(hasChannel)--> l2-2   - True
  l1 --(hasChannel)--> l2-2   - True
While the following statements are all False:
  l0 --(hasChannel)--> l3     - False
  l1 --(hasChannel)--> l3     - False
  l2-2 --(hasChannel)--> 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="hasChannel">
      <nml:Port idRef="urn:ogf:network:example.net:2012:link:eth:NOR-AMS-0001" /
>
    </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:hasChannel ex:link:eth:NOR-AMS-0001 .

Need proposal

Under discussion

Define adaptation

Adaptation between links

New

Work in Progress