UC 1h: Unconstrained asymmetric DSR Service Provisioning, UNI DSR E-NNI OTUk grey interface needs some clarifications.
- Which layer protocol qualifier on CSEPs?
- How to represent Top Connections which are not terminated in the managed domain?
- Consider that UC 1h shall be supported by TAPI 2.1.3 version.
Nigel Davis edited the above picture to show the possible "symmetric transit scenario with client monitoring":
Confirmed agreements on the following rules in case of access and transit scenarios:
- Access scenario, the "semi-terminated" Top Connection lists the CEP where the Connection is terminated (UNI side) and the available server layer CEP at ENNI side ("end point projection") where the connection is delivered within a server container.
- Doing so the Top Connection provides the best topological information. The ENNI CEP is intended as the point in the topology where the Connection is delivered to the external domain.
- In other words, the ENNI CEP, e.g. the ODU4 CEP, is the one which supports the Connection bandwidth (ODU2 time slot).
- Transit scenario, the Connectivity Service (and its CSEPs) could be specified at any layer protocol name/qualifier, as this is the intent specification.
- In other words, the CS represents the intent for a connection between SIPs, the CSEPs the intent for the amount and type of bandwidth on these SIPs.
- The only relationship between actual-local SIP/NEP capabilities and CS/CSEPs layer protocol name/qualifier is the known rule of technology stack (e.g. a 10G DSR can be potentially supported by an ODU4 container, the reverse case not). The server controller will allocate the appropriate resources at same and/or server layers.
- In other words, considering the 3rd picture above, the DSR CS can be provisioned even if the result does NOT include any DSR CEP/Connection, e.g. because transparently delivered by an ODU2 container.
- Transit scenario, the "unterminated" Top Connection shall be represented if there is at least one monitoring point in the transit managed domain (see 2nd and 3rd pictures above).
- E.g. in case the 10G DSR is transparently delivered by an ODU2 container, then the DSR (Top) Connection will not be represented, but only the ODU2 (Top) Connection (3rd picture above).
- The ENNI CSEP could indicate the DSR layer qualifier, because CSEP is just providing intent information regarding the portion of (DSR) bandwidth that the ENNI SIP/NEP shall support.
- The server controller will provide the supporting Connections at the layer protocol which is actually managed in the domain.
- ODU related information (e.g. preferred time slot) can be provisioned as server layer constraint.
- The CSEP to CEP reference can be deprecated as could be difficult to be represented / maintaned in complex scenarios. The CSEP indicates the intent for a bandwidth portion of a SIP.
- The service-to-connection relationship is modeled by the CEPs of the Connections which support the ConnectivityService.