scope:

This Recommendation covers the areas associated with the signalling aspects of the automatically switched optical network (ASON). Specifically, it provides the signalling requirements for the communications of call controller, connection controller and link resource manager. This Recommendation currently specifies support for multiple connections per call, call modification and calls across multiple layers. Areas covered include:

- attribute specifications;

- message specifications;

- signal flows;

- management of DCM.

Other areas of ASON such as routing mechanisms, parameters associated with routing mechanisms, discovery, and naming and addressing are outside the scope of this Recommendation. This Recommendation provides the attribute and message specification, and signalling exchange that allows support for hierarchical, source and step-by-step routing.

This Recommendation uses the architecture and functional requirements as outlined in [ITU-T G.8080] as the basis for the specification. This Recommendation aims to provide a protocol-neutral approach to describe the capability sets of the DCM. Capabilities specified in this Recommendation include support for soft permanent connections and switched connections.

In order to allow for interworking between multiple specific protocol implementations, an interworking function may need to be specified. This is currently for further study.

Transport of the DCM message sets is via a data communication network (DCN). One possible option for a DCN is described in [ITU-T G.7712].

In order to provide an automated DCM mechanism, a priori knowledge of the network resources is needed. These resources may be manually provisioned or automatically discovered. Automatic discovery of the topology and the resources may be performed as per [ITU-T G.7714].