scope:

This Recommendation defines the architecture requirements for a data communication network (DCN) which may support distributed management communications related to the telecommunication management network (TMN), distributed control plane communications (e.g., signalling and routing) related to the automatically switched optical network (ASON), and other distributed communications (e.g., orderwire or voice communications, software download). The DCN architecture considers networks that are IP-only, OSI-only, and mixed (i.e., support both IP and OSI). The interworking between parts of the DCN supporting IP-only, parts supporting OSIonly, and parts supporting both IP and OSI are also specified.

The DCN provides Layer 1 (physical), Layer 2 (data-link) and Layer 3 (network) functionality and consists of routing/switching functionality interconnected via links. These links can be implemented over various interfaces, including wide area network (WAN) interfaces, local area network (LAN) interfaces, and embedded communication channels (ECCs).

Various applications (e.g., TMN, ASON, etc.) require a packet-based communication network to transport information between various components. For example, the TMN requires a communication network, which is referred to as the management communication network (MCN) to transport management messages between TMN components (e.g., NEF component and OSF component). ASON requires a communication network, which is referred to as the signalling communication network (SCN) to transport signalling and routing messages between ASON components (e.g., CC components and RC components). This Recommendation specifies data communication functions that can be used to support one or more application's communication network.

The data communication functions provided in this Recommendation support connection-less network services. Additional functions may be added in future versions of this Recommendation to support connection-oriented network services.

This 2008 revision of the Recommendation adds the definition of the OTN ECC data-link layer termination function and the transport MPLS (T-MPLS) SCC data link layer termination function.