O to manage a whole network how will the control plane protocols and the network manager interact and how will they divide the functions. As a matter of fact, several control plane functions are performed in traditional transport networks by the central network manager SO that both control plane and network manager have to be redefined in a functional sense. The ASON architecture states that the control plane is responsible for the actual resource and connection management within an automatically switched network (ASN). The con- trol plane resides in a distributed network intelligence constituted by the optical connec- tion controllers (OCCs); the OCC can run in separate workstations as the element managers but generally directly reside into the control unit of the equipments dedicated to switching at each network layer. The OCCs are interconnected via the interface called network to network interfaces (NNI) and run the control plane protocol suite having the following functions: Network topology discovery (that is, resource discovery) Address assignment to an equipment port when it is discovered and address advertisement to all the networks Signaling (connections setup, management, and tear down) Connections routing Convergent Network Management and Control Plane Connection protection/restoration Traffic engineering Resource assignment (e.g., wavelength assignment in the WDM layer, time slot assignment in the SONET layer etc.) The management plane is responsible for managing the control plane. Its responsibilities include the following: Configuration management of the control plane resources Definition of the administrative areas Control plane policies definition Few of the traditional network manager functionalities should also be maintained on the data plane entities: Fault management Performance management Accounting and security management The management plane is constituted by the central management unit, which runs the network manager, and the local management units, which run the element managers, and by 