Signalling spec completed

The membership of the Optical Internetworking Forum (OIF) has approved a signalling specification for the OIF’s User Network Interface (UNI) 1.0.

The specification defines the signalling protocols implemented by client and transport network equipment from different vendors to invoke services, the mechanisms used to transport signalling messages and the auto-discovery procedures that aid signalling.

The primary service offered by the transport network over the UNI is the ability to create and delete connections on-demand. Developed by OIF’s Technical Committee, the new specification is the result of work by the Forum’s Architecture, Carrier, Operations Administration, Maintenance & Provisioning (OAM&P) and Signaling Working Groups.

‘The UNI 1.0 implementation agreement marks the beginning of a new era of interoperability in optical internetworking,’ said Steve Joiner, OIF’s Technical Committee chairman. ‘The OIF’s work towards the formalisation of a standard for UNI 1.0 marks a significant step for the industry towards the implementation of an open transport network layer. Indeed, the carriers are starting to reference the OIF UNI in their documents for network upgrades and build-outs demonstrating the growing support for this agreement.’

‘UNI 1.0 is the result of cooperation between network and equipment providers to improve the carriers’ ability to provide new services while reducing operation cost,’ said Tom Afferton, OIF board member and director of advanced transport technology and architecture for AT&T. ‘The UNI allows carriers to significantly reduce the cost of manual network operation by deploying distributed network control based on direct signaling interfaces from the users of their optical networks.’

‘The OIF’s successful interoperability demonstration of the UNI 1.0 atSupercomm 2001 signalled that the industry is ready to implement UNI 1.0,’ said Sid Chaudhuri, president of the OIF. ‘In developing UNI 1.0, the OIF has taken into consideration the work of other standards bodies and in particular has worked to develop a UNI protocol that is in alignment with the IETF’s proposed standards.’

The advent of the automatic switched transport network has necessitated thedevelopment of interoperable procedures for requesting and establishing dynamic connectivity between client layers like IP, ATM, SONET and others. The development of such procedures requires the definition of the physical interfaces between clients and the transport network, the connectivity services offered by the transport network, the signalling protocols used to invoke the services, the mechanisms used to transport signaling messages and the auto-discovery procedures that aid signalling.

As a next step to accelerate the deployment of interoperable and robust optical internetworks, the OIF is initiating efforts to develop signalling specifications for a network-to-network interface (NNI).