Data communication networks in ASON: lessons learned

Experience is the name everyone gives to their mistakes. Automatically Switched Optical Networks (ASON) get a lot of tradion in the market place. ASON is an lTU-T standard, describing the network architecture with the idea to exploit the Data Communication Network (DCN) for communication purposes. However deployed DCN networks were designed for management purposes, now the requirements for availability in ASON environments are much higher. Control planes which are used in ASON are directly linked with service availability and the quality of the DCN which is carrying the control plane messages. Design and resilience choices of the DCN need to be adapted to the control plane implementation and vice versa, control plane implementations have to take into account the DCN limitations. This inter-dependency has often been forgotten in the past but experience shows that such issues can become service affecting.