Impact of Traffic Delay Tolerance on Elastic Optical Networks Performance

Elastic Optical Networks (EON) are considered as a valuable solution to enhance optical networks efficiency due to their superior network spectrum use. By breaking the traditional fixed grid of WDM networks, the spectrum assigned to connection demands is adapted to their requirements. On the other hand, connection parameters such as baud-rate or modulation format are dynamically adjusted taking into account the current network conditions. Therefore, EONs fit perfectly with the heterogeneous characteristics of current and future network traffic loads. Nevertheless, when EONs are in operation, they present some weaknesses mainly derived from the spectrum fragmentation generated by the dynamic establishment and torn-down of these diverse connections. The randomness of connections generation results in the blocking of some connections even when the total load supported by the network is not so high. In this work, we analyse how traffic tolerance to delay impacts on the EON performance, and present simulation obtained results when connection demands have no strict delay constraints compared with demands which need to be real-time served.