A Queueing Model of the Edge Node in IP over All-Optical Networks

The high demand for more bandwidth and high speed networks stimulates research in the design, optimization and performance evaluation of IP over all-optical networks. In this paper we study optical packet filling algorithm applied at ingress nodes of an all-optical network. Arriving electronic packets of variable sizes are stored at a buffer the volume of which is equal to the fixed size of optical packet. When the available space in the buffer is less than the size of an arriving packet, the stored already content of the buffer is sent inside the optical packet and the electronic packet is rescheduled for the next filling cycle. To avoid excessive delays, the optical packet is dispatched also after a specified deadline whatever is the (non-null) content of the buffer. The performance metrics we consider comprises the filling of optical packets (that means the ratio of blocks in the packet to the actual constant size of the packet) and the distribution of optical packets interdeparture times. The paper demonstrates that the variability of the size of arriving packets and the self-similarity of the input traffic have a visible impact on the both parameters.