Scheduling aware dimensioning for Time-Domain Wavelength Interleaved Network

Abstract

In this paper, we present a novel approach for resource provisioning in Time-Domain Wavelength Interleaved Network (TWIN), an optical burst switching solution available for transport in regional networks, with nodes equipped with transponders composed of a fast tunable transmitter and a fixedwavelength receiver. The approach consist in allocating the number of transponders to satisfy the traffic demand, providing at the same time an optimal slot schedule for the transport of optical bursts. Apart from calculating the optimal schedule, the solution also allocates the additional slots to sources, in order to improve the level of QoS latency experienced by individual network flows during the pre-insertion queueing process. This functionality is achieved by original QoS constraints. The dimensioning method is optimal, formulated as Mixed Integer Linear Program (MILP), and it allows a trade-off between the amount of network resources allocated and the QoS performances of the optimal solution. By simulations we studied the impact of the proposed dimensioning solution on the network performances and the total network capacity achievable by TWIN. We show that our proposed latency constraint mechanism leads to insertion latency limited to few time slots only at no additional network resource cost, in a 6node mesh network. We also show that non-uniform network traffic decreases TWIN capacity efficiency (i.e., wastes resources) compared with deterministic traffic.Index Terms-Optical burst switching, network dimensioning, QoS.

A cost comparison of survivable subwavelength switching optical metro networks

“…The slot allocation repeats after these K slots, during network operation. In our previous paper [5] we proposed a dimensioning solution for TWIN which resolves the scheduling problem together with the routing and wavelength assignment problem. In the protection configuration, the slot allocation is needed simultaneously for both working and backup paths.…”

“…As in [5], we suppose that the slots that are the object of allocation are enumerated by numbers 0, 1, ..., K − 1 and that at a given moment in time, all the sources send the slots enumerated with the same number.…”

“…From the bandwidth efficiency point of view, in [5] and [6], the achievable throughputs of TWIN and POADM are studied, respectively, and it is shown that the network in both cases can achieve the capacity use efficiency of more than 90%. Both networks have a synchronous, slotted operation; the scheduling problem consists in efficiently allocating the time slots to different source-destination pairs.…”

“…In contrast to POADM, where both opportunistic and non-opportunistic slot access can be used for scheduling slots, TWIN needs to use some kind of slot reservation or grant mechanism [7]. In both cases, the slot allocation is non-separable from the network planning, and the network configuration has a strong impact on the network performances such as latency [5], [6].…”

Scalable routing, scheduling and virtualization for TWIN optical burst switching networks

“…The scheduling in TWIN has been extensively studied by different research groups, with accent on minimizing the schedule length, centralized and distributed scheduling, and different traffic dynamicity (e.g., see [3], [4], [5]). The work in [6], for the first time, simultaneously addresses the Routing and Wavelength Assignment (RWA) and scheduling problem in TWIN, and argues that these two problems shall be solved together to minimize the total network cost. The proposed dimensioning tool is an Integer Linear Program (ILP).…”