Abstract

Multicast communication in wavelength division multiplexed (WDM) networks is traditionally supported by the assumption that the optical crossconnects are multicast capable, i.e., they are capable of switching an incoming signal to more than one output interface. A naïve method of supporting this functionality in a multicast-incapable (MI) environment is by creating a virtual topology consisting of lightpaths from the multicast source to each destination of the multicast session. For large sets of multicast requests, however, the network bandwidth consumed by such a scheme may become unacceptable due to the unicasting nature of the lightpaths. We refer to this method as achieving multicast via WDM unicast (MVWU). To support users’ multicast requests (from higher electronic layers) in MI networks, we propose two overlay solutions: drop at member node (DMN) and drop at any node (DAN). In these solutions, we achieve multicasting by creating a set of lightpath routes (possibly multiple hops) in the overlay layer from the source node of a request to each destination member. In the DMN case, we allow a lightpath route to originate/terminate only at source and destination members of a request, whereas in the DAN model we impose no such restrictions. We first consider a static traffic model, wherein the set of multicast requests is known ahead of time, and present integer linear programs (ILPs) to solve these problems (MVWU, DMN, and DAN) with the goal of minimizing the total number of wavelengths required to service the set. We also present an efficient heuristic and compare its performance to the ILP for a small network, and run simulations over real-world, large-scale networks. Moreover, we present lower bounds to calculate the minimum number of wavelengths required by the DMN and DAN models. Finally, we evaluate the performance of the heuristic (minimization of the number of wavelengths) under a dynamic traffic scenario and also evaluate the blocking performance for a fixed number of wavelengths.

© 2012 OSA

Full Article  |  PDF Article

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (16)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (8)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (21)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription