Establishing Lightpaths of an Optical Ring for Distributed Computing Environment

We study optical lightpath networking for distributed computing environment. Lightpath networks are suitable to network-wide distributed computing because the bandwidth is assured once a lightpath is established. In this paper, we dynamically configure a unidirectional optical ring that is used for multipoint-to-multipoint communications among hosts in a group. The ring consists of multiple unidirectional lightpaths. Each host in the group is an endpoint of the lightpath. The routing of the network is usually specific to point-to-point communications. We propose a ring composition algorithm that finds the least-cost set of lightpaths of the optical ring under this routing. In this algorithm, a parent host finds a destination host of which route from the host is the least-cost route among routes to hosts in the group. We also propose backward signaling methods that are specific to the establishment of the lightpaths for the ring composition. Since the signaling for lightpath establishment is well adjusted to RSVP-TE for GMPLS, an implementation of the ring composition can be accelerated. Through simulation experiments, we find the proposed ring composition method generates lightpaths for the optical ring with less wavelength resources. The smart signaling accelerates the efficiency of network resources. The clear reduction of blocking probability of establishing a ring for a group is found from the simulation result.