MULTIOPTI Research Program

Multicasting and groupcasting with physical layer constraints in metropolitan optical networks with mesh topologies

Technical Objectives

The proposed project covers two important areas, optical multicasting and optical groupcasting, and looks at finding a comprehensive solution for the provisioning problem in metropolitan area transparent optical networks. The specific scientific and technological objectives of the proposed project are as follows:

(1) We will develop algorithms for routing full wavelength and sub-rate (grooming) multicast connections for metropolitan area transparent optical networks, while taking into account the physical impairments that the signals encounter along the path. The number of connections that can be established (compared to the connection requests) will be our performance metric in this case.

(2) We will extend the provisioning of multicast connections to include the provisioning of protected multicast trees, utilizing dedicated as well as shared protection techniques. Redundant capacity requirements and recovery times will be analyzed and evaluated.

(3) We will develop algorithms to route (and groom) groupcast connections in optical networks, again taking into account the physical layer constraints. Static and dynamic groupcast will be implemented.

(4) We will design algorithms to provision protected groupcast services in transparent optical networks.

(5) We will develop a software simulation tool that can provision all types of connections (unicast, multicast, or groupcast), having full-wavelength or lower-rate traffic demands and protected or unprotected characteristics, while taking into consideration the physical layer effects. Test case networks will be used to evaluate the validity of the simulation tool.

We anticipate that the project will lead to the following major innovations:

(1) Development and evaluation of novel algorithms for the provisioning of dynamic multicast connections in transparent optical networks. These connections will be set-up either as full wavelengths, or they will be lower-rate connections that will be routed through existing wavelengths that have enough available capacity to accommodate them (traffic grooming). Homogeneous and heterogeneous traffic provisioning techniques will be also accommodated for these algorithms. Modeling techniques and methodologies (via the Q-budgeting approach) will be developed to account for the physical layer impairments, and these models will be used while provisioning the new connections. The novel algorithms developed will be able to calculate the quality of the optical signal for the incoming connection, as well as the quality of the optical signals for the connections already on the network assuming the new connection will be admitted. This way the software will be able to make an informed decision whether to accept the new multicast connection into the network.

(2) Development of novel protection mechanisms for the multicast connections that use the models developed for the physical layer impairments to provision the new protected multicast connections. Dedicated and shared protection techniques will be implemented and evaluated.

(3) Development and evaluation of novel algorithms for the provisioning of static and dynamic groupcast connections in transparent optical networks. Traffic grooming and homogeneous as well as heterogeneous traffic provisioning techniques will be implemented. Information on the physical layer impairments once again be utilized to decide whether a groupcast connection can be admitted into the network.

(4) Development of novel protection mechanisms for the groupcast connections that use the models developed for the physical layer impairments.

(5) Development of an integrated software simulation tool that can provision all types of traffic demands (multicast/groupcast,� full-wavelength/low-rate, protected/unprotected) while at the same time taking into account physical layer effects.