On service provisioning using light-trails in WDM optical networks with waveband switching

Abstract

As the number of wavelengths in a single optical fiber increases, so does the number of ports needed for wavelength switching in optical cross-connects (OXCs), which may significantly increase the cost and difficulty associated with controlling large OXCs. Waveband switching (WBS) treats several wavelengths as a bundle that is switched through a single port if they share the same switch route, so that the number of ports needed can be reduced. On the other hand, light-trails in wavelength division multiplexing (WDM) optical networks allow intermediate nodes on established optical paths to access the data paths whereas lightpaths only allow two end nodes to access the data paths. Therefore, light-trails offer significantly better flexibility for service provisioning and traffic grooming. In this article, we study service provisioning using light-trails in WDM optical networks with the WBS capability under a static traffic model. For comparison, integer linear programs are formulated for establishing light-trails with and without WBS. Numerical studies show that in certain cases, service provisioning with WBS in light-trail networks can reduce the number of ports needed while providing a more flexible subwavelength service provisioning capability. However, contrary to intuition, in most cases applying the WBS technique requires more ports in OXCs in light-trail networks. This study provides insights into the network design problem that applies the WBS technology to light-trail based optical networks.

On Dynamic Multicast Traffic Provisioning with Grooming Capabilities Support in Light-Trail Networks

“…In a light-trail, the first node is called the convener node and the last node is called the end node. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] If a light-trail is composed of n nodes, it can support at most 2…”

“…For better bandwidth utilization, light-trails have been proposed as a promising solution. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Moreover, it is seldom that a traffic flow in IP-centric networks requires bandwidth around the entire per wavelength capacity. Based on this rationale, it is evident that lightpath is not flexible enough and would cause vital bandwidth wastage under such a dynamic regime.…”

MAC protocol with delay-aware adaptive round time for split light-trail

“…LT has been considered as an attractive solution for optical networks to support emerging services such as videoon-demand, pseudo-wires, data-centers, etc. Extensive researches have been devoted to addressing the problems in LT networks, such as traffic grooming [2][3][4], node architecture [5,6] and media access control (MAC) protocol [7][8][9][10][11][12][13].…”

DAART: Delay-aware Adaptive Round Time MAC Protocol to Improve Throughput in Light-trail Networks

“…As a result, LT has been considered as an attractive solution for optical networks to support emerging services such as video-on-demand, pseudo-wires, data-centers, etc. Extensive researches have been devoted to addressing the problems in LT networks, such as traffic grooming [2][3][4], node architecture [5][6] and media access control (MAC) protocol [1,[7][8][9][10][11][12].…”