The elastic optical networks recently come into focus in resarch as the emerging traffic calls for a more data- rate flexible, agile, reconfigurable, and resource-efficient optical network.
To meet the needs of the future Internet, the optical transmission and networking technologies are moving forward to a more efficient, flexible, and scalable direction.
Researchers investigate some promising technics (Optical-OFDM, Nyquist WDM) to make the optical spectrum gridless. In such spectrum elastic networks routing and spectrum allocation (RSA) is a more complex challenge. Spectrum elastic, gridless optical core network can cause spectrum fragmentation. We can defragment the spectrum with traffic grooming algorithms. The survivable traffic grooming is a complex problem in elastic optical networks with flexible spectrum grid.
To provide appropriate availability we use special spectrum elastic dedicated and shared path protection.
We implemented multiple RSA algorithms. We propose an RSA algorithm which simultaneously handles the routing and spectrum allocation problems. We made dynamic traffic simulations on multiple networks, and show the efficiency of the proposed SASP (Spectrum Aware Shortest Path Routing) method. We used traffic grooming to decrease spectrum fragmentation.
We implemented dedicated and shared protection and compared the efficiency, and showed the benefits of our method. If the working paths of two connections are link disjoint physically, and if their backup paths are adjacent on a fiber link, then the two backup lightpaths can share spectrum.
The method is generalizable further to anycast and multicast cases.