Better bounds for minimizing SONET ADMs

Better Bounds for Minimizing SONET ADMs

SONET add-drop multiplexers (ADMs) are the dominant cost factor in SONET /WDM rings. The number of SONET ADMs required by a set of traffic streams is determined by the routing and wavelength assignment of the traffic streams. Following previous work, we consider the problem where the route of each traffic stream is given as input, and we need to assign wavelengths so as to minimize the total nu...

On Minimizing the Numbers of ADMs– Better Bounds for an Algorithm with Preprocessing∗

Minimizing the number of electronic switches in optical networks is a main research topic in recent studies. In such networks we assign colors to a given set of lightpaths. Thus the lightpaths are partitioned into cycles and paths, and the switching cost is minimized when the number of paths is minimized. The problem of minimizing the switching cost is NP-hard. A basic approximation algorithm f...

The chord version for SONET ADMs minimization

We consider a problem which arises in optical routing. WDM/SONET rings are a network architecture used by telecommunications carriers for traffic streams. The dominant cost factor in such networks is the total number of add-drop multiplexers (ADMs) used. A list of traffic streams to be routed between pairs of nodes is given. In this paper we consider the problem where we need to assign a route ...

A 7/5 + ǫ Approximation Scheme for Minimizing the Number of ADMs in SONET Rings

SONET ADMs are dominant cost factors in WDM/SONET rings. Whereas most previous papers on the topic concentrated on the number of wavelengths assigned to a given set of lightpaths, more recent papers argue that the number of ADMs is a more realistic cost measure. Some of these works discuss various heuristic algorithms for this problem, and the best known result is a 3/2 approximation scheme in ...

Minimizing SONET ADMs in unidirectional WDM rings with grooming ratio 3