Hop constraint-based capacity fairness control in IP-over-WDM networks

In this article, we consider the capacity fairness problem in IP-over-WDM networks. Since connections with different bandwidth granularities may be established over a shared lightpath, fairness in bandwidth allocation among different users becomes a crucial problem. A simple, yet efficient hop constraint-based admission control scheme is proposed to accommodate more high-bandwidth requests. Through rejecting some of the low-capacity requests that would go through alternative paths with more hops and thus would consume a larger amount of bandwidth, the blocking probability of high-capacity requests reduces notably. Numerical results show that this proposal achieves significant improvement in capacity fairness without raising the overall blocking probability. In addition, it achieves excellent fairness performance at both light and heavy loads by selecting the rejection probability dynamically.