Comparison of Schemes for Provision of Differentiated Availability-Guaranteed Services Using Dedicated Protection

In the coming next generation network, the introduction of new services with different quality of service (QoS) requirements combined with cost conscious customers who make cost/utility trade-offs, yields a need for the network operators to be able to offer different levels of guaranteed availability. Protection techniques are used to provide alternative paths to a connection in case of failure of the working path. This paper considers dedicated protection, where the bandwidth of the protection paths is reserved exclusively. The challenge is to find schemes that can provide the guaranteed availability level requested by each connection while at the same time use bandwidth efficiently. This may be achieved by applying availability-aware protection schemes that allocate only the minimum amount of backup resources needed to meet the availability requirement of each connection. In the literature, some schemes for providing differentiated availability-guaranteed services have been proposed. There has, however, been no studies that quantitatively compare different schemes. The main contribution of this paper is to provide the first comparison of schemes for differentiated availability-guaranteed services. In this paper, three schemes which vary in complexity, flexibility and bandwidth-efficiency are compared. The schemes are compared by simulation through case studies, where the common path protection scheme serves as a reference.