Quality of protection (QoP): a quantitative unifying paradigm to protection service grades

In this paper we discuss a quantitative framework for best- effort protection of the optical layer. This framework provides a way to bridge the gap between two known protection grades of fully protected connections vis-a-vis unprotected protection. The framework allows to specify the probability with which the connection will be protected, providing the customer with a full range of protection guarantees at possibly different prices. Since connections may be partially protected, the required protection bandwidth can be reduced. The amount of protection bandwidth is shown to depend on an 'equivalent survivable bandwidth.' The framework also extends to preemptable (low priority) connections and to different ring architectures.