Reliability evaluation of SBC\´s "fiber to the node" network

The FTTN/FTTP strategy delivers an optimal balance of network capability, cost, speed of deployment, reliability and convenience for customers. Reliability is one of the key aspects of this new architecture, especially since it delivers delay-sensitive voice and video services in addition to data services. This paper provides the results of the most recent FTTN network reliability studies conducted by SBC. These studies include availability/downtime analysis of various segments of the network, from the residential gateway to the fiber nodes in the neighborhood as well as the network equipment in the central offices and video hub offices. The paper also addresses layer 1 and layer 2/3 restoration and protection mechanisms as they apply to the FTTN network, and it compares applicable protocols (1+1 & M:N redundancies, MPLS, VRRP, etc.) in light of the services they are protecting and the customer impact they have. The paper presents the diversity and availability options for various segments relative to each other, showing how the access network has a major impact on the reliability, while illustrating the stringent requirement for the backbone video network