Rings are wonderfully innovative network solutions, but they do have limitations. First, in spite of all the capabilities they bring to the network, they are not particularly flexible in terms of deployment. Users of them are forced to transport their traffic along the single path that the ring provides, even if that path is a long way around from the source to the destination of the transmission. In many cases, this poses no problem, but for the many delay-sensitive applications that are emerging on the scene, such as voice over IP, interactive and distributive video, and others, the added delay can change the perceived quality of service, especially if a ring switch has occurred, that adds even more end-to-end delay. In response to this evolving perception, a new architecture has emerged on the scene. Interestingly enough, it is not a new model, but rather one that has been around for along time. Mesh architectures are suddenly enjoying great attention as the next generation of networking to inherit the crown from the pure ring. This model, shown in Figure 6-14, offers the multiple route capabilities of a dedicated network span alongside the survivable nature of a ring. The bulk of the network is clearly a collection of point-to-point facilities that provide shortest distance transport between any two end points, as illustrated by Figure 6-15. However, the collection of dotted lines clearly represents a ring, and the large number of alternate routes means that survivability is...