12.1. Introduction

As carriers build global and national networks, it becomes necessary to systematically partition these networks into control domains, that is, subnetworks in which a particular control paradigm or protocol is employed. Control domains are often referred to simply as domains (see Chapter 5).

From a network control perspective, the motivations for dividing a network into domains are:

  • To define administrative boundaries

  • To allow for scalability of routing and signaling

  • To isolate portions of the network for security or reliability, and

  • To accommodate technology differences between systems, for example, by partitioning a single carrier's network into separate single vendor subnetworks

Figure 12-1 illustrates the partitioning of a ...

Get Optical Network Control: Architecture, Protocols, and Standards now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.