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Connection-oriented network technologies such as Asynchronous Transfer Mode are capable, in principle, of supporting many different services. Control and management of these networks, however, are often rooted in the monolithic and inflexible design of a traditional telephone network. This is unfortunate, as the speed at which new services can be introduced depends on the flexibility of the control and management system. Recent attempts at opening up network control and management have achieved promising results. Using non-proprietary interfaces and strict partitioning of network resources, multiple control systems are allowed to be active simultaneously in the same physical network. Each control system controls a virtual network, i.e. a subset of the network resources. Success of this approach has been limited, however, due to the inflexibility of its software components. The way in which resources are partitioned, or virtual networks are built, is determined once and for all at implementation time. Similarly, the control systems themselves are rigid. Building and running a specialised control system in a separate virtual network for each application area, although possible in principle, is too heavy-weight for many applications. This dissertation presents a solution for these problems, the implementation of which is called the Haboob. It represents the next step in opening up the network, by permitting customisation of all aspects of network control, including the software components. For this purpose, an agent environment, called the Sandbox, was developed, which is both language and implementation independent, and general enough to be used for purposes other than network control as well. It includes a simple uniform way for agents on different nodes to interact. Various mechanisms enforce protection and access control. Sandboxes have been successfully introduced to all components that make up the network control and management system. Code running in Sandboxes is able to extend or modify the functionality of the components. This is called elastic behaviour. The customisability of all aspects of network control and management eases the development of new services. |
