Cognitive Networks: Towards Self-Aware Networks

2.4. The FOCALE Architecture

FOCALE was built to apply autonomic principles to network management. As such, it is different than common autonomic architectures ^[], which are applied to non-networking components of IT systems.

FOCALE stands for Foundation – Observation – Comparison – Action – Learn – rEason. It was named because these six elements describe the six key principles required to support autonomic networking.

The idea behind FOCALE is simple enough, and is summarized as follows. As discussed in Sections 2.2 and 2.3, autonomic principles manage complexity while enabling the system to adjust to the changing demands of its users and environmental conditions. In order for the network to dynamically adjust the services and resources that it provides, its components must first be appropriately configured and reconfigured. Assume that behavior can be defined using a set of finite state machines, and that the configuration of each device is determined from this information. FOCALE is a closed loop system, in which the current state of the managed element is calculated, compared to the desired state (defined in the finite state machines), and then action taken if the two states aren't equal. This can be expanded as follows: define a closed control loop, in which the autonomic system senses changes in itself and its environment; those changes are then analyzed to ensure that business goals and objectives are still being met. If they are, keep monitoring; if they aren't, then plan ...