Cognitive network

In communication networks, cognitive network (CN) is a new type of data network that makes use of cutting edge technology from several research areas (i.e. machine learning, knowledge representation, computer network, network management) to solve some problems current networks are faced with. Cognitive network is different from cognitive radio as it covers all the layers of the OSI model (not only layers 1 and 2 as with cognitive radio).

History

One of the attempts to define the concept of cognitive network was made in 2005 by Thomas, DaSilva and MacKenzie^[1] and is based on an older idea of the Knowledge Plane described by Clark, Partridge, Ramming and Wroclawski^[2]. Since then, several research activities in the area have emerged. A survey^[3] and an edited book^[4] reveal some of these efforts.

The Knowledge Plane is "a pervasive system within the network that builds and maintains high level models of what the network is supposed to do, in order to provide services and advice to other elements of the network" ^[2].

Definition

In ^[1], the authors define the CN as a network with a cognitive process that can perceive current network conditions, plan, decide, act on those conditions, learn from the consequences of its actions, all while following end-to-end goals. This loop, the cognition loop, senses the environment, plans actions according to input from sensors and network policies, decides which scenario fits best its end-to-end purpose using a reasoning engine, and finally acts on the chosen scenario as discussed in the previous section. The system learns from the past (situations, plans, decisions, actions) and uses this knowledge to improve the decisions in the future.

This definition of CN does not explicitly mention the knowledge of the network; it only describes the cognitive loop and adds end-to-end goals that would distinguish it from CR or so called cognitive layers. This definition of CN seems to be incomplete since it lacks knowledge which is an important component of a cognitive system as discussed in ^[2], ^[4], ^[5] and ^[6].

In particular, Balamuralidhar and Prasad ^[6] gives an interesting view of the role of ontological knowledge representation: “The persistent nature of this ontology enables proactiveness and robustness to ‘ignorable events’ while the unitary nature enables end-to-end adaptations.” We consider this statement essential for CNs.

In ^[3], CN is seen as a communication network augmented by a knowledge plane that can span vertically over layers (making use of cross-layer design) and/or horizontally across technologies and nodes (covering a heterogeneous environment). The knowledge plane needs at least two elements:

• A representation of relevant knowledge about the scope (device, homogeneous network, heterogeneous network, etc.).
• A cognition loop which uses Artificial Intelligence techniques inside its states (learning techniques, decision making techniques, etc.).

See also

• Cognitive radio
• Cross-layer optimization
• Artificial intelligence
• Machine learning
• Knowledge representation
• Computer network
• End-to-end principle
• Cognitive Plane

References

1. ^ ^{a b} R.W. Thomas, L.A. DaSilva, A.B. MacKenzie, "Cognitive networks", in: Proceedings of the First IEEE International Symposium on New Frontiers in Dynamic Spectrum Access Networks, Baltimore, MD, USA, November 8–11, 2005.
2. ^ ^{a b c} D.D. Clark, C. Partrige, J.C. Ramming, J.T. Wroclawski, "A knowledge plane for the internet", in: Proceedings of the SIGCOMM 2003, Karlsruhe, Germany, August 25–29, 2003.
3. ^ ^{a b} C. Fortuna, M. Mohorcic, "Trends in the development of communication networks: Cognitive networks", Computer Networks, 2009.
4. ^ ^{a b} Q. Mahmoud, "Cognitive Networks: Towards Self-Aware Networks", John Wiley and Sons, 2007, ISBN 9780470061961.
5. ^ J. Mitola, "Cognitive Radio – An Integrated Agent Architecture for Software Defined Radio", Ph.D. Dissertation, Royal Institute of Technology, Kista, Sweden, May 8, 2000
6. ^ ^{a b} P. Balamuralidhar and R. Prasad, "A context driven architecture for cognitive nodes", Wireless Personal Communications 45 (2008), pp. 423–434.

External links

• "IEEE Technical Committee on Cognitive Networks"
• "Alcatel-Lucent Chair in Flexible Radio - Theoretical Foundations of Flexible Radios"