1. Survey on Signaling Techniques for Cognitive Networks Dzmitry KliazovichUniversity of Luxembourg, Luxembourg Fabrizio GranelliUniversity of Trento, Italy Nelson da FonsecaUniversity of Campinas, Brazil

2. Cognitive Networks From technological perspective – Evolution towards unified QoS-aware environment From business perspective – Profit on self-management and common heterogeneous platforms June 10, 20112Dzmitry Kliazovich (kliazovich@ieee.org) Cognitive networks can plan, decide, and act based on network conditions, learn to adapt future decision, all for achieving end-to-end goals

3. Cognitive Networks Cognitive networks There is a clear need for new signaling techniques and design approaches. June 10, 20113Dzmitry Kliazovich (kliazovich@ieee.org) Modular design Physical Datalink Network Transport Application

4. Signaling Techniques Node-level signaling – Information sharing between different layers of the protocol stack to achieve node-centric goals Network-level signaling – Information sharing between network nodes to achieve end-to-end goals June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)4

5. Signaling Techniques: Intra-Node Interlayer signaling pipe Direction: Layer-to-layer along the packet flow Association: Signaling is associated with packets Carriers: Packet headers or kernel packet structures June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)5 Q. Wang and M. A. Abu-Rgheff, “Cross-layer signaling for nextgeneration wireless systems,” IEEE Wireless Communications and Networking (WCNC), pp. 1084 – 1089, 2003.

6. Signaling Techniques: Intra-Node Direct interlayer communication Direction: Bidirectional between any layers Association: signaling is not associated with data flow Carriers: ICMP packets or kernel call-back functions June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)6 Q. Wang and M. A. Abu-Rgheff, “Cross-layer signaling for nextgeneration wireless systems,” IEEE Wireless Communications and Networking (WCNC), pp. 1084 – 1089, 2003.

7. Signaling Techniques: Intra-Node Central cognitive plane Direction: Any-to-any Association: maintained only if explicitly mentioned Carriers: kernel functions June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)7 V. T. Raisinghani and S. Iyer, “Cross Layer Feedback Architecture for Mobile Device Protocol Stacks,” IEEE Communications Magazine, vol. 44, no. 1, pp. 85 – 92, 2006 Physical Datalink Network Transport Application Signaling plane

8. Signaling Techniques: Network Level Packet headers Direction: Along with a packet flow Association: signaling information is associated with data Carriers: packet headers June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)8 V. T. Raisinghani and S. Iyer, “Cross Layer Feedback Architecture for Mobile Device Protocol Stacks,” IEEE Communications Magazine, vol. 44, no. 1, pp. 85 – 92, 2006

9. Signaling Techniques: Network Level ICMP messages Direction: Anywhere in the network Association: not maintained Carriers: ICMP packets June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)9

10. Signaling Techniques: Network Level Explicit notification schemes – Congestion (ECN), loss (ELN), bad state (EBSN) Direction: Signaling loop through the receiver Association: signaling information associated with data flow Carriers: packet headers or ICMP messages June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)10

11. Signaling Techniques: Network Level Wireless channel information Direction: Base station broadcasts to entire cell Association: Not maintained Carriers: B roadcast out-of-band channel June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)11 B.-J. Kim, “A network service providing wireless channel information for adaptive mobile applications: I: Proposal,” IEEE International Conference on Communications (ICC), pp. 1345 – 1351, 2001.

12. Common Cognitive Node Architecture June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)12

13. Signaling Techniques: Comparison Metrics Signaling method Scope Type of signaling Signaling latency Communication overhead In-band/Out-of-band Direction of signaling Packet association June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)13

14. Signaling Techniques: Comparison June 10, 2011Dzmitry Kliazovich (kliazovich@ieee.org)14

15. Conclusions Signaling is a key enabler for cognitive network implementations using existing protocol stacks Proper signaling architectures are yet to be designed Upcoming solutions are envisioned to adapt a combination of intra-node and network-level signaling June 10, 201115Dzmitry Kliazovich (kliazovich@ieee.org)

16. Thank you! Contact information of the authors: Dzmitry Kliazovich University of Luxembourg kliazovich@ieee.org Fabrizio Granelli University of Trento, Italy granelli@disi.unitn.it Nelson L. S. da Fonseca State University of Campinas, Brazil nfonseca@ic.unicamp.br