Pablo Vidales (alumni)
User ID:pav25
Position:PhD Approved
Homepage: /Research /DTG /~pav25 /index.htm
Overview and Interests
I did my PhD on mobile networking. In my dissertation, I studied Mobile IP in heterogeneous environments. I overcome some weaknesses of the protocol by introducing and evaluating practical methods and solutions that minimise connection disruptions and support transparent mobility in future communication systems. Firstly, I show that repercussions on the link can be minimised by using the appropriate architecture. Recently, it has been considered necessary to integrate commercially-available wireless networks into a universal access platform, also known as the fourth generation (4G) communication system. I present the design and deployment of an experimental testbed that implements this 4G model, enabling roaming between the most popular wireless and wired technologies. In addition, the testbed is used to evaluate Mobile IPv6 performance in heterogeneous environments, and identify the weaknesses of this protocol to manage seamless roaming between different technologies. Secondly, I demonstrate that Mobile IPv6 can be optimised by modifying its current specification without altering the core functionality or adding significant overhead. My experimental results show the improvements in vertical handover latency, which varied between small time reductions and ``zero'' latency, for the case of soft handovers. Finally, I claim that minimising the latency is not enough to enable seamless roaming in highly-integrated and diverse networks. Therefore, I show the design and implementation of PROTON, a policy-based solution to assist nomadic users. To validate the strength of my proposal, I evaluate PROTON using the testbed, and demonstrate that it is possible to offer suitable mobility support in next generation systems, whilst handling the complexities and dynamic behaviour posed by the environment.

1. Pablo Vidales, Carlos J. Bernardos, Ignacio Soto, David Cottingham, Javier Baliosian, Jon Crowcroft, "MIPv6 Experimental Evaluation using Overlay Networks," Computer Networks, vol. 51, no. 10, pp. 2892-2915, Elsevier, Jul 2007

2. Glenford Mapp, David N. Cottingham, Fatema Shaikh, Pablo Vidales, Leo Patanapongpibul, Javier Balioisian, Jon Crowcroft, "An Architectural Framework for Heterogeneous Networking," International Conference on Wireless Information Networks and Systems (WINSYS), Aug 2006

3. P. Vidales, J. Baliosian, J. Serrat, G. Mapp, F. Stajano, A. Hopper, "Autonomic Systems for Mobility Support in 4G Networks," IEEE Journal on Selected Areas in Communications, vol. 23, no. 12, IEEE, Dec 2005

4. Pablo Vidales, "Seamless Mobility in 4G Systems," Technical Report, UCAM-CL-TR-656, University of Cambridge, Nov 2005

5. Pablo Vidales, "Seamless mobility in 4G systems," PhD thesis, University of Cambridge, Computer Laboratory, Nov 2005

6. David N. Cottingham, Pablo A. Vidales, "Is Latency the Real Enemy in Next Generation Networks?," First International Workshop on Convergence of Heterogeneous Wireless Networks, Jul 2005

7. P. Vidales, C.J. Bernardos, G. Mapp, F. Stajano, J. Crowcroft, "A Practical Approach for 4G Systems: Deployment of Overlay Networks," First International Conference on Testbeds and Research Infrastructures for the DEvelopment of NeTworks and COMmunities (Tridentcom 2005 Best Paper Award), IEEE Computer Society Press, Feb 2005

8. Pablo Vidales, Leo Patanapongpibul, Glenford Mapp, Andy Hopper, "Experiences with Heterogeneous Wireless Networks - Unveiling the Challenges," Second International Working Conference on Performance Modeling and Evaluation of Heterogeneous Networks (HET-NETs), Jul 2004

9. P. Vidales, R. Chakravorty, C. Policroniades, "PROTON: A Policy-based Solution for Future 4G devices," 5th. IEEE International Workshop on Policies for Distributed Systems and Networks (IEEE POLICY 2004), Jun 2004

10. R. Chakravorty, P. Vidales, K. Subramanian, I. Pratt, J. Crowcroft, "Performance Issues with Vertical Handovers - Experiences from GPRS Cellular and WLAN hot-spots Integration," Second IEEE International Conference on Pervasive Computing and Communications, Mar 2004

11. Pablo Vidales, Leo B Patanapongpibul, Rajiv Chakravorty, "Ubiquitous Networking in Heterogeneous Environments," 8th International Workshop on Mobile Multimedia Communications (MoMuC), Munich, Germany, Oct 2003

12. Rajiv Chakravorty, Pablo Vidales, Kavitha Subramanian, Ian Pratt, Jon Crowcroft, "Practical Experiences with Wired-Wireless and Wireless Networks Integration using Mobile IPv6," ACM Mobile Computing and Communications Review, vol. 7, no. 4, pp. 47-49, ACM Press, Oct 2003

13. Calicrates Policroniades, Rajiv Chakravorty, Pablo Vidales, "A Data Repository for Fine-Grained Adaptation in Heterogeneous Environments," 3rd ACM Workshop on Data Engineering for Wireless and Mobile Access (in conjuction with ACM MobiCom 2003), Sep 2003

14. P. Vidales, F. Stajano, "The Sentient Car: Context-Aware Automotive Telematics," IEE Workshop on Location Based Services (a condensed version appears as a poster in Ubicomp 2002), IEE press, Sep 2002