A connectivity management system for vehicular telemedicine applications in heterogeneous networks

ABSTRACT

Wireless access technologies such as UMTS with HSPA extensions, WiMAX, and Flash-OFDM and the convergence towards next generation heterogeneous networks enable the realization of always best connected scenarios. As the resulting heterogeneous networks become easier to access and more reliable to depend on, novel telemedicine services such as vehicular emergency applications emerge. Due to their life-critical characteristics, these applications require connectivity throughout the heterogeneous network. In this study, we propose MIPGATE, our mobile connectivity gateway for vehicular applications in next generation heterogeneous networks. MIPGATE contains modules for the access technologies currently available and a decision mechanism to switch intelligently to the connection offering the most suitable conditions. Link layer triggers and additional context information are used to optimize the handover decision process. MIPGATE is deployed within StrokeNet, a mobile telemedicine project for the remote diagnosis of stroke patients using real-time audio and videoconferencing. The MIPGATE system is validated through measurements on throughput, delay, packet loss, and handover latencies using public wireless network infrastructures with the UMTS technology and a Beyond-3G testbed featuring a Flash-OFDM test network. For the payload packets, mean handover times of 118 ms in case of handovers to UMTS/HSDPA and 23 ms in case of handovers to Flash-OFDM have been achieved in a real-world network setup. The overall packet loss rate is 0.21% and equally distributed over the duration of the measurements. The results show that MIPGATE supports network connectivity under mobility as required by novel vehicular telemedicine applications and demanding real-time services.

REFERENCES

• 1: 3rd Generation Partnership Project, Technical Specification Group Services and System Aspects. 3GPP system to Wireless Local Area Network (WLAN) Interworking, System description (Release 7), 3GPP TS 23.234 V7.6.0 edition, December 2007.
• 2: 3rd Generation Partnership Project 2. 3GPP2 - WLAN Interworking - Stage 1 Requirements, 3GPP2 TSG-S.R0087-0 V1.0 edition, August 2004.
• 3: E. Gustafsson and A. Jonsson. Always best connected. Wireless Communications, IEEE {see also IEEE Personal Communications}, 10(1):49--55, Feb. 2003.
• 4: K. Shimizu. Telemedicine by mobile communication. Engineering in Medicine and Biology Magazine, IEEE, 18(4):32--44, Jul/Aug 1999.
• 5: StrokeNet Project - Networked Intelligence for Holistic Stroke Treatment. http://www.strokenet.de. {Online; accessed November 2007}.
• 6: S. Pavlopoulos, E. Kyriacou, A. Berler, S. Dembeyiotis, and D. Koutsouris. A novel emergency telemedicine system based on wireless communication technology-ambulance. Information Technology in Biomedicine, IEEE Transactions on, 2(4):261--267, Dec 1998.
• 7: D. Konstantas, V. Jones, and R. Herzog. Mobihealth - innovative 2.5 / 3g mobile services and applications for healthcare. In Proceedings of the 11th IST Mobile and Wireless Communications Summit, Thessaloniki, Greece, June 2002.
• 8: Y. Chu and A. Ganz. A mobile teletrauma system using 3g networks. Information Technology in Biomedicine, IEEE Transactions on, 8(4):456--462, Dec. 2004.
• 9: J. R. Gallego, A. Hernandez-Solana, M. Canales, J. Lafuente, A. Valdovinos, and J. Fernandez-Navajas. Performance analysis of multiplexed medical data transmission for mobile emergency care over the umts channel. Information Technology in Biomedicine, IEEE Transactions on, 9(1):13--22, March 2005.
• 10: S. Garawi, R. S. H. Istepanian, and M. A. Abu-Rgheff. 3g wireless communications for mobile robotic tele-ultrasonography systems. Communications Magazine, IEEE, 44(4):91--96, April 2006.
• 11: ITU-T recommendation G.114. Technical report, International Telecommunication Union, 1993.
• 12: C. Perkins, IP Mobility Support for IPv4, RFC Editor, 2002
• 13: D. Johnson, C. Perkins, and J. Arkko. Mobility Support in IPv6. RFC 3775 (Proposed Standard), June 2004.
• 14: J. Rosenberg , H. Schulzrinne , G. Camarillo , A. Johnston , J. Peterson , R. Sparks , M. Handley , E. Schooler, SIP: Session Initiation Protocol, RFC Editor, 2002
• 15: T. Henderson. End-Host Mobility and Multihoming with the Host Identity Protocol. Internet draft, March 2007.
• 16: V. Devarapalli, R. Wakikawa, A. Petrescu, and P. Thubert. Network Mobility (NEMO) Basic Support Protocol. RFC 3963 (Proposed Standard), January 2005.
• 17: IEEE Std P802.21/D05.00, IEEE Standard for Local and Metropolitan Area Networks: Media Independent Handoff Services. Technical report, April 2007.
• 18: F. Teraoka, K. Gogo, K. Mitsuya, R. Shibui, and K. Mitani. Unified l2 abstractions for l3-driven fast handover. Internet draft, February 2007.
• 19: A gps service daemon, 2007. {Online; accessed November 2007}.
• 20: F. Steuer, M. Elkotob, S. Albayrak, and A. Steinbach. Testbed for mobile network operator scenarios. Testbeds and Research Infrastructures for the Development of Networks and Communities, 2006. TRIDENTCOM 2006. 2nd International Conference on, pages 10 pp.-, 1--3 March 2006.
• 21: JTG Traffic Generator, 2007. {Online; accessed July 2007}.
• 22: tcpdump/libpcap public repository. {Online; accessed July 2007}.

INDEX TERMS

Primary Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
      D.2.2 Design Tools and Techniques

General Terms:
Measurement, Performance

Keywords:
heterogeneous networks, mobile telemedicine, mobility management, seamless handover, testbed, vehicular networks