Mobile Networks and Applications

, Volume 11, Issue 4, pp 625–640

Signal threshold adaptation for vertical handoff in heterogeneous wireless networks

  • Ahmed H. Zahran
  • Ben Liang
  • Aladdin Saleh


The convergence of heterogeneous wireless access technologies has been envisioned to characterize the next generation wireless networks. In such converged systems, the seamless and efficient handoff between different access technologies (vertical handoff) is essential and remains a challenging problem. The heterogeneous co-existence of access technologies with largely different characteristics results in handoff asymmetry that differs from the traditional intra-network handoff (horizontal handoff) problem. In the case where one network is preferred, the vertical handoff decision should be carefully executed, based on the wireless channel state, network layer characteristics, as well as application requirements. In this paper, we study the performance of vertical handoff using the integration of 3G cellular and wireless local area networks as an example. In particular, we investigate the effect of an application-based signal strength threshold on an adaptive preferred-network lifetime-based handoff strategy, in terms of the signalling load, available bandwidth, and packet delay for an inter-network roaming mobile. We present an analytical framework to evaluate the converged system performance, which is validated by computer simulation. We show how the proposed analytical model can be used to provide design guidelines for the optimization of vertical handoff in the next generation integrated wireless networks.


Heterogeneous wireless networks Seamless integration Vertical handoff Application signal strength threshold 3G cellular Wireless LAN 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    R. Berezdivin, R. Breinig and R. Topp, Next-generation wireless communications concepts and technologies, IEEE Comm. Mag. 40(3) (March 2002) 108–116.Google Scholar
  2. 2.
    M.M. Buddhikot, G. Chandranmenon, S. Han, Y.W. Lee, S. Miller and L. Salgarelli, Integration of 802.11 and third generation wireless data networks, in: Proc. of IEEE INFOCOM, San Francisco, US, (Apr. 2003) pp. 503–512.Google Scholar
  3. 3.
    A.K. Salkintzis, C. Fors and R. Pazhyannur, WLAN-GPRS integration for next-generation mobile data networks, IEEE Wireless Comm. 9(5) (Oct. 2002) 112–124.Google Scholar
  4. 4.
    I.F. Akyildiz, J. McNair, J. Ho, H. Uzunalioglu and W. Wang, Mobility management in current and future communications networks, IEEE Network 12(4) (July/Aug. 1998) 39–49.Google Scholar
  5. 5.
    B. Liang and Z.J. Haas, Predictive distance-based mobility management for multi-dimensional pcs networks, IEEE/ACM Transactions on Networking 11(5) (Oct. 2003) 718–732.Google Scholar
  6. 6.
    J. Makela, M. Ylianttila and K. Pahlavan, Handoff decision in multi-service networks, in: Proc. of 11th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC’00), vol. 1, London, UK (Sep. 2000) pp. 655–659.Google Scholar
  7. 7.
    G.P. Pollini, Trends in handover design, IEEE Comm. Mag. 34(3) (March 1996) 82–90.Google Scholar
  8. 8.
    A. Hatami, P. Krishnamurthy, K. Pahlavan, M. Ylianttila, J. Makela and R. Pichna, Analytical framework for handoff in non-homogeneous mobile data networks, in: Proc. of (PIMRC’99), Osaka, Japan (Sep. 1999) pp. 760–764.Google Scholar
  9. 9.
    M. Ylianttila, M. Pande, J. Makela and P. Mahonen, Optimization scheme for mobile users performing vertical hand-offs between IEEE 802.11 and GPRS/EDGE networks, in: Proc. of IEEE Global Telecommunications Conference GLOECOM’01, vol. 6, San Antonio, Texas, USA (Nov. 2001) pp. 3439–3443.Google Scholar
  10. 10.
    M. Ylianttila, J. Makela and P. Mahonen, Supporting resource allocation with vertical handoffs in multiple radio network environment, in: Proc. of IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC’02), Lisbon, Portugal (Sep. 2002) pp. 64–68.Google Scholar
  11. 11.
    H. Park, S. Yoon, T. Kim, J. Park, M. Do and J. Lee, Vertical handoff procedure and algorithm between IEEE802.11 WLAN and CDMA cellular network. Proc. CDMA Int’l Conf., (2002) pp. 103–112.Google Scholar
  12. 12.
    M. Ylianttila, R. Pichna, J. Vallstram, J. Makela, A. Zahedi, P. Krishnamurthy, and K. Pahlavan, Handoff procedure for heterogeneous wireless networks, in: Proc. of IEEE Global Telecommunications Conference (GLOBECOM’99) 5 (Dec. 1999) pp. 2783–2787.Google Scholar
  13. 13.
    K. Pahlavan, P. Krishnamurthy, A. Hatami, M. Ylianttila, J.P. Makela, R. Pichna and J. Vallstron, Handoff in hybrid mobile data networks, IEEE Comm. Mag 7(4) (Apr. 2000) 34–47.Google Scholar
  14. 14.
    A. Majlesi and B.H. Khalaj, An adaptive fuzzy logic based handoff algorithm for hybrid networks, in: Proc. of 6th International Conference on Signal Processing 2 (Aug. 2002) pp. 1223–1228.Google Scholar
  15. 15.
    H. Wang, R.H. Katz and J. Giese, Policy-enabled handoffs across heterogeneous wireless networks, in: Proc. of the Second IEEE Workshop on Mobile Computer Systems and Applications, New Orleans, Louisiana (Feb. 1999) p. 51.Google Scholar
  16. 16.
    F. Zhu and J. McNair, Optimizations for vertical handoff decision algorithms, in: Proc. of IEEE Wireless Communications and Networking Conference (WCNC) 2 (March 2004) 867–872.Google Scholar
  17. 17.
    L. Chen, T. Sun, B. Chen, V. Rajendran and M. Gerla, A smart decision model for vertical handoff, The 4th Int’l Workshop on Wireless Internet and Reconfigurability (ANWIRE’04) (May 2004).Google Scholar
  18. 18.
    M.M. Buddhikot, G. Chandranmenon, S. Han, Y. Lee, S. Miller and L. Salgarelli, Design and implementation of a WLAN/CDMA2000 interworking architecture, IEEE Commun. Mag. 41(11) (Nov. 2003) 90–100.Google Scholar
  19. 19.
    T.S. Rappaport, Wireless Communications: Principles and Practice (Prentice Hall, July 1999).Google Scholar
  20. 20.
    K. Murakami, O. Haase, J. Shin and T. LaPorta, Mobility management alternatives for migration to mobile internet session-based services, IEEE Journal on Selected Areas in Communi. 22(5) (June 2004) 834–848.Google Scholar
  21. 21.
    C. Guo, Z. Guo, Q. Zhang and W. Zhu, A seamless and proactive end-to-end mobility solution for roaming across heterogeneous wireless networks, IEEE Journal on Selected Areas in Communi. 22(5) (Jun. 2004) 834–848.Google Scholar
  22. 22.
    C. Tepedelenlioglu and G. Giannakis, On velocity estimation and correlation properties of narrow-band mobile communication channels, IEEE Trans. on Vehicular Technology 50(4) (July 2001) 1039–1052.Google Scholar
  23. 23.
    Q. Zhang, C. Guo, Z. Guo and W. Zhu, Efficient mobility management for vertical handoff between WWAN and WLAN, IEEE Commun. Mag. 41(11) (Nov. 2003) 102–108.Google Scholar
  24. 24.
    N. Zhang and J.M. Holtzman, Analysis of handoff algorithms using both absolute and relative measurements, IEEE Transactions on Vehicular Technology 45(1) (Feb. 1996) 174–179.Google Scholar
  25. 25.
    A. Papoulis and S. Pillai, Probability, Random Variables and Stochastic Processes, 4th ed. (McGraw-Hill, 2002).Google Scholar
  26. 26.
    G. Bolch, S. Greiner, H. de Meer and K.S. Trivedi, Queuing networks and Markov Chains: Modeling and Performance Evaluation with Computer Science Applications, 2nd ed. (Wiley, Aug. 1998).Google Scholar
  27. 27.
    IEEE Standard, Part 11: Wireless LAN medium access control (MAC) and physical layer (PHY) specifications, IEEE, 1999.Google Scholar
  28. 28.
    3GPP2 Standard, CDMA2000 wireless ip network standard: Packet data mobility and resource management, 3GPP2 X.S0011-003-C v1.0, Sep. 2003.Google Scholar
  29. 29.
    N. Tripathi, J. Reed and H. VanLandingham, Handoff in cellular systems, IEEE Personal Commun. 5(6) (Dec. 1998) 26–37.Google Scholar

Copyright information

© Springer Science + Business Media, LLC 2006

Authors and Affiliations

  • Ahmed H. Zahran
    • 1
  • Ben Liang
    • 1
  • Aladdin Saleh
    • 2
  1. 1.Department of Electrical and Computer EngineeringUniversity of TorontoTorontoCanada
  2. 2.Bell Canada/Wireless TechnologyMississaugaCanada

Personalised recommendations