Author: Chen, Haitao
Title: A secure fast handoff protocol for inter-WLAN roaming in 3G-WLAN interworking networks
Degree: M.Sc.
Year: 2010
Subject: Hong Kong Polytechnic University -- Dissertations
Wireless communication systems -- Security measures.
Wireless LANs -- Security measures.
Mobile communication systems -- Security measures.
Department: Department of Computing
Pages: viii, 61 leaves : ill. (chiefly col.) ; 30 cm.
Language: English
Abstract: The 3rd generation (3G) mobile communication networks and Wireless LAN (WLAN) interworking attracts more and more attention because 3G network and WLANs complement each other in terms of coverage, bandwidth and cost. The 3G Partnership Project (3GPP) adopts Extensible Authentication Protocol Authentication and Key Agreement (EAP-AKA) for authentication in 3G-WLAN heterogeneous networks. By adopting EAP-AKA, authentication in the two different types of networks can share a single credential-USIM (Universal Subscriber Identity Module). However, the EAP-AKA protocol uses the 3G subscriber's IMSI (International Mobile Subscriber Identity) as the username for authentication and this leads to the possibility of revealing users' privacy to the attackers, especially in the scenario where the mobile user roams among multiple WLAN access points (APs). Another problem which can occur is, when the mobile user roams among the WLAN APs, a full EAP-AKA authentication is required to perform during the handoff, and this leads to a significant latency. There are some protocols and algorithms to deal with the problem of handoff latency. But the approaches either add two much network burden or the handoff delay is still high, and some of the approaches can only applied to only a subnet while not applicable for inter-subnet. This research is to investigate the issue of how to reduce handoff latency by avoiding full authentication while at the same time guarantee the user's privacy. We propose a fast handoff scheme to use handoff key instead of the credentials in the USIM card to authenticate the mobile user when the user roams between WLAN APs in a 3G-WLAN heterogeneous network environment. We have designed a protocol to generate the fast handoff key material for authentication and distribute to the potential target AP prior to the handoffs. The key material is encrypted by IBE (Identity-Based Encryption) using asymmetric cryptograph. Different from the existing approaches and protocols, in our fast handoff scheme, the mobile user acts as the distributor for the current AP to carry the key material to the target AP. This greatly reduces the round trip time for the target AP to poll the key material from the previous AP as what happened in the traditional distribution system. We have built a testbed to simulate EAP-AKA authentication so that a full EAP-AKA authentication is performed to allow the mobile node to connect to a WLAN AP before the handoff. We have also implemented the proposed protocol in our testbed. And we have evaluated the protocol by using simulations and running tests on the testbed. The result shows that the proposed fast handoff scheme can reduce the handoff delay greatly and complies to IEEE 802.11i security requirements.
Rights: All rights reserved
Access: restricted access

Files in This Item:
File Description SizeFormat 
b23526695.pdfFor All Users (off-campus access for PolyU Staff & Students only)2.19 MBAdobe PDFView/Open


Copyright Undertaking

As a bona fide Library user, I declare that:

  1. I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
  2. I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
  3. I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.

By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.

Show full item record

Please use this identifier to cite or link to this item: https://theses.lib.polyu.edu.hk/handle/200/5635