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Security broker for multimedia wireless local area networks

Se Hyun Park, University of Massachusetts Amherst


Multimedia Wireless Local Area Networks (MWLANs) supporting various applications require secure communication for both multimedia and data applications. With the increased popularity of network and internet applications, the need for protecting information has emerged among all levels of users. This security issue is much more emphasized in wireless communication scenarios. To minimize the deterioration of multimedia applications performance, the design of security mechanisms for WLANs must consider the WLAN unique characteristics. In addition, malicious attacks can occur in many more locations in the WLAN environment than in a wired network. Therefore, security support functions need to be designed accordingly. In this dissertation, we employ the Security Broker that uses one or more security mechanisms to support reliable end-to-end secure multimedia applications. The introduced Security Broker includes the following novel security mechanisms: Authentication and Privacy Protocols, Re-Authentication Protocol and Inline Security Layer. The Authentication and Privacy Protocol can be applied within the PCF (Point Coordination Function) of IEEE 802.11 standard. With the integration of polling based PCF and the use of the session code, we achieve an effective authentication and privacy mechanism. The goal of Re-Authentication Protocol is to provide continuous security support during a specific session. The proposed Re-Authentication Protocol which includes a key exchange procedure has a low computational complexity. Our new Inline Security Layer, is proposed and implemented to support bulk encryption for MWLANs. Instead of using dedicated cryptography hardware, the proposed security layer considers the WLAN characteristics. The proposed and implemented layer has the following advantages: (1) is less expensive to use and implement than dedicated hardware, and (2) is more flexible for upgrades. We have implemented the Security Broker and pursued extensive experimentation. We set up the test platform with two computers that communicated via WLAN adapters. In cases CPU and memory resources are sufficient, we observed no degradation in the multimedia applications quality of service in terms of throughput and delay. Future generation of computers will provide us with abundance in CPU and memory resources. Therefore, we foresee software encryption as a viable approach for wireless LANs that support multimedia applications and communication.

Subject Area

Electrical engineering|Computer science

Recommended Citation

Park, Se Hyun, "Security broker for multimedia wireless local area networks" (1999). Doctoral Dissertations Available from Proquest. AAI9920638.