Performance analysis of voice/data integration on X.25 protocol

Abstract

The integration of voice with data in a common packet switching network offers significant benefits; high utilization and reduced system cost through the sharing of switching and transmission resources, and enhanced services for users who desire access to both voice and data communications. In this thesis work, packet voice communication through the X.25 packet-switched network is studied. Different performance requirements between voice and data require some modification in the X.25 protocol structure. We show that the feasibility of the introduction of an additional packet voice service to an existing X.25 packet-switched data network justifies itself as a reasonable approach to the integrated services digital network (ISDN). Also, we introduce a packet voice flow control concept based on the bounded flow time. Flow control on voice packets requires somewhat different features as compared with data packets due to its real time service requirement after voice call set-up. This flow control strategy achieves better delay performance at the cost of some packet loss, which can be made as small as desired by adjusting the bound on flow time.