Assessing network readiness for IP telephony

Networked multimedia applications require stringent real-time QoS guarantees. Successful deployment of such applications closely depends on the performance of the underlying data network. The characteristics and the QoS requirements of these applications are different from traditional data applications. Hence, prior to deployment it is necessary to evaluate a network from a multimedia perspective. In this paper, we focus on IP Telephony and describe a framework for providing tools for IP Telephony readiness evaluation. This framework can be easily generalized to other multimedia applications. Our approach injects synthesized voice traffic and measures perceived end-to-end quality. We present a novel idea of relating voice quality metrics to the performance of data network devices. Following the proposed framework, we developed a prototype tool to evaluate a network and to identify problems, if any, prior to IP Telephony deployment. Our tool automatically discovers the topology of a given network, and collects and integrates network device performance and voice quality metrics. We describe the architecture of our tool and provide sample outputs from a network consisting of 129 devices.

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