Agilent Measurement Journal - Issue 3 - 2007 - (Page 31)

In the case of VoIP, R-factor scores and mean opinion score (MOS) are also available. MOS is a measurement of audio quality with scores ranging from 1 to 5 and values below 3.0 indicating poor voice quality. Because voice is a real-time service, it must be delivered with minimal delays and reproduced with a constant bit stream on the egress network or endpoint (150 ms end-to-end delay is a common recommendation). A view of the MPEG2 transport stream allows network engineers to perform detailed real-time analysis of video streams present in the network (Figure 2). For example, IPTV multicast or VoD unicast streams contain critical information useful in troubleshooting video impairments. Also, ETSI TR 101-290 events can be analyzed with conﬁgurable thresholds for reporting. PCR jitter accuracy and errors are also reported to determine synchronization errors. Media delivery index (MDI) analysis allows engineers to determine buffer size issues and lost packets that directly affect the quality of video. Agilent’s video MOS degradation function shows the impact of network impairments on video quality and provides an indication of video degradation. All of these events are calculated and presented per stream, including performance analysis per elementary stream. In addition, a viewer is available to visualize the video quality of a speciﬁc stream, allowing a direct visual assessment of subscriber QoE. For video signaling analysis, the video control view keeps track of subscribers changing channels. Whenever this occurs, a series of IGMP leave and join commands are sent to the network. The J6900A records leaves, joins and zap/response times per subscriber, allowing detailed analysis of QoE. Conclusion The triple-play mix of voice, data and video brings with it new levels of complexity that can adversely affect subscriber QoE. The ability to ensure a positive experience can beneﬁt from test solutions that enable end-to-end design, deployment, monitoring and maintenance of triple-play networks. One such solution is the Agilent J6900A triple play analyzer, which addresses network interoperability, IP network performance, voice and video service quality and QoE. Easily operable without advanced expertise or programming skills, it enables engineers to quickly identify QoErelated problems by providing test results for key parameters of IP telephony, IPTV and VoD network performance. Figure 2. MPEG transport stream analysis Agilent Measurement Journal 31

Table of Contents Feed for the Digital Edition of Agilent Measurement Journal - Issue 3 - 2007

Applying Ingenuity to the Measurement of Emerging Technologies Contents Emerging Innovations Department Delivering Bigger Benefits by Optimizing Customer Workflows Measuring Material Properties at the Nanoscale Utilizing In Situ Atomic Force Microscopy in Life Science, Pharmaceutical and other Bio-Related Applications WiMAX™: Plotting a New Path to Global Mobility Addressing the Triple Complexity of Triple-Play Networks What Next for Mobile Telephony? Exploring the Inner Workings of Tire-Pressure Monitoring Systems Developing, Assessing and Applying a High-Resolution Thin-Film Magnetic Probe Making Accurate Settling-Time Measurements Using a Vector Network Analyzer Applying Metabolomics Methods to the Study of Bacterial Leaf Blight in Rice Plants Measuring Stream Dynamics with Fiber Optics survey

Agilent Measurement Journal - Issue 3 - 2007

For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.