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SIP-Based Voice Measurement Infrastructure. Cesar Marcondes UCLA. Motivation. Voice Measurements Predict Voice Quality Gateway Provisioning Assessment of Priority Voice over IP Calls in SIP.edu Debugging Misconfigured sites. Background/Issues.
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SIP-Based Voice Measurement Infrastructure Cesar Marcondes UCLA
Motivation • Voice Measurements • Predict Voice Quality • Gateway Provisioning • Assessment of Priority Voice over IP Calls in SIP.edu • Debugging Misconfigured sites
Background/Issues • We worked during the year 2003 in a similar idea in Brazilian Academic Network (RNP2) • Quality of voice can be determined through quantitative metrics mapping to Mean Opinion Score • MOS: Poor, Regular, Good, Excellent • And objectively calculated through • E-Model (ITU-T G.107 and ETSI ETR 250) • We can approach in two ways: • Active Quality Monitoring • Passive Quality Monitoring
Active monitoring - using remote answering machines (client/server model), generate call, not real ones, but "emulated". Assess network impairments. Passive monitoring of real calls - capture statistics from real calls, use sniffer near the "gateway" to detect VoIP flows and obtain the call leg RTP/RTCP Voice Measurement Models
Research Ideas • VoIP Scalable Measurement Infrastructure • Propose an automatic and robust architecture, implementation, support from SIP.edu (remote sites for active measurement), best practice cookbook (?) • Other research interests: • Assessment of VoIP calls over Wireless Hotspots in SIP-enabled campus • Design, Implementation and Assessment of TCP-rate based protocol (focus on VoIP as the payload) – the idea is obtain some “level of QoS” through dynamic changes in the cwind grow/decrease rate
Related Projects • H.323 Beacon (there could be necessary to implement a SIP version of this tool) • http://www.itecohio.org/beacon/ • Brazilian Academic Network (RNP) tools (basically they have an E-Model Implementation) • http://www.voip.nce.ufrj.br/ • Cisco/other vendors VoIP quality measurements tools in-built Cisco Works2000 VoiceManager