Ensuring Quality in the Contact Center Joseph Dumont Product Manager Contact Center Services Empirix, Inc.

Abstract: This presentation will focus on assuring IP telephony voice quality in the contact center and the enterprise. The presenters will address concepts such as active call monitoring and multilayer monitoring, and discuss how these strategies can be used to determine when a failure has occurred or is about to occur in an IP telephony network. The conversation will include a discussion of how performance management reporting can be used to assure that service level objectives are met and how recurring failures can be identified and prevented in real-time. Proactive multi-channel testing and monitoring of contact center and communication solutions and their role in improving performance and customer experience will also be addressed. This is a shared session with IQ Services. You will each have time for a 20 minute presentation, with a 5 minute Q&A at the end.

How do I know I have a problem? –Is the voice quality on my network acceptable? –Is everything working properly? What’s wrong & how do I fix it? –Is increased traffic effecting voice quality? –Is something broken? What is it? –Did something change that effects voice quality? –How do I get to the source of the problem? How do I detect trends and know when my next problem will occur? –Are things trending toward degrading quality? –Do I have recurring problems? Every Monday morning? Some other event? Assuring IPT Voice Quality

Lifecycle Assurance Initial Baseline New Business Initiatives (ie: CTI, Speech Rec)

Identifying a Problem

What Could Possibly Go Wrong? User Acoustic echo; handset speaker to microphone Hybrid echo; impedance mismatching (handset or local loop) Distortion; hybrid analog-to-digital conversion and compression Network Network faults Over capacity Circuit noise; switching External noise; crosstalk Signaling protocol mis-matches Transcoding; compression Echo suppression Delay (Latency); packet, speech Jitter; packet, speech Out of order packets Loss of packets Duplicate packets

IPT Infrastructure Management Management System UC App Servers http access SNMP Monitoring CDRs/CMRs Backend Systems Gateway Stats PSTN

Troubleshooting

Passive Monitoring What is it? Insert Network Probe –Locate probes around the network –Probes “listen” to all calls and report call quality Solution types –Protocol Analyzers –VoIP specific monitoring probes Pros See “real” calls, trace problems to specific endpoints Possible to monitor every call Reactive - must wait for a “bad” call to detect a problem Difficult troubleshooting - hard to determine what caused the problem Expensive – need lots of probes to cover large networks Cons

Active Monitoring What is it? Place monitoring calls and measure call statistics –On and off the network Pros Simulates a real call, follows actual call path Accurate measurements Proactive – detect problems early Extensive testing, IVRs, CTI, etc. Cannot see every call Takes resources ­Bandwidth ­Directory Numbers Cons

Infrastructure Monitoring What is it? Collect call statistics from switches and gateways –CDRs, CMRs –Phone Stats –RTCP collectors Pros Inexpensive Collect information as seen by the infrastructure – consistent reporting Reactive - must wait for calls to all locations Difficult to determine what caused the problem Limited diagnostic capabilities Cons

Troubleshooting What do I need to test and monitor? Infrastructure –Switch / Media Gateway handoffs –Media Gateway echo insertion / loss –Agent “Presence” or registrations –Voice quality over WAN / Toll-bypass links –Conference Bridge Link Voice Quality Application –IP IVR embedded CTI –Speech Voice activity detection (VAD) impact on Speech enabled applications –DTMF Acceptance parameters (In-band vs. Out-of-band signaling)

Performance Management

Performance Reporting What Are the Trends? Voice quality getting worse? Recurring problems? Poor VQ correlated with other factors?

Summary Identify a problem –Passive Monitoring –Active Monitoring Troubleshoot to find the cause of the problem Performance management –Find trends –Identify trouble periods

Supplementary Slides

Ways to Detect Problems Users complain Customers complain CEO complains Much Better Not Good Test before deployment Passive monitoring Gather information from the infrastructure Active monitoring

Measuring Voice Quality Specified by ITU-T P.830 in 1996 Range of results: 1 to 5 Absolute Category Rating (ACR) is: ­5 is excellent ­4 is good ­3 is fair ­2 is poor ­1 is bad Mean Opinion Score (MOS) Individuals provide an ACR score Resultant MOS is an average of the scores Panel of Human Listeners Expensive to set up Cumbersome maintenance Inconsistent results Not practical or scalable for live networks or frequent regression testing Problems MOS = ( )/4 = 3.75

IP Voice Quality Factors Impacting Quality GatewayGateway/Phone Lost Packets CODEC -introduces some distortion Jitter Late packets are discarded by jitter buffer Round trip delay

Passive, Non-reference-Based E-model GatewayGateway/Phone Lost Packets CODEC -introduces some distortion Jitter Late packets are discarded by jitter buffer Round trip delay E-model R Factor

Active, Reference-based PESQ FFT Perceptually weighted Objective score Test (speech) file Sent thru’ network 500 MIPS processor PESQ algorithm (ITU P.862) based on and replaces previous (ITU P.861 PSQM, BT PAMS) algorithms VoIP Service Voice Quality Tester