January 23-26, 2007• Ft. Lauderdale, Florida

Achieving, Monitoring and Maintaining A High Quality of Experience

Benjamin Ellis, Psytechnics

January 23-26, 2007• Ft. Lauderdale, Florida

QoE for IP – The Problem Space• QoE is not just about IP network statistics• QoE for telephony applications depends on:

– IP-transport performance• Extent IP network statistics impact on voice quality• ITU-T P.564

– Telephony performance • ITU-T P.561 parameters

– Echo– Delay– Noise Level– Speech Level

• ITU-T P.562, CCI (Call Clarity Index) combines P.561 parameters to give two-way conversational performance of the channel

• Voice waveform quality

– Conversational measures• ITU-T P.563

• Combined assessment of all aspects is required

January 23-26, 2007• Ft. Lauderdale, Florida

Taxonomy of VoIP Call Quality

Transport• IP Bearer• Packet Loss• Jitter• Out of order packets

Payload• Media Stream• Speech Activity• Speech Level• Noise

Conversational• Echo• Delay• Noise

CallSignalling

CallSignalling

January 23-26, 2007• Ft. Lauderdale, Florida

VoIP Quality Challenges

DeviceImpairments

Voice System

Impairments

TransportImpairments

IP Impairments

Ethernet

switch

Firewall Router SBC Router Media

Gateway

TDM

switch

Voice

switch

January 23-26, 2007• Ft. Lauderdale, Florida

High Quality of Experience Requires

• Visibility into– Network (connectivity and transport issues)– IP QoS (packet loss and other impairments)– Voice Infrastructure (all elements)

• Across the Lifecycle– Design– Pre-deployment – Roll-out – Management – Optimization

• Integrated Management– Fault Management– Performance Management

January 23-26, 2007• Ft. Lauderdale, Florida

Quality of Experience• More Satisfied Users

– Quality differentiated services– Meaningful SLAs

• Actionable Metrics• Thresholds and Reports

– Delivering essential competitive quality– Customer retention, reduced churn– Service re-use

• More Efficient Networks– Directed maintenance– Targeted investment– Efficient operation– Billing – billable quality

• More Effective Support– Fewer support calls and truck rolls– Faster problem resolution– Pro-active fault management

January 23-26, 2007• Ft. Lauderdale, Florida

Thank You

• Questions