Call Detail and Call Maintenance Records for Performance Measurement

Call Detail Records - CDR: info about the endpoints and control/routing of a call Used for billing Call Management Record - CMR: info about the quality of the streamed audio of a call May have more than one CMR per CDR Both CDR and CMR are needed Documented by Cisco

Background and Motivation 1998 Voice over IP with Selsius now > 12,000 ethernet VoIP instruments Integrated Backbone Architecture ATM moving to routed ethernet Star of routers - 2 levels 8 routers at UP

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Service Level for Voice Performance SL developed to support voice One way latency < 25ms Loss < 0.001% packets Jitter < 5ms

SL continued Model voice traffic and measure it Modeled by UDP streams at 85 kbps Measured loss, latency and jitter Van Jacobson talk/paper about pathchar - MSRI using iperf 1.7

QoS for Voice Implemented Expedited Forwarding To protect the voice traffic in 6500/7600 Cisco router Compared with best effort vs EF for voice

While at a meeting While at a meeting with Cisco about a separate problem, I stumbled upon the fact that the Cisco IP Phones track network statistics

The phones report loss, latency, jitter, packets and octets sent and received. which can be recorded in CDR/CMR CMR

So, the next step Establish thresholds intra system phone-to-phone Inter-system phone-to-someone-else’s-stuff

This is still a work in progress Questions Thank you