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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 - PowerPoint PPT Presentation
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•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
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