Call Detail and Call Maintenance Records for Performance Measurement
description
Transcript of Call Detail and Call Maintenance Records for Performance Measurement
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
Text
TextText
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