Call Detail and Call Maintenance Records for Performance Measurement

"Call Detail Records - CDR"

	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

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QoS for Voice

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

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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

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"The phones report loss,"

	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-elseÕs-stuff

"This is still a work..."

	This is still a work in progress
	Questions
	Thank you