Transcript Quality of Service – State of the Market

Quality of Service – State of the Market
Alan Percy
Director of Business Development
AudioCodes, Inc.
[email protected]
Booth #822
AudioCodes – A VoIP Leader
 13 Years of Operation Focusing on VoIP Media
Gateway & Media Server Technology
 Field proven technology: Over 12 Million
Channels shipped to over 100 Countries
 Enabling the VoIP leading OEM’s and TEM’s
 Key originator of ITU G.723.1 standard for VoIP
 Leader in Innovation and Density of VoIP
Solutions
 Financially strong and stable
Background
10
8
in millions
 Customer demand
is building
 VoBB carriers are
proliferating
 What will
differentiate the
carriers?
Consumer VoIP Subscribers
6
4
2
0
'03
'04
'05
'06
Year
'07
'08
Source: In-Stat
New Carriers, New Challenges
A few years ago, we equipment providers thought we had
this figured out.
Then:
 Private networks
 Intra-Enterprise
 Carefully controlled
(over-engineered)
networks
New Carriers, New Challenges
Today: New Frontier
 Depending on existing broadband



Cable
DSL
Fixed wireless
 New Wireless Services




3G
WiMax
WiFi
SAT
What have we learned?
You can’t always control the network

To make the business model work, you sometimes need to
leverage the existing infrastructure
What have we learned?
The last mile is the hardest mile!
What have we learned?
 Murphy’s law is true!
(Poor voice quality will only affect the CEO during an
important investor call)
 Poor voice quality will get you kicked out
 Huge variation in voice quality between equipment
vendors
(Especially when network conditions are not “ideal”)
Is voice quality important?
“Voice Quality is the most sensitive
issue for business customers”
Greg Schreiber, VP of Product Development - Vaspian
What affects voice quality?
Choosing the Right Coder
Measuring Voice Quality
 Listening Speech Quality Scores

Perceptual Evaluation of Speech Quality (PESQ)
• Automated using ITU recommendation P.862
• Range of voice coders
• Range of network impairments
– 0 – 5% Packet Loss
– Up to 20 msec Jitter
– Up to 100 msec additional delay
 Conversational Aspects

Ability to deal with background noise,
double speak and echo
ETSI Speech Quality Test Event





Sponsored by ETSI - Done by HEAD Acoustics Labs
Has been held several times over the past three years
VoIP equipment testing in controlled conditions
Receive an objective and comparative analysis
The tests include all conversational aspects, including:




Speech sound quality
Echo measurements
Double Talk performance
Transmission quality in the presence of background noise
 Anonymous - Only your results are identified
ETSI Test Setup
Packet
MONITOR
Gateway
NISTNet
IP
IP
Gateway
IP
Packet Loss
Delay
E1
E1
PBX
ISDN DSS1
ISDN DSS1
HEAD acoustics
Test System ACQUA
Input
Output
ETSI results Summary

Six conversational and six listening tests

Ten gateways participated in 3rd SQTE

The results for each gateway are summarized in a Pie Chart with a slice per
each category

The performance in each category was represented by the radius of the
slice and by a color code



Red – the amount of which the results were under the
requirement
Yellow – result was below the requirement if accompanied with
red or OK if no red
Green – result was above the requirement
ETSI Test Result for 10 Gateways
P1
P2
P3
P4
P5
P6
P7
P8
P9
P10
Measuring Quality – RTCP XR
Real Time Control Protocol – Extended Reports
 Embedded measurement tool
 Measuring Quality During the Call



Packet Loss
Delay
Signal Quality …
 Call Quality – MOS and “R” Factor
 Reported in RTCP, SDP or via SNMP
Improving Voice Quality
Techniques vendors use to maximize quality:
 Dynamic Jitter Buffer

Adjusting to ever-changing network conditions
 Packet loss concealment





All coders, including G.711
Echo cancellation algorithms
“Double Speak”
VAD and CNG algorithms
Extensive field and lab testing
Thanks
Alan Percy
Director of Business Development
AudioCodes, Inc.
[email protected]
Booth #822
Come and meet us
at the Keynote!
Thursday @ 5:15