VoIP Telephony Growth is Still Limited by Issues of Reliability and Audio Clarity, Latest Keynote Study Reports

SAN MATEO, CA., — May 21, 2008 — Keynote
Competitive Research, the industry analysis group of Keynote Systems
(Nasdaq: KEYN), the global leader in mobile and Internet test &
measurement solutions for continuously improving the online experience,
today announced the results of its Industry Study Series of Voice Service Providers. The study looked at reliability and performance of leading VoIP, PacketCable and local wireline services.

Keynote’s competitive research study provides valuable data and
insight that help VoIP providers of both managed networks and unmanaged
networks overcome the quality barriers separating them from traditional
local wireline phone service. The study compares the relative
performance over a single month of a local wireline service (AT&T)
with seven broadband VoIP providers (AT&T CallVantage, EarthLink
trueVoice, Lingo, Packet8, Verizon VoiceWing, Vonage, and Vonics
Digital) and two cable voice service providers (Time Warner Digital
Phone and Comcast Digital Voice) from calls made from residential
locations in New York and San Francisco.

While VoIP’s market share continues to grow, a recent study* showed
that the number of traditional fixed line customers continued to drop
sharply during 2007 with Verizon and AT&T both reporting declines
of around 10% in residential wireline accounts. The growth in VoIP was
a major contributor to this decline, in particular cable VoIP, with
subscriber growth rates around 75%. VoIP reliability and audio clarity
remain important factors that will influence the long-term customer
retention potential of these new market players. “The service level
performance of traditional wireline voice service continues to
outperform the VoIP competition. Cable companies using managed networks
are rapidly closing the gap and will continue to make this an exciting
market to watch,” remarked Ben Rushlo, senior manager with Keynote’s
competitive research group.

VoIP Service Provider Study, Wave 5 Competitive Research Results

Keynote’s study reveals that while most voice service offerings from
the cable companies and VoIP service providers trail traditional
wireline service in quality, some service providers are highly
competitive.

Keynote’s new study of voice service quality uncovered the following observations:

• Consumers are more likely to experience merely tolerable, rather than completely satisfactory audio delay on VoIP calls.
• One VoIP service provider studied had no calls measuring a MOS of
  4.0 or better, a key threshold for end user satisfaction; the best a
  consumer on this service can hope for is merely tolerable sounding
  audio.
• One VoIP provider experienced audio delay of more than 150 ms for
  every call placed, increasing the likelihood of conversational
  disruption for end users.
• One VoIP provider required six seconds more than other VoIP providers to connect calls after dialing.
• There were large quality gaps between VoIP providers on unmanaged networks and other service providers.

These findings are of great significance to VoIP providers who are
under increasing market pressure to understand and prevent high rates
of customer attrition and churn in a rapidly changing market. To find
out more information about purchasing the complete Keynote voice
competitive research study including detailed rankings, please visit: www.keynote.com/keynote_competitive_research/industry_studies/voice.html

About Keynote Voice Perspective

Voice service providers can leverage the competitive insight provided through Keynote’s Voice Perspective® for Service Providers for on-going real time monitoring of voice quality from representative
locations to improve their call performance in target markets.
Combining Keynote’s voice monitoring services and competitive insights
with internal network monitoring tools will allow providers to adopt an
outbound focus and assure a quality experience for the end user.
Keynote can design an ongoing voice quality measurement and monitoring
implementation for multiple markets including multiple competitors.
Service providers can leverage Keynote's independent assessment to
align their resources and infrastructure investments with customer
acquisition and retention goals.

In addition, Keynote can provide custom analysis to help align
operations teams with customer experience enhancement goals. To learn
more about Voice Perspective for Service Providers view: www.keynote.com/products/voip_and_streaming/voip_quality/voice_perspective_sp.html

Availability and Pricing for Wave 5 Study and Voice Perspective

Keynote’s Wave 5 study is available for purchase from Keynote,
includes detailed results, custom analysis of the data and all raw
measurement data. For information, please visit: www.keynote.com/keynote_competitive_research/industry_studies/voice.html

Keynote’s Voice Perspective for Service Providers is available immediately. Pricing is customized based on the number of
cities, providers and network carriers to be included in the ongoing
measurements.

^* 2008 – USA – Telecoms, Wireless and Broadband, Report Buyer: http://www.reportbuyer.com

About Keynote

Keynote Systems (Nasdaq “KEYN”) is the global leader in on-demand
test & measurement solutions for continuously improving the online
experience. As an independent and trusted third-party, Keynote provides
IT and marketing executives with an unbiased view into their Internet
services from around the world. For over a decade, Keynote has been
providing measurement data and testing capabilities that allow
companies to understand and improve their customer’s online and mobile
experience. Keynote has four test and measurement businesses: Web
performance, mobile quality, streaming & VoIP, and customer
experience/UX. In addition, Keynote’s industry analysis group called
Keynote Competitive Research publishes proprietary studies measuring
customer experience and service levels across a wide range of
industries.

Known as The Mobile and Internet Performance Authority™, Keynote has
a market-leading infrastructure of 2,400 measurement computers and
mobile devices in over 240 locations around the world. Keynote also
maintains one of the most representative panels of online users
consisting of 160,000 consumers. Keynote’s on-demand, hassle-free
infrastructure allows businesses to access services they need, when
they need them to pinpoint and fix mobile quality and Internet problems
before they impact customers.

Keynote helps over 2,600 corporate customers become “the best of the best” by helping them improve online business
performance and mobile communications quality. Keynote’s customers represent top Internet and mobile companies including
American Express, BP, Caterpillar, Dell, Disney, eBay, ESPN Mobile, E*TRADE, Expedia, FedEx, Microsoft, SonyEricsson, Sprint,
T-Mobile, Verizon and Vodafone.

Keynote Systems, Inc. is headquartered in San Mateo, California and can be reached at www.keynote.com or by phone in the U.S. at (650) 403-2400.

Keynote, The Internet Performance Authority, Perspective and Customer Experience Rankings are registered trademarks and
The Mobile and Internet Performance Authority and True Experience are trademarks of Keynote Systems, Inc. Other trademarks
are the property of their respective owners. © 2007 Keynote Systems, Inc.