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Date: 29-01-99
Source: InformationWeek
Subject: True Test Of The Web
As the Web moves to the core of business, testing of applications and
infrastructure is more important than ever. Vendors are supplying the
tools.
By Alan Earls
Many companies doing business on the World Wide Web are one click away
from
disaster. With Web sites playing an increasingly important business
role,
it's essential that these systems deliver--whether their job is handling
product sales, distributing information, or linking up with partners'
systems.
Of course, gaining that assurance has been anything but easy. The task
of
testing
the performance of a Web application involves more than just running
a
functional test on the specific application, though that's important.
It's
also critical to ensure that all the supporting infrastructure works
under
varying pressures and conditions.
A growing number of vendors are addressing that difficult task with
testing
tools that range from freeware to complex bundles of products and services
that can cost $250,000 and up.
The high stakes of E-business mean it's no longer a question of whether
to
test but how. Consider the experiences of those companies that have
suffered high-profile site failures. In October 1997, with a market
rally
in process, E-Trade Securities Inc., the Palo Alto, Calif., pioneer
in
online stock trading, suffered a lengthy and embarrassing service outage
when trading volumes got too high for its system to handle. The company
survived the crisis and made several important technical and procedural
changes--but not before seriously damaging the confidence of its customers.
Similarly, a glitch during unscheduled maintenance at Amazon.com forced
the
site offline for several hours last year, prompting rumors that the
online
bookseller had gone out of business. Although Amazon.com wouldn't reveal
the cost of the site shutdown, outside analysts point out that daily
business on the Amazon.com site can be as high as $400,000. And in
order to
repair its customer relations, the company felt compelled to issue
discounts to those who claimed to have been unable to access the site
during the shutdown.
Troubled Debut
Worst of all might have been what happened to Egghead Software Inc.
The
very weekend that the retailer closed its last store as part of a much
publicized move to Web-based electronic product distribution, its
Egghead.com site went down for two days. Again, the company won't say
what
the glitch cost but outsiders note that Egghead probably has about
$1
million a week in online sales, making a botched debut a matter of
at least
a few hundred thousand dollars in lost revenue.
These three examples of Web-site failures are indicative of what companies
can expect as they put their most critical operations on the Web. Customers
have little tolerance for failure. So the questions for these Web-based
businesses are, who should test and how often?
New Venture, Or Old Rules?
Sandy Taylor, director of analyst services at the Software Productivity
Group in Natick, Mass., divides these risky new Web ventures into two
categories: companies that are developing a brand-new E-commerce Web
site
with built-from-the-ground-up functionality, and companies that are
simply
building Web functionality on top of their existing business rules
and
infrastructures. Taylor says companies in the first group are the ones
taking the biggest risks and therefore are most in need of testing.
Companies in the second category also must test their applications,
but
they at least have some existing metrics and experience to build upon.
Industry experts agree that Web testing is a good investment. Testing
in
general has achieved a lot more visibility lately, aided in part by
the
focus on the year 2000 remediation efforts. And, given the visibility
of
Web sites, it's fairly easy to argue for testing, says Liz Barnett,
a VP at
Giga Information Group. Barnett is especially bullish on the need to
test
sites involved in E-commerce. Although large intranets and extranets
can
face similar problems, she says, it's even more difficult for site
developers to anticipate load once an E-commerce site is opened to
the
general public. Doing business on the Web is like opening a traditional
store but not knowing whether it will be located in the middle of an
Iowa
cornfield or on New York's Fifth Avenue.
Furthermore, in the world of the Web, functional changes happen much
faster
and more frequently than in traditional mainframe environments, which
tend
to implement functional changes annually Client-server environments
tend to
implement functional changes on a monthly basis. But Web sites sometime
need to make daily changes, which can impact back-end infrastructure
and
system functionality.
Fortunately, the problems faced in the testing of Web applications are
not
entirely new. Indeed, the history of most site-testing tools goes back
to
the traditions of client-server computing. In fact, from a conceptual
standpoint, Web testing is much like client-server testing--but with
more
potential tiers and greater load variability. With a Web site, there
is no
way to predict with certainty how many users will hit a site at any
given
time. The Web environment has also introduced extreme heterogeneity
to the
support equation. Users may be accessing resources deep in a company's
infrastructure, and the IT department can't control what browser they
will
be using. The potential interactions between technologies are almost
limitless.
That's why some analysts prefer the term Web application testing to
the
more traditional functional and load testing. What matters is the
application seen by the users, not whether the Web site is having trouble
or the server is broken.
Three Functions Of App Testing
Within application testing there are three functional areas. The first
is
site testing: a structural test that looks to see whether there are
pages
that are inaccessible or whether popular features are unnecessarily
hard to
access. The second and third areas deal with whether the application
functions as designed, and whether that functionality survives at various
load levels and under a variety of scenarios.
Vendors offer each of these capabilities in a variety of flavors and
levels
of complexity. Some also offer integrated suites that provide life-cycle
testing.
The Web-testing market is young and fragmented. Prominent vendors include
Mercury Interactive and Segue Software, whose roots are in client-server
testing. RSW Software is a new subsidiary of hardware test giant Teradyne
and focuses exclusively on Web testing.
Mercury Interactive is generally regarded as the 800-pound gorilla of
the
business, with a mature and well-respected product line that includes
LoadRunner and Astra. Segue is an aggressive company offering tools
such as
SilkPerformer and a sophisticated scenario testing product called
LiveQuality (see story, p. 6A) that permits the generation of complex
interaction with large numbers of virtual users. Other players include
Compuware, Mindcraft, Rational Software, and RadView Software.
Web Watching
All of these products are currently being put through their paces in
the
real world. E-Trade for example, is using Mercury Interactive's LoadRunner.
After its aforementioned meltdown, E-Trade vowed to never go through
that
again, says Gary Kattge, director of quality assurance. E-Trade looks
back
at that experience as positive because the company learned a great
deal
from it. "Since that time, we've had much higher peaks, which we've
handled
without any problems," he says.
The meltdown forced E-Trade to adopt a proprietary stateless architecture,
which enables the E-Trade Web site to provide secure, reliable, and
almost
instantaneous service simultaneously to hundreds of thousands of users.
E-Trade, which rolled out its new and improved Web site this past summer
to
all 500,000 active accounts, experiences about 2.2 million page views
per
day, and expects further traffic increases as more noncustomers visit
the
site. During the quarter ended June 30, E-Trade processed an average
of
$1.5 billion in customer transactions per week.
In preparing for its public launch, E-Trade developed and installed
a
technology infrastructure able to handle massive traffic volumes. E-Trade's
Stateless Architecture system allows more than 1 million visitors to
use
the Web site simultaneously and permits as many as 150,000 customers
to
place orders at the same time. E-Trade says the system can be scaled
up to
handle even heavier loads.
Getting the system to that level of reliability was Kattge's job, and
testing was a big part of the project. Several testing-tool vendors
were in
the running initially, Kattge says, but based on functionality and
extensibility, E-Trade reduced the field quickly to one: Mercury Interactive.
Mercury Interactive's LoadRunner product lets E-Trade put hooks in the
test
code. This allows E-Trade personnel look in-depth at application response
time--right down to the SQL database-query level. The testing tool
has
given E-Trade the ability to calibrate and verify new system designs
and to
detect areas that might need additional tuning.
But LoadRunner's most critical role was in helping to measure response
times between various tiers, where the potential for serious errors
exists.
LoadRunner is used on an hourly basis as part of an alert system to
quickly
escalate any performance issues likely to require intervention.
Commonplace Tests
Even in the slightly slower-paced world of mutual funds, testing is
becoming commonplace. Mutual funds giant T. Rowe Price in Baltimore
is a
strong proponent of Web testing. T. Rowe Price recently implemented
its
first major Web site redesign. Time to market and availability were
critical to IT manager Tom Dietz, who has been looking at Web testing
issues at T. Rowe Price for more than two years. "We recognized Web-site
testing as a very important area," he says.
After evaluating testing tools, the company settled on Segue's
SilkPerformer, due in part to its regression testing, Web functional
testing, and load-testing capabilities, Dietz says.
First Call Corp. in Boston is another organization with a Web site that
gets put to the test. First Call keeps broker notes, research documents,
earnings, and buy-sell recommendations flowing to its Wall Street
professionals via its Web site. The company's roots in online services
predate the Web, but when it came time to embrace Internet delivery,
they
selected Segue's SilkPerformer. "We were interested in testing costs,
the
ability to simulate user loads, and memory footprints per virtual user,"
says First Call IT manager James O'Keefe.
FirstCall also wanted a good scripting language. While it was important
to
demonstrate site viability through load and stress testing, it was
equally
critical that the scripting tool be able to show that real information
was
being delivered. SilkPerformer let the First Call team monitor specific
deliverables like HTML code, or a copyright symbol that could verify
that
the site was delivering as intended.
Of course, not every mission-critical site is seen by the public. Paul
Roach, a senior quality assurance specialist in the Richardson, Texas,
office of Northern Telecom Ltd., got his exposure to Web-site testing
during the requirements phase of Nortel's global intranet development
project.
Nortel's intranet consists of many applications deployed across a global
intranet--an environment that demands frequent testing of the Web servers
and applications. Scalability, robustness, and a rich feature set were
on
Nortel's shopping list.
In one instance, Roach helped deploy an employee-satisfaction survey
that
would be accessible by 70,000 employees worldwide. Other sites required
testing of functions as diverse as financial accounting, sales, and
marketing. Dropping the ball with employees, even on a satisfaction
survey,
can be just as serious as offending paying customers, he says.
Cost Conscious
Choosing a product and determining what to spend are perhaps the greatest
challenges to the newcomer to Web testing. CBS.com has opted for a
freeware
program. Compared with the tasks of supporting real-time stock trading
or
other "heavy duty" E-commerce activities, Michael Skorski's job might
seem
easy. Director of technology for CBS Net Media, Skorski makes sure
www.cbs.com is up and running when the network's viewers come looking
for
program information and news. And the old adage about the short shelf
life
of news applies to Web news sites--specially when there's scandal in
the
air. "We did four times our normal traffic and an order of magnitude
more
hits and page requests when Kenneth Starr's report hit," says Skorski.
Skorski and CBS have been testing their site extensively, which may
account
for the fact that it survived the onslaught of Starr gazers with only
minor
problems.
That's attributed in part to CBS's use of Webstone, a freeware product
now
maintained and distributed by Mindcraft. "There are limitations on
what it
can do," Skorski says, "but the price is right and the product is now
part
of our testing regime."
Commercial testing tools have more bells and whistles, Skorski says,
but do
not necessarily produce more useful information. His biggest challenge
with
testing is to simulate the complex infrastructure of www.cbs.com.
Karl Van Neste, a software system architect at the College Board in
Reston,
Va., warns buyers to beware. "Test managers need to continually review
the
products and new capabilities available on the market." Van Neste has
been
using a product recently introduced by a small company called RadView
Software. Van Neste says he first looked at Mercury Interactive's
LoadRunner but that RadView's product had what he felt was comparable
functionality for a small fraction of the price.
Indeed, new entrants keep cropping up almost daily, making it likely
that
increased capability and decreased price will be the order of the day.
IT
managers will also see a variety of service offerings for those shops
that
don't want to experience the cost and learning curve of Web testing
tools.
Illustration by Dennis Harms
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