The fat PC and the thin client continue to slug it out for control
of the corporate desktop. Lindsay Clark assesses the two
adversaries
Ever since businesses started to network PCs in large numbers
they have been aware of one thing: PCs were not designed to be
networked in large numbers. The mounting costs of owning PCs
sparked a vociferous 'religious war' among IT suppliers over
whether to go for fat PC clients or thin client/server-based
computing.
That war is now more or less defunct. Windows 2000 includes
support for thin clients as standard. All the major PC
manufacturers, except Dell, now also supply thin clients. The
advent of the Internet has made many
applicationsserver-based,whilethe prospect of supporting multiple
Wap phones and wireless personal digital assistants (PDAs) further
clouds the once-simpledichotomy of thin versus fat.
While suppliers fought and then made up over the thin-client
debate, some users have been quietly reaping the benefits. When
retail supplier Littlewoods looked at providing PC applications to
stores throughout the UK, it saw support issues as being onerous.
To avoid having to send a member of the support team hundreds of
miles every time a PC broke down, the company optedfor
theWindows-basedterminal model - and has never looked back.
"Generally, it's been a big success," says Andy Dawson,
infrastructure manager at Littlewoods. "It has delivered everything
we expected it to deliver in terms of reduced support overhead. We
have not been able to quantify that, but we have managed the
environment within our existing team and extended theservice to an
extra 300 users."
However, Dawson says there are limitswithhis Citrix-based
thin-client
implementation. "We have to be carefulnotto become a victim of
our own success," he says. "People often ask us to put another
application on the system. We feel it's important to keep within
our niche. We have to keep control of the environment - a power
user could lock up the resource of a whole server and prevent 20
other users from logging on."
Before Littlewoods implements a new application across its
network, the application has to be analysed to ensure it adheres to
the Microsoft Terminal Server guidelines, says Dawson. Support
staff must also check applications for memory leakage, which can
bring down a whole server.
Littlewoods has 350 terminals at stores around the country each
available to multiple users. E-mail, Microsoft Word and Excel are
offered as standard, while PowerPoint is restricted because it is
power hungry. There are also line-of-business applications that are
browser based. Littlewoods uses Windows NT 4.0 Terminal
ServerEditionandCitrix MetaFrame load balancing software. Although
Littlewoods is testing Windows 2000, which includes load balancing
for servers supporting thin clients, the company is unlikely to
abandon Citrix. "We believe a network manages bandwidth better than
Windows Terminal Service," Dawson says.
This is typical of successful Windows-based terminal
implementations, according to Eric Grayson, European marketing
director at NCD, which manufactures thin-client devices. "The
retail market is very big," he says. "So is banking and financial
services - often these companies have a history of server-based
applications and mainframe environments."
Andy Brown, analyst with IDC, says that with most of the major
suppliers now providing thin-clients the model is gaining in
popularity, particularly in vertical markets such as banking and
finance. However, Brown says that the continuing growth in PC sales
shows that the thin-client market will remain relatively small.
"Most research has shown that the idea of thin clients being the
next big thing never materialised, but they have become a
significant niche player."
However, the argument for server-based computing as a means of
reducing the massive costs of supporting PCs still remains,
according to Mark Margevicius, senior research analyst with the
GartnerGroup. He estimates that 40% to 45% of the cost of owning a
PC is associated with end users not doing what is right for them or
their organisation.
"The thin-client model takes away that variability from the
client," he says. "Not only is the total cost of ownership reduced
from the end-user point of view, you get to put a cheaper device on
the client location."
However, Margevicius points out that companies looking for
reduced capital expenditure tend to forget that saving with
hardware is limited. What you take off the desktop you have to put
on the server - the exact demand on the server and the network will
depend on the application.
Another area in which users expect costs to fall is software
licensing, he says. "A number of people still think that just
because applications are running on the server, licensing costs
will go down. In fact, these will remain the same, and there may be
additional costs if you chose to license MetaFrame or WinFrame from
Citrix."
The licensing model offered by software suppliers varies. While
Citrix offers a licensing model based on the maximum number of
users that can concurrently access the server application,
Microsoft demands a client access licence (CAL) for every user that
can access an application and operating environment. This means
that users must have a Windows NT Workstation CAL for every
thin-client user. Although this is offered as a discount, the
workstation operating system is not even in use.
Margevicius says that users may have the ability to negotiate
deals with software suppliers such as Oracle or SAP for concurrent
licensing. This is not likely to happen if you are dealing with
Microsoft software. Windows product manager Mark Tennant confirms
that Microsoft licences for business users would remain on a
client-access basis, whether the software is served to a thin
client, PC or browser-based device.
Although PC sales far outstrip those of thin clients, this does
not imply that server-based computing is unpopular. The ability to
lock down PCs to prevent end users loading software, together with
a dramatic fall in PC prices, has resulted in PCs becoming the most
common client-to -view server-based applications.
"PCs are much cheaper than they were when this idea first came
about,"Margevicius points out. "The thin clients have ended up
costing around £100 less than a PC. You can configure a PC to look
like a thin client or to work on its own. PCs are providing users
with greater flexibility."
Dell, the only major PC supplier not to offer thin-clients, has
no intention of moving into the market. Client systems marketing
manger James Griffith says PCs will remain the company's core
product for at least the next five years. He believes that PCs
offer users flexibility - an option to go with server computing or
not - without being locked into particular desktop hardware.
Citrix, the company that originated software to allow multi-user
Windows access, estimates that 80% of its installations are running
on PCs rather than thin-client terminals.
As a guide, users should check four things before moving to
server-based computing says Margevicius. First, can the application
be adapted to the server? Most can, but for technical reasons, some
cannot. The server and network must have 100% availability - all
users stop working when the system crashes. The network must also
be pervasive - if it cannot be accessed from some locations, you
cannot standardise the model. Lastly, power-hungry and mobile
computing is not suited to thin clients.
Margevicius says the thin-client model is most likely to be
successfully deployed in pockets within companies, rather than as a
company-wide standard. Some organisations are very unlikely to take
to it at all.
"Try putting thin clients in a university where there is large
number of knowledge workers, who need a lot of flexibility," he
says. "It [server-based computing] won't workwithremotesales
forces, or field engineers either.Generally,the model does not suit
peopledoingindividual,unpredictable work that is unique from one
day to the next."
Once users and suppliers free their minds of the thin versus fat
debate, it becomes obvious that server-based computing has already
taken off in a massive way, says Margevicius. "Really, the ultimate
thin model is the Internet, were everything comes through the
browser and all you download are applets. People do not think about
it like that. This is where the real growth has been and will
continue to be.
"Moving forward, this model will continue to grow along with the
pervasiveness of networks. New server-based applications will
become available on all sorts of devices, including PDAs and cell
phones - these will all be thin-clients. Over time there will be
many alternative devices to which applications are presented," he
adds.
But this also presents a problem. Although the thin-client
concept was intended to resolve the horrendous management problems
of supporting PC networks, the explosion in the number and variety
of client devices accessing Internet applications will create
difficulties of its own.
The big problem is going to be synchronising information across
these devices, and across disparate server infrastructures.
According to Margevicius, "Two client types can be difficult
enough, but four or five different clients, that's a problem. The
job of synchronisation is going to be horrendous. The IT shop is
going to be expected to take control of it and it is going to be a
difficult job."
Screen test
The GartnerGroup's Guide to going thin
Mark Margevicius, senior research analyst with the GartnerGroup,
offers four factors to consider when choosing whether to adopt
server-based computing or to stick with more conventional PC
networks.
Make sure the application behaves properly
Some software never can be configured to network computing
applications. Issues such as the addressing of system hardware may
be written into the application, for example, accessing disk
drives. Rewriting the application may be too complex to
consider.
Server and network availability
You need to have 100% availability on your network and server.
All of your users are totally dependent on it - if it goes down
they cannot work. A couple of years ago Oracle CEO Larry Ellison
was demonstrating network computers and suffered an embarrassing
outage. For business, it can be more disastrous, so redundancy
should be built-in according to business risk.
Network coverage
Users must be able to have access to high-quality network
infrastructure throughout your organisation. The cost of upgrading
or expanding the network will be a factor in your decision.
Type of usage
If you have a call centre where orders are taken in a single,
fixed location , then thin-client s can be a good idea. If you have
a travelling salesforce, thin clients are inappropriate. For
example, you cannot use a thin-client workstation while flying
30,000-feet above ground.
Thin client vs PC - the story so far
The problems in supporting a PC network are legendary. Although
PCs are supposed to be built on an open architecture, the truth is
they conceale all sorts of differences in hardware and software,
which makes managing large corporate networks a nightmare.
Only in the past few years has distributing software from a
central location been possible, meaning IT support staff would not
need to take laborious and costly journeys around every company
location to give users new applications. In addition, PCs attracted
the attention of the end-user enthusiast who could load his or her
own software on to systems, adding viruses and instability.
By the mid-1990s, so disgruntled were IT departments at this
onerous work, that suppliers who had remained out of the PC
business, namely Sun and Oracle, sensed an opportunity. Supported
by research company Gartner Group's concept of the total cost of
ownership, they launched the concept of the Network Computer - a
highly managed thin-client that allows centralised software
distribution and could prevent end-user tampering. Most of the
processing would be done on the client, but the software
environment would be configured and controlled from the server.
This vision of a PC alternative received a great deal of attention,
but sales were limited.
The main reason was that users had already invested in PC
infrastructures and Windows-based applications and were not
prepared to rip it all out. Although Java-based NCs are used in
some specific line-of-business application, they did not replace
PCs. However, the thin-client idea did not die.
In 1993, Citrix shipped WinView, software that would allow
multiple users to access Windows running on a server. This was
followed by WinFrame that contained technology that Microsoft
licensed from Citrix and used in its Windows NT4.0 Terminal Server
Edition. Now users don't have to buy a different version of
Windows, as the capability to serve applications to multiple
clients, whether they are PC or thin client, is built into Windows
2000.