era of wireless LANs has finally set in. The technology
is now mature enough to be put to business or commercial
use. by Milind Kamat
though wireless LANs are currently more expensive to
deploy than their wired counterparts, there are several
instances in which a wireless LAN is a better alternative.
Here are some examples.
Quick network deployment: Today long-distance fiber
backbones are becoming more widespread. The issue is
how to distribute this bandwidth easily to the end users,
who are distributed across geographies. To some extent,
this is being done through mobile service providers
(BPL, Airtel, etc.), and through satellite. But a more
practical solution is wireless LAN technologies like
the 802.11b or 802.11a standards, which have the advantage
of speed of installation and commissioning. After the
September 11 attacks, companies are finding it imperative
to quickly set up LAN and Internet connections, for
alternative offices and sites.
Roaming connectivity: With the proliferation of mobile
hand phones, the user mindset is shifting towards "always
on connections." This is very prominent with top
decision makers, especially in the services and hospitality
segment. Here, there are two important aspects: one
is movement of the objects and movement of the user.
Here are two instances to exemplify this. With courier/freight
forwarding companies, packages entering and leaving
a location need to be tracked. A notebook user on campus
wants access to server or network resources, as he moves
about. For both these applications, wireless LANs are
probably the best alternative.
Public & fun places: There are places like airports,
hotels, clubs, etc. where a large number of people gather.
They either have a lot of spare time, as they wait for
their flights in airport waiting lounges, or come together
in clubs. In both situations, information accessible
through the Internet is a clear requirement, for which
a wireless LAN is the ideal solution.
Difficulty in cable installation: The installation of
cables could be hampered for various reasons like getting
permission from authorities, non-feasibility of installation
in old buildings and ancient monuments, etc. So wireless
LAN makes sense here.
High cost of cable installation: In some places the
effective cost of cable installation is very high. This
may be due to loss of business during that period, or
the finishing work needed after that. This is particularly
applicable in places like hospitals and hotels.
Secured connection: Wire or fiber is a physical medium
and can get damaged. So VSATs are used for long distances.
For shorter distances of 10-30 Km, wireless LAN can
be a good alternative. This area has become more relevant
especially after disaster management gained importance.
LOOK BEFORE YOU LEAP
Before handing over the task to the network designer,
the CIO/CTO must really examine basic needs versus inflated
requirements. It isn't surprising to see how one wants
a desktop PC with minimum memory of 64 MB, and on the
other hand be contended with 16-32 KB on a handheld
computer. In one way 100 Mbps may not be sufficient,
and on the other hand we may be comfortable with 10-20
Kbps of Internet access bandwidth. In fact, one should
seriously reconsider the following issues:
Is LAN bandwidth getting used efficiently?
Is it necessary to "buy & maintain"
the entire infrastructure?
Can we use the virtual infrastructure maintained by
After we have found the right answers, we can move further.
Moving from wired to wireless has some unforeseen advantages.
One is that, given the choice between mobility and bandwidth,
the natural human tendency is to go for mobility.
The second advantage is that wireless devices are much
more personal. From a budgeting point of view, this
would mean that the demand for handhelds, PDAs, notebooks
etc. would increase compared to full-fledged desktops.
Now such devices are typically owned by the individual
rather than the company. So what wireless does is reduce
the need for companies to directly fund the purchase
of end-user devices. Companies may initially have to
subsidize the purchase of wireless devices by their
employees, but in the long run, there will be substantial
Another interesting aspect is that temporary workers
and business partners can share the wireless fabric,
thus extending the reach of the enterprise applications,
giving greater control to the enterprise. Yet another
benefit is that wireless networks promote thin-client
based applications rather than fat-client applications,
making it easier to develop and maintain such applications.
This further reduces IT budgets. All these factors together
can help reduce IT budgets in the long term, even though
wireless networks may seem more expensive than their
VALUE PROPOSITION FOR WIRELESS
To take an analogy, wired versus wireless is like bus
versus car. Large bandwidth on the wire is analogous
to high capacity of the bus. Bandwidth increase is analogous
to increase in speed and frequency of the bus. But can
a bus service ever match the convenience of a car? A
car gives you the freedom of anytime anywhere mobility,
as does wireless technology.
As it stands today, wireless products cannot be compared
with the price and efficiency presented by the wired/fiber
networks. Hence there has to be a distinct value proposition
attached to the wireless solution.
Presently, there are two popular options: 802.11b (11
Mbps shared) and 802.11a (55 Mbps shared). But the advantages
presented by high bandwidth (802.11a), are limited to
the smaller distance covered. So one has to make a choice:
How far vs. How fast?
There seems to be an attractive option of dual-band
products supporting both 802.11b and 802.11a standards.
one has to be extremely careful, as this advantage can
be very misleading. For two reasons: the distances covered
may totally change as you switch from one standard to
the other. Consider this scenario: all users may be
connected at 55 Mbps (802.11a), and one mobile user
may connect at 11 Mbps (802.11b). In such a scenario,
the entire network speed will fall back to 802.11b.
This may lead to total change in design of the wireless
network or may demand heavier investments today. It
may be a better option to switch over to another standard
whenever needed. Frequency approvals in 802.11a frequency
band need to be checked carefully.
Site Planning Utilities: Reputed vendors provide site
planning aids along with their products. These utilities
help in evaluating signal strengths and the bandwidth
available at a specific location. A good wireless network
can be designed with this information.
Amplifiers & Antenna: To cover larger distances,
amplifiers and special antenna support is needed. Single-vendor
support for all such accessories eliminates some of
the intricate issues.
Power over Ethernet: To cover a specific area or to
maintain the deco, the Access Point/Bridges need to
be placed at a specific location. Now, there may not
be power connection available in the vicinity. In such
cases, DC power can be fed thru the CAT-5 Ethernet cable.
Devices providing such support are called Power Injectors.
Access points/bridges accepting such power over Ethernet
should be carefully considered.
The time for wireless LANs has come. The technology
is now mature enough to be put to business or commercial
use. Technical aids are available to ensure that wireless
LANs can be implemented effectively and securely.
business productivity benefits, the IT department can
also benefit by structural improvements in its applications
The writer is Country Manager-India,
SMC Networks. Send your comments and feedback to firstname.lastname@example.org