As I said in my Request for Clarification, I went to an wireless
telecom expert to answer your question. We pooled our knowledge of
telecommunications and innkeeping to assess your situation.
Let me start out by pointing out some of the negatives for going
wireless. First and foremost, while wireless is becoming more popular,
it is far from ubiquitous so a certain number of your clientele will
not be able to use the network. Nearly all laptops have modem and/or
RJ45 Ethernet built in. The second thing to consider is that the range
of these systems are relatively short and you still need to power
them, which means potentially running wires. The last thing to be
concerned with is vandalism. As Im sure youre aware, anything that
is exposed is subject to tugging, poking and in some cases just being
ripped out. And in your case, it sounds like the only possible
installation will involve exposed base stations.
Keeping all of this in mind, wireless provides a great way to reduce
the amount of wiring that needs to be done, allows the user to move
about in the room(s), and is pretty easy to set up yourself.
The Wi-Fi devices operate in the Instrument and Scientific
Measurement Band (ISM) at around 2.5GHz. This is the same frequency
that most new cordless phones operate at. Propagation (the manner in
which radio moves through the environment) generally gets worse the
higher the frequency but that isnt the real problem with Wi-Fi. The
problem with this technology is that, because its unlicensed, the FCC
limits the transmission power allowed for these devices, further
limiting the usable distance. Im certain from your question that you
understand the concept of the base station versus the end points, so I
wont bother to explain it. Something that you should be aware of,
however, is that the newer base station technologies allow wireless
bridging, so you may not need to cable them separately to an Ethernet
connection, thereby reducing your installation costs.
The building you describe is problematic, but not impossible. Your
type of construction will limit the distance a user can be from a base
station to between 35 and 50 feet with omni-directional antenna. Im
sure the concrete floors and ceilings are reinforced with rebar that
is potentially grounded. This could be a problem, but as its only two
floors, Im going to assume that strategic placement of the base
station on floor one will adequately cover the second story. This
means that the installation can be limited to the first floor of each
building, which will also help manage the installation costs.
From your description, the layout of the building is approximated by a
square. I have assumed from your clarifications that there are no
hallways, so the base stations will have to be put in the rooms, which
is not the best choice. An exterior installation would be problematic
because of difficulties sighting poles outside in the courtyard. On
the upside, it will be easy to power them since AC outlets are
accessible. Mounting the base stations securely under a table, or
behind an armoire to keep them out of sight would help minimize the
risk of damage or theft.
Because we have to get through concrete block and concrete surfaces,
there are no hallways to use as a waveguide and base station placement
may be random, I would not count on getting more than a 35 foot radius
from each base station. Placing units at each corner will cover
between 4 and 6 rooms (vertically and horizontally). Linear coverage
(not on a corner) will not yield such good results since youll have
to pass through at least one block wall and whatever else is in the
way. If you assume 4 rooms per base station, this should assure
coverage. That means youll need 10 base stations to cover all of the
rooms (20 for both buildings). Im also guessing that there will be
enough leakage to cover much of the courtyard too but it will be
spotty. Its possible that you will be able to get away with a couple
less, but I would not count on it.
Another problem you face is sharing this network between buildings. My
recommendation would be to use two DSL lines or two cable modems and
let the network provider deal with the problem. However, this will
result in two monthly fees. There are other options including point to
point Wi-Fi that you can put on the top of the buildings. Some of
these systems claim ten mile ranges (overkill for your application)
and cost several thousand dollars. Another option is to bridge the two
buildings with a conduit and some high-end Category 5 cable. Watch the
Ethernet cabling rules though. The standard warns against any legs
over about 350 feet or so. To get around this, you can use a router at
the end of the building to isolate the second one. Each base station
is a router and some have an extra Ethernet port to daisy chain
devices because of these limitations. These types of limits are why
geography is so important in these applications.
This link is chock full of information on Ethernet:
Ethernet: The Definitive Guide
by Charles Spurgeon
as is this website:
by Jason John Schwarz
I suspect that the reason youre going wireless is so you dont have
to know all of this, but the reality is that the wireless portion of
these systems is to simply extend the end of a cable - not replace it.
You still have to mind the design rules.
To improve the do it yourself odds, try to find equipment that
offers wireless bridging or youll have to cable each base station to
wired Ethernet (then physical connections per building). Most of the
newer gear will do both 802.11b and the faster 802.11g. They also have
external antennas or jacks and do wireless Ethernet relaying so, with
luck, youll only have to hard cable one of the base stations and the
rest will act as repeaters. Try to find a unit with an extra Ethernet
jack on them so, in the probable case that the customer doesnt have
built in wireless, they can simply plug in. (Im still worried about
the base stations sprouting legs, though.)
To address your request for an estimate of the cost of this project,
these base stations run around $250 apiece. This results in a hardware
cost of $2500 dollars per building. If you buy one high speed
connection per building and have the service company install it,
youll avoid the conduit-between-building problem and get the
connection to the hub room with the installation price of the
service. If not, thats an additional expense. Note that routers and
Ethernet line drivers are cheap so the big expense here is running the
wire between the buildings. I would try wiring from an extra Ethernet
jack on the last base station and see if it works. Finally, youll
have to physically install the base stations, which you can do
yourself for zero cost. Im sure that youll have other costs too,
like miscellaneous cables and possibly some external antennas to
improve propagation, so I would include a 30% buffer in my estimate.
If you had to cable all ten base stations, I would estimate an
additional cost of two days labor at $40 per hour ($320) per day and
$300 for cable and perhaps a repeater or two. This would add roughly
$1000 per building. Again, try the wireless bridging option first!
If I were doing this, I would buy two base stations initially and run
some tests in the building with a wi-fi equipped laptop to refine my
estimates before proceeding. Put the base stations in different spots
in the rooms and check the power levels in the rooms on either side,
above and outside. Most of these systems come with a utility for
gauging performance levels as you move around.
I believe you asked for other things you should be aware of with
wireless, and there are a few things you should know. Security is
always an issue. Turning on WEP (Wireless Encryption Protocol) will
slow down the network a bit, but you should make this standard. You
will need to dole out a network name and password to your guests, and
change it occasionally. This means youll have to do some minimal
administration. This many transmitters will probably put you in the
category of a hot spot, so keep the security up or youll have
strange people in your parking lot surfing the web on your nickel.
As far as traffic goes, todays estimates will not be valid tomorrow
but take heart that, if you start with one line, you can always split
the network at some point. So for example, you might want to start
with one high speed line and, as you see more folks using the system
(or complaining about it), you can split the network and administrate
each building autonomously. You estimated 15 to 20 users at a time.
Most network studies Ive done assumed a 10% concurrency figure which
would imply that maybe three users would be trying to retrieve
information at the exact same time. I dont think this will introduce
any noticeable delays. If you get a lot of business people and theyre
using your rooms as an office, you should start out with two networks.
To sum up, dont be afraid to do-it- yourself and experiment a little
first. Im sure that youll have a few problems but nothing that you
cant solve by tweaking things a bit. Good luck.
Should you have questions on any of the above, jmanly, please do not
hesitate to ask for a clarification.
Consultation with resident expert