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802.11 B and G standard - what is the range?

Hi guys

so i finished my intership of 1year and now i am back in university, and guess what my networks assignment is to make a report to a company that wants to set up a wireless network.

anyway the office is supposedly a 200 X 200 metters

i got it all planned in my mind and have started writing the report

the problem is i can't find a source to quote me the sort of range 802.11 b or g standard is suppose to operate.

i know u guys all going to say

well it depends, i know it depends in millions of things, but there must be somewhere out there a document posted from IEEE or CISCO that say the average range in a average office building

i am kind of tiered from looking in google and IEEE.

i don't have access to all IEEE papers only to some that my university subscribe

in any of this my question is

Does any one know a website or a book or a white paper or preferably a journal which i can quote the range of 802.11 standard

thank you so much !!

I know some one here will know this stuff

----------------------------------------------

this is my assignment

Task Description

The Head Office of the Smith Fabric Company is located in a four-story building. Each floor consists of an open plan office measuring 200mx200m. 24 staff are located on each floor who are supported by stand-alone PCs, which desperately need upgrading. The Company is planning to renew all the PCs and to set up a LAN to link them together. It is also the Company's intention to connect the LAN to the Internet. To gain access to the Internet, the Company has just signed a contract with an Internet Service Provider and has received a Class C IP address. It is the Company's intention to run a web site at this site to publicise the Company's products to the outside world.

The Managing Director has been advised to use wireless network for the new LAN for its flexibility. However, security is a major concern of the managing director and the network should include appropriate security mechanisms.

As a consultant, you are required to:

1. Design a wireless network for the Company, incorporating any new devices required.

2. Allocate appropriate IP addresses to the relevant devices.

3. Draw a diagram for the network.

4. Provide cost analysis for the devices required.

You may make any assumptions, but they should be well clarified.

Write a report as a consultant to propose your solution with full justification. The report should not exceed two A4 sides, excluding diagrams and appendices. You are advised to use as many diagrams as necessary to support your proposal.

4 REPLIES
Hall of Fame Super Red

Re: 802.11 B and G standard - what is the range?

Hi David,

As you have noted "it depends", so I won't go into all the variables. Here are some averages that are based on the Antenna type used.

For example:

AIR-ANT5959

Approximate Indoor Range at 54 Mbps 88 ft (27 m)

Approximate Indoor Range at 6 Mbps 295 ft (90 m)

-------------------------------------------------

AIR-ANT1728

Approximate Indoor Range at 54 Mbps 114 ft (35 m)

Approximate Indoor Range at 6 Mbps 379 ft (116 m)

-------------------------------------------------

AIR-ANT4941

Approximate Indoor Range at 54 Mbps 90 ft (27 m)

Approximate Indoor Range at 6 Mbps 300 ft (91 m)

From this good guide;

Cisco Aironet 2.4 GHz and 5 GHz Antennas and Accessories

http://www.cisco.com/en/US/products/hw/wireless/ps469/products_data_sheet09186a008022b11b.html

Hope this helps!

Rob

Please remember to rate helpful posts.....

Green

Re: 802.11 B and G standard - what is the range?

While the question has been asked and answered (and very well) ... being that I'm sort of an ol' timey networking sort, and feeling scrappy ... let me give you a different approach for your consideration.

1) Don't do a wide-scale wireless LAN in this scenario

2) Use a wired LAN for the fixed PCs, use wireless for conference rooms or other management gathering places (assumes managers have laptops), maybe some sort of Guest access that is partitioned from the common corporate network.

While current wireless (i.e., EAP / 802.1x -based) is much more secure than previous generations (i.e., WEP, MAC filters, etc), the physical security of a wired LAN is still generally better and easier to "defend" (you can put cabling in conduits / raceways, and terminte it behind closed & locked doors ).

Cabling is faster and more efficient, can more easily be upgraded to newer speeds (i.e., GigE, 10GigE) and is easier to partition the traffic (VLANs / broadcast domains)

I can go on for while, but I think you get the idea.

SO(!) make the following assumptions ("anything is valid if you support it with the proper assumptions"):

The person that WANTS (note: not "Needs")the wireless network doesn't understand any of the above ( and assciated problems) They want it because they think it's cool, neat, exciting technology (and it is, just not for "everywhere") .... and once you explain it to them, they will see the light and go cabled general network with wireless supporting specific functions (conferences, guests, consultants, etc)

Costs may be higher initially (predominantly labor), but the cabled network will likely have better "legs" and adapt better to future technological advances.

Even if / when wireless can handle the same traffic loads (wireless is a shared medium, like a hub) at the same speeds, chances are you'll need a cabled backbone architecture to connect all that wireless stuff you need to distribute around the office (still a valid part of the investment).

Use POE-capable switches, so future migration / expansion of the wireless infrastructure is supported (also IP Phones in addition to the POE-capable APs)

Service devices / web servers / hardware firewalls / network servers / addressing all remain the same for either wired or wireless (you'd have to be a raving idiot to put servers / shared resources on wireless without a *real* good reason).

Anyway, you get the idea. Break out of the box, don't take the "use wireless" bait ... tell 'em like it is, even though educators aren't likely to be well-grounded in reality.

The "Class C address" block is a ringer: The internal network would likely be / oughta be / don't be stupid an RFC1918 address block (10.x.x.x, 172.16-31.x.x, 192.168.0-255.x), with some smaller block of "Class C" public addresses reserved for inbound Web access (and maybe a couple for outbound PAT) defined on the external interface(s) of your firewall.

If you really have to come up with a Bill of Materials, don't forget things like UPS, racks, jumpers, *** AIR CONDITIONING FOR THE DATA CENTER (duh)*** and the **** CLOSETS*** that will have the access-level devices ...

A power audit and possible installation / upgrade for the data center and closets (how many closets have you seen with a couple 20A circuits? )...

Money for service contracts (maintenance, software updates for router / switch / ap / Call Manager, IP phones ... whatever)

And (this is a margin builder) routine "check up" visits (it keeps your face fresh so the customer won't forget you and you get to tell him of the new, neat, and exciting technology that he can't live without .. it's a "keep the salesman fed, and he will keep you fed" kind of program.

Like I said, there's more ... if you need more let us know. This is just my take on the information you've presented.

Good Luck

Scott

New Member

Re: 802.11 B and G standard - what is the range?

Whats up Scott, looks like you want to do the assignment for me hehe AWESOME stuff.

In my industrial placement i had to design and deploy a new 100 people office over 2 floors with WLan and Lan and MAN to our main offices, i had guys helping me out since i was just a student in a intern placement making sure i was doing the right stuff, but that gave me so much experience, like the stuff u talking about audits, budgeting for labour and Air Conditioning.

for sure you must have done this a few times, cause you seem to know this real well.

thank for all your help.

btw give me your opinion on this Scott

look at the picture, the floor is 200X200

if i have the cables coming though the middle of the building, it is still more then 100m (standard) from the middle to a desk in the corner, what do u suggest in terms of hardware per floor, since there is 24 people per floor, when it comes to physical layout

Hall of Fame Super Red

Re: 802.11 B and G standard - what is the range?

Well Scott, you've outdone yourself this time!!Really excellent answer. 5 points, and well worth it.

Take care,

Rob

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