Question

UO provides temporary office space in cities around the country. They have

a standard office layout that is a single floor with outside dimensions of 150 feet wide by 150 feet

long. The interior is drywall offices. They have a switched 100Mb

wired LAN but want to add

WLAN as well.

Data rates have been shown to slow dramatically when the distance from a laptop

to the wireless access point (radius of circle) exceeds 25 feet

.

a.

How many access points would you recommend and where would they be placed?

b.

Draw the office and show where the access points would be located.

c.

Show coverage for each access point with a circle, and label the channels (1, 6,

Answer 1

We are required to evaluate the number of access points required and the placements of those access points in a Ubiquitous Office (UO). Here we would be needing four access points since four Aps will be able to serve the entire office of 150x150. The Aps have to be placed 50 feet away from each other in the middle four corners of the office forming a square of 150x150 sq feet.

• 1000Base-T uses Ethernet cards
• It uses copper wires for communication
• The other name for this standard is IEEE 802.3 ab
• It is of the magnitude of Gigabits
• The maximum length that can be supported a single segment is 100 meters
• It can transmit up to 1000 Mega Bits Per Second and hence the name 1000 Base T
• The base is restricted to Ethernet signals only
• It uses Category 5 twisted pairs without shielding
• Our building inner area is 150*150 = 22,500 square feet or 45.72*45.72=2090.32 square meters (sq.mr.) approximately (2090.3184 square meters rounded to 2090.32 sq. mr.)
• Area of the office space = 2090.32 square meters = 22,500 square feet.
• A single access point can support between 1600 to 4900 square feet (sq. ft.) depending up on the wall thickness, the gain boost by the antenna, amount of power settings made etc – we are having dry walls
• Factors like The cement or brick walls used in the civil engineering construction, amount of traffic density all contributes to the coverage by a single access point
• hence these factors will affect the number of access points we would need
• we would need between 5 to 14 access points for 22,500 square feet
• But if we buy the 802.11 enterprise grade wireless LAN access points, we can vover this area with just between 4 to 7 access points as they have more coverage capacity of between 4900 square feet to 9900 square feet per access point
• Data support can be provided up to 20 to 30 clients per access point
• but voice will reduce it to 10 to 15 clients per access point