1. Convenient - Allow users to access network resources from any convenient location

2. Mobility - Allow users to access the internet from outside the working environment

3. Productivity - Can maintain a nearly constant affiliation with their desired network as they move from place to place.

4. Deployment

5. Expandability - Able to serve a sudden surge of clients with the existing equipment

6. Cost

1. Security - Possibility of being compromised by adversary

2. Range - Typical range for a common 802.11 g network with standard equipment is on the order of tens of metres.

3. Reliability - Subject to a wide variety of interference and complex propagation effects that is beyond control

4. Speed - Decreases when number of clients increase

5. Slower compared to LAN

Transmission Impairments

1. Attenuation

   • Loss of signal strength due to travel distance, noise, physical surroundings.

   • Transmission range increases, attenuation increases.

   • More noise, more attenuation.

   • Barriers distort transmission.

2. Multipath distortion

   • Radio signal has more than one path between receiver and transmitter.

     • other radio frequency signals reflect or refract.

     • Data sent is corrupted.

     • Decreasing signal amplitude - reflected waves arrive is out of phase.

3. Noise

   • Presence of unwanted signals (other WiFi networks, microwave oven, Bluetooth connection) in the radio frequency spectrum of Wi-Fi.

     • • Delay in transmitting data.

       • Low performance.

Security

1. Expose of data even when transmitting through protected Wireless LANs.

   • Third party users can easily encrypt password and traffic.

Transmission Delay

1. Propagation Delay

• Arise due to the signal requires some time to travel across a medium

• Propagation delay is proportional to the distance spanned

2. Access Delay

• Set of devices that share a medium must contend for access

3. Switching Delay

• A device in the network must compute a next-hop for each packet before transmitting

4. Queuing Delay

• A router gathers the packet bits, stores them in memory, selects a next hop, and then waits until the packet can be sent before transmitting

5. Server Delay

• The time taken for a server to review and compute a request and to send a reply