MIS 111 Lecture Notes - Lecture 20: Multipath Propagation, Wireless Lan, Norman Abramson

• School: University of Arizona
• Department: Management Info Systems Main
• Course: MIS 111
• Professor: W.Neumann, M.Patton

Document Summary

Wireless link characteristics: differences from wired link , decreasing signal strength: radio signal attenuates as it propagates through matter (path loss) Wireless transmission media: wireless transmission over unguided media refers to the methods of carrying data through the air using infrared, radio, or microwave signals. Wireless transmission: human voice meets the criteria for wireless transmission, unguided media (air) Wednesday, october 5, 2016: decreasing signal strength (distance, interference (noise, multi-path (echoes) Wireless technologies: wireless lans: 802. 11, wifi, cellular telephone networks, long-range: microwaves, satellite, short-range: bluetooth, rfid. 802. 11 has 11 channels: channels 1, 6, and 11 are non-overlapping. Each ap coverage area is called a cell : wireless nodes can roam between cells. About 75 m range outdoors: 802. 11a, 802. 11b (most prevalent, 802. 11g https://encrypted-tbn3. google. com/images?q=tbn:and9gcredbncrvluagjkooqxchl7vlnrwvkwqpp5vtaxo0ni79i85mfzyq. Ua guest ua wifi: anyone within range can connect, no encryption, restricts use of some personal email clients. Tkip: less bandwidth available on campus, only those with ua netids can connect, encryption, wpa/wpa2.