80211 Tutorial (3) [Read-Only] [Compatibility Mode]

802.11 WLAN Systems – a tutorial The Leader in Wireless LAN TestingAgendaIntroductionWLAN network basicsPhysical layer (radio) technologiesPtProtocol archithitecture802.11 MAC protocolSecurity protocols inin WLANsWLANsAdvanced topics in Wireless LAN standardsWLAN testing challenges and test metricsConclusionWhat is a WLAN? What is 802.11?Wireless LANs (WLANs) are LANs that use RF instead of cable or optical fiberfiber • Allows high-speed data transfer without wires or cables• Supports typical enterprise applications (e-mail, file transfer, audio/video conferencing, etc)• First introduced in 1999, evolved from legacy RF data technologies such as Hiperlan• 120 million ports of WLAN shipped worldwide last year (virtually all laptops have WLAN interfacesinterfaces now)now)IEEE 802.11-1999 is the basic standard governing wireless LANs• Standardized by the IEEE 802.11 group, which is a working group in the IEEE 802 LAN/MAN SSttandards CCommittee ((LMSC)LMSC)• Formed in 1991 to standardize a 1 Mb/s RF-based data network technology• Completed its work in 1999 with the first 802.11 wireless LAN standard•• Now ddrivingriving almost all WWLANLAN ttechnologyechnology development worldwidePros and Cons of 802.11Pros.. Cons..Mobility Shared-medium technology –bandwidth limited by RF Compatible with IP networksspectrumHiggph speed data connectivityLimited number of non-Unlicensed frequenciesoverlapping channelsHighly secureMultipath effects ...