WifiBasics

Reference https://www.youtube.com/watch?v=0fpyfPUyfic Multipath:  A signal from the transmitter may travel through different paths due to reflections from obstacles along the path. These signals arrive at different times and different angles  at the receiver and  interfere with signal from direct line of sight. This causes distortion of signal at the receiver. Prior to 802.11n this multi-path had a adverse effect. But from 802.11n , the multi path effect has been used constructively,  1.  Using spatial multiplexing, different data streams are transmitted from different antennas  2.  Transmit diversity, where the same data is sent through different transmitter radio chain and processed at the receiver 3. Multiple  identical data streams  received at the the receiver by different radio chains can be processed using MRC algorithms Multi path is a requirement for sending multiple streams. If multipath effect is not there , multiple spatial stream...

  1) Basic security enhancements in WPA3 vs. WPA2 WPA2 flaws - susceptible to brute force and offline dictionary attacks where passwords can be recovered offline dictionary attack : 4 way hand shake can be captured and passwords can be recovered. The attacker can capture the 4 way handshake. Make a guess of password from a dictionary list Run  the password through know function/algorithm(PBKDF2) that is defined in the standard to get the PMK/PSK .  From the captured message compute the PTK using          Anonce, Snonce, Cl Mac addr and AP Mac Address are known from the 4 way              handshake          Computed PMK from guessed passphrase          Compute MIC If the MIC matches with that in the captured message, PTK keys is correct ad password is cracked. In WPA3, even if password can be guessed, the PMK cannot ...