QUESTION 16 Logical link control layer handles packet retransmission and converting packets to upper layer. True O False QUESTION 17 Which of following regarding MAC/IP addresses is FALSE? O A NIC's MAC address can not be changed while IP address can IPv4 address is longer than MAC address. MAC address is assigned by vendor while IP address is not MAC address is used by layer 2 device to forward packets while IP address is used by layer 3 device QUESTION 18 ( Which of following regarding the sequence number in 802.11 frame is FALSE? It can be used to identify packet fragments It can be used to identify duplicated packets It has 2 bytes (16 bits) in the frame header. It can be used to assist medium access control QUESTION 32 In WLAN, a distribution system connects O APs in the same BSS APs in the same ESS Stations connected to the same AP Stations are not connected to the same AP but can hear each other QUESTION 33 CSMA/CA can avoid al collisions because all stations cooperatively check whether the medium is busy before transmission True False QUESTION 34 In which of following there is no contention in 802.11 network? DCF mode O PCF mode O Infrastructure mode O Ad hoc mode QUESTION 35 In CSMA/CA a station that is waiting to transmit will sense the medium on the channel being used and wait until the medium is free of other transmissions. If the medium was busy and then once the medium becomes free. O It will transmit immediately O It will wait for DIFS and then transmit It will wait for DIFS and a random back-off time before transmit It will wait for the time of duration field of previous frame has expired QUESTION 36 The slot time of contention window of CSMA/CA is different for 802.11 and 802.11 True O False IIIt Tvet QUESTION 30 Which security feature is handled by wireless LAN switch? Access control O Rogue AP detection Identifying unauthorized users All of above