Question 1: Correct Which type of communication path-sharing technology do all 802.11 standards for wireless networking support?
Correct Answer: C CSMA/CD
Correct Answer: Polling Correct Answer: c Token passing
Correct Answer: CSMA/CA
Explanation 802.11x standards for wireless networking all support the CSMA/CA (Carrier Sense Multiple Access/Collision Avoidance) type of communication path-sharing technology. This allows multiple baseband clients to share the same communication medium CSMA/CA works as follows:
1. The system asks for permission to transmit. 2. A designated authority (such as a hub, router, or access point), grants access when the communication medium is free. 3. The system transmits data and waits for an ACK (acknowledgment) 4. If no ACK is received, the data is retransmitted. Polling is a mechanism where one system is labeled as the primary
inquire whether they have data to transmit. Token passing is a mechanism that uses a digital pass card. Only the system holding the token is allowed to communicate CSMA/CD (Carrier Sense Multiple Access/Collision Detection) is the technology used by Ethernet. CSMA/CD works as follows:
1. The system listens for traffic. If the line is clear, the system begins transmitting. 2. During the transmission, the system listens for collisions. 3. If no collisions are detected, the communication succeeds. If collisions are detected, an interrupt jam signal is broadcast to stop all transmissions. Each system waits a random amount of time before starting over at step 1.
References 9.1.3 Wireless Architecture Facts q_wireless_arch_csmaca_np6.question.fex Question 2: Incorrect Match the wireless signaling method on the left with its definition on the right. Transfers data over a radio signal by switching channels at random within a larger frequency band. DSSS FHSS Makes the transmitted bandwidth signal wider than the data stream needs. FHSS DSSS Encodes data over a wireless network using non-overlapping channels.
OFDM Explanation Freguency-hopping spread spectrum (FHSS) transfers data over a radio signal by switching channels at random within a larger frequency band. Direct-sequence spread spectrum (DssS) makes the transmitted bandwidth signal wider than the data stream needs
Orthogonal Frequency Division Multiplexing (OFDM) encodes data
over a wireless network using non-overlapping channels.
References 9.1.3 Wireless Architecture Facts q_wireless_arch_facts_np6.question.fex Question 3: Incorrect Which of the following is true of a wireless network SSID?
Correct Answer: Groups wireless devices together into the same logical network.
Incorrect response: o Is a 48-bit value that identifies an AP.
Correct Answer: 0 Enables wireless interconnection of multiple APs
Correct Answer: Coordinates all communications between wireless devices
Explanation The SsiD, also called the network name, groups wireless devices together into the same logical network
: All devices on the same network (within the Bss and Ess) must have the same SSID. . The SSID is a 32-bit value that's inserted into each frame. The SSID is case sensitive. The SsID is sometimes called the EsSID (extended service set ID) or the BSSID (basic service set ID). In practice, each term means the same thing. However, ssiDs, EssiDs, and BSSIDs are technically different. An access point (AP) is a device that coo