CWNA-107 Certified Wireless Network Administrator Question and Answers

You administer a small WLAN with nine access points. As a small business, you do not run a RADIUS server and use WPA2-Personal for security. Recently, you changed the passphrase for WPA2-Personal in all APs and clients. Several users are now reporting the inability to connect to the network at times and it is constrained to one area of the building. When using a WLAN scanner, you see that the AP covering that area is online and has a strong signal. No other changes have been made to the environment and all access points are the same model. What is the likely problem?

You are troubleshooting an issue reported by several wireless users. The problem is contained to one cell (several users connected to the same AP). You manage the WLAN and no other network devices. After analysis it appears to be a switch problem. What action should be taken?

The requirements for a WLAN you are installing state that it must support unidirectional delays of less than 150 ms and the signal strength at all receivers can be no lower than -67 dBm. What application is likely used that demands these requirements?

When antenna gain is reported in dBI, the gain of the antenna is compared to what theoretical antenna?

An 802.11 WLAN transmitter that emits a 50 mW signal is connected to a cable with 3 dB of loss. The cable is connected to an antenna with 16 dBi of gain.

What is the EIRP power output?

You are troubleshooting a client problem with a 2.4 GHz WLAN connection. The client is experiencing surprisingly low data rates during the work day. You analyze the workspace outside of business hours and detect a strong signal with a typical noise floor at the client location. During working hours, the user works with a laptop in the area and uses an external USB hard drive for continuous data access. The user also states that the laptop works as expected on her home network. The user working approximately 8 feet away from this client experiences no problems.

Based on this information, what is the likely cause of the problem?

You are reporting on the RF environment in your facility. The manager asks you do describe the noise floor noted on the report. Which of the following is the best explanation?

You are configuring an access point to use channel 128. What important fact should be considered about this channels?

You are troubleshooting a WLAN problem and you suspect hidden node as the cause. What should you look for in a protocol analyzer?

You are troubleshooting a problem with interference from a non-802.11 device. Given that the device is not a WLAN device, you cannot use a protocol analyzer and have chosen to use a spectrum analyzer. You want to view the signal from the interfering device over time to see the activity that is generating.

What common spectrum analyzer view should you use for this analysis?

What statement about the IEEE 802.11-2016 QoS facility is true?

Three access points are used within a facility. One access point is on channel 11 and the other two are on channel 1. The two access points using channel 1 are on either side of the access point using channel 11 and sufficiently apart so that they do not interfere with each other when they transmit frames. Assuming no other APs are in the vicinity, is CCI still a possibility in this network and why?

What 802.11 PHY uses available space in very low frequency ranges that is not in use at the time by broadcast video signals?

You are troubleshooting a client issue on a Windows laptop. The laptop can see and connect to 2.4 GHz APs, but is does not even see 5 GHz APs. While evaluating the issue, you determine that this problem is happening for all of the laptops of this model in the organization. Several other tablets connect on channel 48 and channel 52 in the same work areas. What is the likely problem?

In an 802.11 2.4 GHz system, what 22 MHz channels are considered non-overlapping?

An IEEE 802.11 amendment is in the daft state. What impact does this draft amendment have on the 802.11 standard?

What ID is typically mapped to an AP’s MAC address if a single BSS is implemented?

Which directional antenna types are commonly used by indoor Wi-Fi devices in a MIMO multiple spatial stream implementation?

What is the final step in an effective troubleshooting process?

Your consulting firm has recently been hired to complete a site survey for a company. Your engineers use predictive design software for the task, but the company insists on a pre-deployment site visit.

What task should be performed as part of the pre-deployment visit to prepare for a predictive design?