CompTia A+ : Chapter 7 Flashcards
Which of the following wireless IEEE standards operate on the 2.4Ghz radio frequency and are directly compatible with each other? (Choose two)
Both 802.11b and 802.11g operate in the 2.4Ghz frequency and have similar transmission standards. [Some legacy devices are listed as 802.11b/g, meaning they will all work with either system. Alternatively, 802.11a and 802.11ac operate in the 5Ghz range.]
What is the primary function of the SSID?
A service -set identifier or SSID is the unique name given to the wireless network. All hardware that is to participate on the network must be configured to use the same SSID. Essentially, it is the network name. When you are using Windows to connect to a wireless network, all available wireless networks are listed by their SSID.
Which of the following are features that allow 802.11ac to achieve higher data throughput? (Choose Two)
Channel bonding and MIMO. [ Channel bonding is the combination of multiple smaller channels into one larger channel for greater bandwidth. MIMO is enhanced over 802.11n to allow for multiple inputs and outputs. 802.11ac also uses beamforming, but that helps the range, not the throughput.]
Which of the following is the most secure wireless encryption standard for 802.11 networks?
WPA3 is the safest but among the options WPA 2 is the safest [ WEP was the original encryption standard developed for Wifi networks and is easily hacked. SAFER+ is used to encrypt Bluetooth communication.]
You are upgrading a wireless network from Wifi-5 over to Wifi-6. Which of the following statements is NOT correct?
Wifi 6 is faster than Wifi 5 and the network range is similar. More users should be able to access each access point, not fewer. Devices may have lower power usage with Wifi 6 due to a new sleep feature
You have just installed a wireless router on your home network. Which of the following should you do to make it highly secure? (Choose all that apply.)
You should always change the default admin name and password, as well as the default SSID when installing a new wireless router. Enabling encryption is also a good idea, but WPA, WPA2, and WPA3 are all better options than WEP.The channel has nothing to do with security.
You are setting up a small office network for a client. Which internet service would you recommend to provide the best speed?
Of the options listed, fiber provides the best speed. [ DSL and cable provide similar speeds but can’t match fiber. Satellite is the slowest of the options listed.]
Which service allows users with private IP addresses to access the Internet using a public IP address?
NAT or Network Address Translation allows users with private IP addresses to access the internet with public IP addresses [ NAT is installed on a router and translates the private IP address into a public address for the user to access the internet. DHCP assigns IP configuration information to clients. DNS resolves hostnames to IP addresses. DSL is a type of broadband internet access.]
You are installing a single 802.11g wireless network. The office space is large enough that you need three WAPs. What channels should you configure the WAPs on to avoid communication issues?
There are 14 communications channels in the 2.4 Ghz range, but only the first 11 are configurable. The three nonoverlapping channels are 1, 6, and 11.
You are setting up a wireless network. Which wireless standards would give the users over 40 Mbps throughput? (Choose all that apply)
Of the listed options: 802.11ac (1300Mbps), 802.11g(54Mbps), and 802.11n (600 Mbps) – give users the required throughput. 802.11ax would as well, but was not listed.
You have been asked to configure a network for a small office. The wireless router is installed, and now you need to connect the client computers. What do you enter on the client computers to connect to the router?
To join the network, the client computers need to find the SSID, ensure that the security settings are correct (to match the router), and enter the security passphrase. As an administrator, you should have configured this passphrase to be different from the router’s administrator password.
Which of the following technologies can operate in the 125Khz to 134Khz range?
RFID or Radio frequency identification can operate in three frequency bands: 125-134, 13.56Mhz, or 856Mhz to 960Mhz. Bluetooth is 2.4Ghz. NFC is 13.56Mhz, and LTE is between 600Mhz and 6Ghz.
Due to channel interference, you are upgrading a wireless network from Wifi-5 to Wifi-6. Which feature of Wifi-6 reduces channel interference?
BSS or Basic Server Set coloring, which adds a field to the wireless frame that distinguishes it from others. [OFDMA or Orthogonal Frequency Division Multiple Access is a modulation technique that improves speed because it allows transmission to multiple clients at once. MU-MIMO also increases speed because in Wifi 6 it works for uplink connections as well as downlink ones. DFS or Dynamic Frequency selection was introduced with 802.11n, and it detects radar interference and adjusts frequencies accordingly.]
Which of the following security standards was the first to introduce a dynamic 128-bit per packet security key?
TKIP [ WEP could use a 64-bit or 128-bit security key, but it was a static key. AES and CCMP came after TKIP.]
You are running an 802.11g wireless router in mixed mode. You have three 802.11g wireless NICs using the router. A new user connects using an 802.11b wireless NIC. What will happen?
The good news is 802.11g is backwards compatible with 802.11b. The bad news is, if you run in a mixed environment, all devices that communicate with the WAP(or router) will be forced to slow down or accommodate the older technology.