CompTIA JK0-019 Online Practice Questions and Exam Preparation

CompTIA JK0-019 Online Questions & Answers

• Question 481:

  A technician suspects invalid information in the local DNS cache of a workstation. Which of the following commands can be used to clear this?

  A. nslookup
  B. ifconfig
  C. dig
  D. ipconfig
  D. ipconfig

• Question 482:

  Which of the following allows for groups of ports on the same switch to operate as a part of different segmented networks?

  A. RIP
  B. STP
  C. VLAN
  D. MTU
  C. VLAN

• Question 483:

  At which layer of the OSI model do MAC addresses operate?

  A. Data Link
  B. Network
  C. Application
  D. Physical
  A. Data Link

• Question 484:

  Which of the following would be used on a network to ensure access to resources if a critical host becomes unavailable?

  A. QoS
  B. CARP
  C. VLAN
  D. DHCP server
  B. CARP

• Question 485:

  Joe, a network technician, is asked to install a couple new WAP's inside a back warehouse that was added to a main warehouse facility that already has complete wireless coverage on both the 2.4GHz and 5GHz frequencies. Joe already has a complete wireless heat map of the main warehouse. Which of the following is the first step that Joe should do before choosing which WAP's to use?

  A. Conduct a wireless survey of the back warehouse.
  B. Ask the vendor that provided the WAP's for the main warehouse for recommendations.
  C. Ask the systems administrator which WAP's are preferred.
  D. Only order WAP's that support 5GHz channels.
  A. Conduct a wireless survey of the back warehouse.

• Question 486:

  Which of the following standards can operate at either 20MHz or 40MHz channel spacing?

  A. 802.11a
  B. 802.11b
  C. 802.11g
  D. 802.11n
  D. 802.11n

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  The 2.4 GHz ISM band is fairly congested. With 802.11n, there is the option to double the bandwidth per channel to 40 MHz which results in slightly more than double the data rate. However, when in 2.4 GHz, enabling this option takes up to 82%[10] of the unlicensed band, which in many areas may prove to be infeasible.

  The specification calls for requiring one primary 20 MHz channel as well as a secondary adjacent channel spaced ?0 MHz away. The primary channel is used for communications with clients incapable of 40 MHz mode. When in 40 MHz mode, the center frequency is actually the mean of the primary and secondary channels.

• Question 487:

  Which of the following protocols can be implemented to provide encryption during transmission between email gateways?

  A. TLS
  B. PPTP
  C. SSH
  D. HTTPS
  A. TLS

• Question 488:

  A content filter is MOST likely installed on which of the following servers?

  A. Proxy server
  B. TACACS+ server
  C. DNS server
  D. DHCP server
  A. Proxy server

• Question 489:

  In a newly installed LAN, the network administrator receives many calls about intermittent or slow connectivity to the authentication server. Which of the following could cause this problem? (Select TWO).

  A. VLAN configuration error
  B. Cables too short
  C. Cable crosstalk
  D. Incorrect channel
  E. EMI
  F. Wrong subnet mask
  C. Cable crosstalk
  E. EMI

• Question 490:

  A company has recently allowed its employees to telecommute two days a week. The employees MUST have a minimum of 1Mbps non-shared connection to the Internet. Which of the following MUST the employees have at their home in order to connect to the Internet?

  A. ISDN
  B. Cable modem
  C. DSL
  D. Dial-up networking
  C. DSL

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  Digital subscriber line (DSL, originally digital subscriber loop) is a family of technologies that provide Internet access by transmitting digital data over the wires of a local telephone network.