CompTIA Security+ Question A-36

Which of the following network design elements allows for many internal devices to share one public IP address?

A. DNAT
B. PAT
C. DNS
D. DMZ

Answer: B

Explanation:
Port Address Translation (PAT), is an extension to network address translation (NAT) that permits multiple devices on a local area network (LAN) to be mapped to a single public IP address. The goal of PAT is to conserve IP addresses.

Most home networks use PAT. In such a scenario, the Internet Service Provider (ISP) assigns a single IP address to the home network’s router. When Computer X logs on the Internet, the router assigns the client a port number, which is appended to the internal IP address. This, in effect, gives Computer X a unique address. If Computer Z logs on the Internet at the same time, the router assigns it the same local IP address with a different port number. Although both computers are sharing the same public IP address and accessing the Internet at the same time, the router knows exactly which computer to send specific packets to because each computer has a unique internal address.

CompTIA Security+ Simulation 12

Which of the following BEST describes the type of attack that is occurring? (Select TWO).

A. DNS spoofing
B. Man-in-the-middle
C. Backdoor
D. Replay
E. ARP attack
F. Spear phishing
G. Xmas attack






Correct Answer: A, E

We have a legit bank web site and a hacker bank web site. The hacker has a laptop connected to the network. The hacker is redirecting bank web site users to the hacker bank web site instead of the legit bank web site. This can be done using two methods: DNS Spoofing and ARP Attack (ARP Poisoning).

A: DNS spoofing (or DNS cache poisoning) is a computer hacking attack, whereby data is introduced into a Domain Name System (DNS) resolver’s cache, causing the name server to return an incorrect IP address, diverting traffic to the attacker’s computer (or any other computer).

A domain name system server translates a human-readable domain name (such as example.com) into a numerical IP address that is used to route communications between nodes. Normally if the server doesn’t know a requested translation it will ask another server, and the process continues recursively. To increase performance, a server will typically remember (cache) these translations for a certain amount of time, so that, if it receives another request for the same translation, it can reply without having to ask the other server again.

When a DNS server has received a false translation and caches it for performance optimization, it is considered poisoned, and it supplies the false data to clients. If a DNS server is poisoned, it may return an incorrect IP address, diverting traffic to another computer (in this case, the hacker bank web site server).

E: Address Resolution Protocol poisoning (ARP poisoning) is a form of attack in which an attacker changes the Media Access Control (MAC) address and attacks an Ethernet LAN by changing the target computer’s ARP cache with a forged ARP request and reply packets. This modifies the layer -Ethernet MAC address into the hacker’s known MAC address to monitor it. Because the ARP replies are forged, the target computer unintentionally sends the frames to the hacker’s computer first instead of sending it to the original destination. As a result, both the user’s data and privacy are compromised. An effective ARP poisoning attempt is undetectable to the user. ARP poisoning is also known as ARP cache poisoning or ARP poison routing (APR).

CompTIA Security+ Simulation 5

For each of the given items, select the appropriate authentication category from the drop down
choices.

Select the appropriate authentication type for the following items:

Correct Answer:


Something you are includes fingerprints, retina scans, or voice recognition.
Something you have includes smart cards, token devices, or keys.
Something you know includes a passwords, codes, PINs, combinations, or secret phrases.
Somewhere you are includes a physical location s or logical addresses, such as domain name, an
IP address, or a MAC address.
Something you do includes your typing rhythm, a secret handshake, or a private knock.

References:
Stewart, James Michael, CompTIA Security+ Review Guide, Sybex, Indianapolis

CompTIA Network+ Question C-84

A network administrator receives a call asking for assistance with connecting to the network. The user asks for the IP address, subnet class, and VLAN required to access the network. This describes which of the following attacks?

A. Social engineering
B. Spoofing
C. Zero-day attack
D. VLAN hopping

Correct Answer: A

CompTIA Network+ Question C-68

A technician needs to set aside addresses in a DHCP pool so that certain servers always receive the same address. Which of the following should be configured?

A. Leases
B. Helper addresses
C. Scopes
D. Reservations

Correct Answer: D

Explanation:
A reservation is used in DHCP to ensure that a computer always receives the same IP address. To create a reservation, you need to know the hardware MAC address of the network interface card that should receive the IP address.
For example, if Server1 has MAC address of 00:A1:FB:12:45:4C and that computer should always get 192.168.0.7 as its IP address, you can map the MAC address of Server1 with the IP address to configure reservation.

CompTIA Network+ Question C-60

Jane, a network technician is preparing to configure a company’s network. She has installed a firewall to allow for an internal DMZ and external network. No hosts on the internal network should be directly accessible by IP address from the internet, but they should be able to communicate with remote networks after receiving a proper IP address. Which of the following is an addressing scheme that will work in this situation?

A. Teredo tunneling
B. Private
C. APIPA
D. Classless

Correct Answer: B

CompTIA Network+ Question C-57

Upon arrival at work, an administrator is informed that network users cannot access the file server. The administrator logs onto the server and sees the updates were automatically installed and the network connection shows limited and no availability. Which of the following needs to be rolled back?

A. The browser on the server
B. The server’s NIC drivers
C. The server’s IP address
D. The antivirus updates

Correct Answer: B

CompTIA Network+ Question C-54

A PC technician has installed a new network printer that was preconfigured with the correct static IP address, subnet mask, and default gateway. The printer was installed with a new cable and appears to have link activity, but the printer will not respond to any network communication attempts. Which of the following is MOST likely the cause of the problem?

A. Damaged cable
B. Duplex mismatch
C. Incorrect VLAN assignment
D. Speed mismatch

Correct Answer: C

Explanation:
If a port is accidentally assigned to the wrong VLAN in a switch, it’s as if that client was magically transported to another place in the network. This would explain the inability to communication with the printer, as it is on a different VLAN.

CompTIA Network+ Question C-33

While troubleshooting a connectivity issue, a network technician determines the IP address of a number of workstations is 169.254.0.0/16 and the workstations cannot access the Internet. Which of the following should the technician check to resolve the problem?

A. Default gateway address
B. Misconfigured DNS
C. DHCP server
D. NIC failure

Correct Answer: C

Explanation:
If a DHCP server fails, the workstations are assigned an address from the 169.254.0.0 address range by Automatic Private IP Addressing (APIPA). APIPA also configures a suitable subnet mask, but it doesn’t configure the system with a default gateway address. This allows communication on the local network, but not externally.

CompTIA Network+ Question C-29

A network technician needs to separate a web server listening on port 80 from the internal LAN and secure the server from the public Internet. The web server should be accessible to the public Internet over port 80 but not the private LAN. Currently, the network is segmented with a network-based firewall using the following IP addressing scheme on each interface:

Which of the following ones should the technician use to place the web server and which of the following firewall rules should the technician configure?

A. Place the web server in the public zone with an inbound rule from eth0 interface to accept traffic over port 80 designated to the web server
B. Place the web server in the DMZ with an inbound rule from eth0 interface to eth1 to accept traffic over port 80 designated to the web server
C. Place the web server in the private zone with an inbound rule from eth2 interface to eth1 to accept traffic over port 80 designated to the web server
D. Place the web server in the DMZ with an inbound rule from eth1 interface to eth0 to accept traffic over port 80 designated to the web server

Correct Answer: B