Question 1: What happens when a tiny wireless router's security mode is set to WEP?

• It encrypts data between the wireless client and the access point. (Correct answer)
• It translates an internal address or group of addresses into an outside, public address.
• It identifies the wireless LAN.
• It translates IP addresses into easy-to-remember domain names.

Correct answer: It encrypts data between the wireless client and the access point.

Explanation: <br> Data between the wireless client and the access point is encrypted using WEP. IP addresses are converted into simple-to-remember domain names by DNS. An internal address or set of addresses is converted into an external, public address through NAT. The access point can alert clients to its presence using an SSID.

Question 2: Which solution permits only internal FTP servers on private networks to be accessed by external users?

• NAT with overload
• port forwarding (Correct answer)
• static NAT
• dynamic NAT

Correct answer: port forwarding

Explanation: <br> By using port forwarding, it is possible for other users to access devices connected to a private network over the Internet. Based on the port number, the firewall in the router decides if the traffic needs to be forwarded to an internal device. Port numbers are connected to particular services, including FTP, HTTP, HTTPS, and POP3.

Question 3: What is an SSID broadcasting security flaw that is inherently present?

• It allows any host to join the wireless network.
• It sends traffic unencrypted between the wireless access point and the client.
• It broadcasts the identity of the network. (Correct answer)
• It allows unauthenticated access to the wireless network.

Correct answer: It broadcasts the identity of the network.

Explanation: <br> Because an attacker can simply intercept wireless signals and read plain text messages, wireless routers, and access points by default broadcast SSIDs in plain text to all PCs within the wireless range.

Question 4: The hosts on a network are given IP addresses on a dynamic basis by a DHCP server. The configuration for the address pool is 192.168.10.0/24. On this network, three printers require the use of reserved static IP addresses from the pool. How many IP addresses in the pool are still available for other hosts to be assigned?

• 251 (Correct answer)
• 252
• 253
• 254

Correct answer: 251

A /24 subnet provides 256 total IP addresses, but the network address (192.168.10.0) and broadcast address (192.168.10.255) are reserved, leaving 254 usable addresses for hosts. Since three printers require static IP addresses from this usable pool, these three addresses are no longer available for dynamic assignment. Therefore, 254 minus 3 equals 251 addresses remaining available for other hosts.

Question 5: To communicate over the network, a client device on an Ethernet segment requires an IP address. On the network, a DHCP server with the IP address 192.168.1.1 has been set up and activated. How can a client device get an IP address that works on this network?

• Send a DHCPACK packet to the default gateway address
• Send a DHCPDISCOVER message to physical address FF-FF-FF-FF-FF-FF.
• Send a DHCPREQUEST packet to IP address 255.255.255.255.
• Use a statically configured IP address from the pool of IP addresses that is offered by the DHCP server.

When a client device needs an IP address from a DHCP server, it initiates the process by sending a DHCPDISCOVER message. This message is broadcast at both the MAC layer (using FF-FF-FF-FF-FF-FF) and the IP layer (using 255.255.255.255) to ensure that any DHCP server on the local network segment receives it. This broadcast allows the client to find a DHCP server without knowing its specific IP address beforehand.

Question 6: Which two factors are taken into consideration when choosing a network medium for a network?

• the types of data that need to be prioritized
• the number of intermediate devices that are installed in the network
• the environment where the selected medium is to be installed (Correct answer)
• the distance the selected medium can successfully carry a signal (Correct answer)

Correct answer: the environment where the selected medium is to be installed

The environment where a network medium is to be installed is a crucial factor because it dictates the medium's durability, interference resistance, and safety requirements. For instance, outdoor installations require weather-resistant cabling, while industrial environments might need shielded cables to combat electromagnetic interference. These environmental considerations directly influence the type of cable and its specific jacket rating that can be safely and effectively deployed.

Question 7: In the course of encapsulation, at which layer of the OSI model would a logical address be added?

• network layer (Correct answer)
• transport layer
• physical layer
• data link layer

Correct answer: network layer

The network layer (Layer 3) is responsible for logical addressing, specifically IP addresses. During encapsulation, this layer adds the source and destination IP addresses to the data, forming a packet. These logical addresses are essential for routing data across different networks and identifying the ultimate source and destination hosts.