Which of the following is a technique for gathering information about a remote network protected by a firewall?
Correct Answer: A
Fire walking is a technique for gathering information about a remote network protected by a firewall. This technique can be used effectively to perform information gathering attacks. In this technique, an attacker sends a crafted packet with a TTL value that is set to expire one hop past the firewall. If the firewall allows this crafted packet through, it forwards the packet to the next hop. On the next hop, the packet expires and elicits an ICMP "TTL expired in transit" message to the attacker. If the firewall does not allow the traffic, there should be no response, or an ICMP "administratively prohibited" message should be returned to the attacker. A malicious attacker can use firewalking to determine the types of ports/protocols that can bypass the firewall. To use firewalking, the attacker needs the IP address of the last known gateway before the firewall and the IP address of a host located behind the firewall. The main drawback of this technique is that if an administrator blocks ICMP packets from leaving the network, it is ineffective. Answer option B is incorrect. Warchalking is the drawing of symbols in public places to advertise an open Wi-Fi wireless network. Having found a Wi-Fi node, the warchalker draws a special symbol on a nearby object, such as a wall, the pavement, or a lamp post. The name warchalking is derived from the cracker terms war dialing and war driving. Answer option C is incorrect. War driving, also called access point mapping, is the act of locating and possibly exploiting connections to wireless local area networks while driving around a city or elsewhere. To do war driving, one needs a vehicle, a computer (which can be a laptop), a wireless Ethernet card set to work in promiscuous mode, and some kind of an antenna which can be mounted on top of or positioned inside the car. Because a wireless LAN may have a range that extends beyond an office building, an outside user may be able to intrude into the network, obtain a free Internet connection, and possibly gain access to company records and other resources. Answer option D is incorrect. War dialing or wardialing is a technique of using a modem to automatically scan a list of telephone numbers, usually dialing every number in a local area code to search for computers, Bulletin board systems, and fax machines. Hackers use the resulting lists for various purposes, hobbyists for exploration, and crackers - hackers that specialize in computer security - for password guessing.
Question 232
Which of the following protocols is used for E-mail?
Correct Answer: A
Question 233
Stephanie is currently setting up email security so all company data is secured when passed through email. Stephanie first sets up encryption to make sure that a specific user's email is protected. Next, she needs to ensure that the incoming and the outgoing mail has not been modified or altered using digital signatures. What is Stephanie working on?
Correct Answer: B
Stephanie is working on ensuring Data Integrity, which is a critical aspect of information security. It involves maintaining and assuring the accuracy and consistency of data over its entire lifecycle. By setting up digital signatures, Stephanie ensures that the data, in this case, the email content, has not been altered or tampered with during transit. This process provides a means to verify the origin of the message and confirms that the message received is the same as the message sent, thereby safeguarding the integrity of the data.
Question 234
Identify the network topology where each computer acts as a repeater and the data passes from one computer to the other in a single direction until it reaches the destination.
Correct Answer: A
Question 235
Which of the following is an example of MAC model?
Correct Answer: D
The Bell-LaPadula model is an example of a Mandatory Access Control (MAC) model. It is designed to maintain the confidentiality of information by enforcing access controls based on security classification levels. This model ensures that subjects (users) with a certain clearance level cannot read data at a higher classification level (no read-up) and cannot write data to a lower classification level (no write-down), thus preventing unauthorized access and information flow not permitted by the policy.