312-38 Online Practice Questions and Answers

Correct Answer: signature

A digital signature is a technique to authenticate digital documents by using computer cryptography. A digital signature not only validates the sender's identity, but also ensures that the document's contents have not been altered. It verifies that the source and integrity of the document is not compromised since the document is signed. A digital signature provides the following assurances: Authenticity, Integrity, and Non-repudiation. Microsoft Office 2007 Excel and Word provide a feature known as Signature line to insert a user's digital signature on a document.

Correct Answer: Honeynet

Honeynet is a prime example of a high-interaction honeypot. Two or more honeypots on a network form a honeynet. Typically, a honeynet is used for monitoring a larger and/or more diverse network in which one honeypot may not be sufficient. Honeynets and honeypots are usually implemented as parts of larger network intrusion-detection systems. A honeyfarm is a centralized collection of honeypots and analysis tools.

Correct Answer: E

Correct Answer: B

Correct Answer: D

Correct Answer: D

Correct Answer: A

Correct Answer: DB

Cost-benefit analysis is a process by which business decisions are analyzed. It is used to estimate and total up the equivalent money value of the benefits and costs to the community of projects for establishing whether they are worthwhile. It is a term that refers both to: helping to appraise, or assess, the case for a project, program, or policy proposal; an approach to making economic decisions of any kind. Under both definitions, the process involves, whether explicitly or implicitly, weighing the total expected costs against the total expected benefits of one or more actions in order to choose the best or most profitable option. The formal process is often referred to as either CBA (Cost-Benefit Analysis) or BCA (Benefit-Cost Analysis). Answer option A is incorrect. Business Continuity Planning (BCP) is the creation and validation of a practiced logistical plan that defines how an organization will recover and restore partially or completely interrupted critical (urgent) functions within a predetermined time after a disaster or extended disruption. The logistical plan is called a Business Continuity Plan. Answer option C is incorrect. Disaster recovery is the process, policies, and procedures related to preparing for recovery or continuation of technology infrastructure critical to an organization after a natural or human-induced disaster. Disaster recovery planning is a subset of a larger process known as business continuity planning and should include planning for resumption of applications, data, hardware, communications (such as networking) and other IT infrastructure. A business continuity plan (BCP) includes planning for non-IT related aspects such as key personnel, facilities, crisis communication and reputation protection, and should refer to the disaster recovery plan (DRP) for IT related infrastructure recovery / continuity.

Correct Answer: D

Internet Protocol Security (IPSec) is a standard-based protocol that provides the highest level of VPN security. IPSec can encrypt virtually everything above the networking layer. It is used for VPN connections that use the L2TP protocol. It

secures both data and password. IPSec cannot be used with Point-to-Point Tunneling Protocol (PPTP).

Answer option B is incorrect. The Internet Protocol (IP) is a protocol used for communicating data across a packet-switched inter-network using the Internet Protocol Suite, also referred to as TCP/IP.IP is the primary protocol in the Internet

Layer of the Internet Protocol Suite and has the task of delivering distinguished protocol datagrams (packets) from the source host to the destination host solely based on their addresses. For this purpose, the Internet Protocol defines

addressing methods and structures for datagram encapsulation. The first major version of addressing structure, now referred to as Internet Protocol Version 4 (IPv4), is still the dominant protocol of the Internet, although the successor,

Internet Protocol Version 6 (IPv6), is being deployed actively worldwide.

Answer option C is incorrect. Point-to-Point Protocol (PPP) is a remote access protocol commonly used to connect to the Internet. It supports compression and encryption and can be used to connect to a variety of networks. It can connect to a network running on the IPX, TCP/IP, or NetBEUI protocol. It supports multi-protocol and dynamic IP assignments. It is the default protocol for the Microsoft Dial-Up adapter. Answer option A is incorrect. Layer 2 Tunneling Protocol (L2TP) is a more secure version of Point-to-Point Tunneling Protocol (PPTP). It provides tunneling, address assignment, and authentication. It allows the transfer of Point-to-Point Protocol (PPP) traffic between different networks. L2TP combines with IPSec to provide tunneling and security for Internet Protocol (IP), Internetwork Packet Exchange (IPX), and other protocol packets across IP networks.

Correct Answer: D

Selective Acknowledgment (SACK) is one of the forms of acknowledgment. With selective acknowledgments, the sender can be informed by a data receiver about all segments that have arrived successfully, so the sender retransmits only those segments that have actually been lost. The selective acknowledgment extension uses two TCP options: The first is an enabling option, "SACK-permitted", which may be sent in a SYN segment to indicate that the SACK option can be used once the connection is established. The other is the SACK option itself, which can be sent over an established connection once permission has been given by "SACK-permitted". Answer option A is incorrect. Block Acknowledgment (BA) was initially defined in IEEE 802.11e as an optional scheme to improve the MAC efficiency. IEEE 802.11n capable devices are also referred to as High Throughput (HT) devices. Instead of transmitting an individual ACK for every MPDU, multiple MPDUs can be acknowledged together using a single BA frame. Block Ack (BA) contains bitmap size of 64*16 bits. Each bit of this bitmap represents the status (success/ failure) of an MPDU. Answer option B is incorrect. With Negative Acknowledgment, the receiver explicitly notifies the sender which packets, messages, or segments were received incorrectly that may need to be retransmitted. Answer option C is incorrect. With Cumulative Acknowledgment, the receiver acknowledges that it has correctly received a packet, message, or segment in a stream which implicitly informs the sender that the previous packets were received correctly. TCP uses cumulative acknowledgment with its TCP sliding window.