When an attacker successfully inserts an intermediary software or program between two communicating hosts, it is known as man-in-the-middle attack.

Mandatory Access Control (MAC) is a model that uses a predefined set of access privileges for an object of the system. Access to an object is restricted on the basis of the sensitivity of the object and granted through authorization. Sensitivity of an object is defined by the label assigned to it. For example, if a user receives a copy of an object that is marked as "secret", he cannot grant permission to other users to see this object unless they have the appropriate permission. Answer B is incorrect. DAC is an access control model. In this model, the data owner has the right to decide who can access the data. Answer A is incorrect. Role-based access control (RBAC) is an access control model. In this model, a user can access resources according to his role in the organization. For example, a backup administrator is responsible for taking backups of important data. Therefore, he is only authorized to access this data for backing it up. However, sometimes users with different roles need to access the same resources. This situation can also be handled using the RBAC model. Answer C is incorrect. There is no such access control model as Policy Access Control.

Following are the benefits of information classification for an organization: It helps identify which protections apply to which information. It helps identify which information is the most sensitive or vital to an organization. It supports the tenets of confidentiality, integrity, and availability as it pertains to data. Answer D is incorrect. The concept of integrity ensures that modifications are not made to data by unauthorized personnel or processes. It also ensures that unauthorized modifications are not made to data by authorized personnel or processes. Answer A is incorrect. Information classification cannot reduce the Total Cost of Ownership (TCO).

Explanation/Reference:
Explanation: In the waterfall model, software development can be managed if the developers are limited to go back only one stage to rework. If this limitation is not imposed mainly on a large project with several team members, then any developer can be working on any phase at any time, and the required rework might be accomplished several times. AnswerB is incorrect. The spiral model is a software development process combining elements of both design and prototyping-in- stages, in an effort to combine advantages of top-down and bottom-up concepts. The basic principles of the spiral model are as follows: The focus is on risk assessment and minimizing project risks by breaking a project into smaller segments and providing more ease-of- change during the development process, as well as providing the opportunity to evaluate risks and weigh consideration of project continuation throughout the life cycle. Each cycle involves a progression through the same sequence of steps, for each portion of the product and for each of its levels of elaboration, from an overall concept-of-operation document down to the coding of each individual program. Each trip around the spiral traverses the following four basic quadrants: Determine objectives, alternatives, and constraints of the iteration. Evaluate alternatives, and identify and resolve risks. Develop and verify deliverables from the iteration. Plan the next iteration.
Begin each cycle with an identification of stakeholders and their win conditions, and end each cycle with review and commitment. AnswerD is incorrect. The Prototyping model is a systems development method (SDM). In this model, a prototype is created, tested, and then reworked as necessary until an adequate prototype is finally achieved from which the complete system or product can now be developed. Answer C is incorrect. Rapid Application Development (RAD) refers to a type of software development methodology that uses minimal planning in favor of rapid prototyping.

Explanation/Reference:
Explanation: A penetration testing is a method of evaluating the security of a computer system or network by simulating an attack from a malicious source. The process involves an active analysis of the system for any potential vulnerabilities that may result from poor or improper system configuration, known or unknown hardware or software flaws, or operational weaknesses in process or technical countermeasures. This analysis is carried out from the position of a potential attacker, and can involve active exploitation of security vulnerabilities. Any security issues that are found will be presented to the system owner together with an assessment of their impact and often with a proposal for mitigation or a technical solution. The intent of a penetration test is to determine feasibility of an attack and the amount of business impact of a successful exploit, if discovered. It is a component of a full security audit. Answer: C is incorrect. A paper test is the least complex test in the disaster recovery and business continuity testing approaches. In this test, the BCP/DRP plan documents are distributed to the appropriate managers and BCP/DRP team members for review, markup, and comment. This approach helps the auditor to ensure that the plan is complete and that all team members are familiar with their responsibilities within the plan. Answer: D is incorrect. A walk-through test is an extension of the paper testing in the business continuity and disaster recovery process. In this testing methodology, appropriate managers and BCP/DRP team members discuss and walk through procedures of the plan. They also discuss the training needs, and clarification of critical plan elements. Answer: A is incorrect. A full operational test includes all team members and participants in the disaster recovery and business continuity process. This full operation test involves the mobilization of personnel. It restores operations in the same manner as an outage or disaster would. The full operational test extends the preparedness test by including actual notification, mobilization of resources, processing of data, and utilization of backup media for restoration.