Question 2.1 (50 points):
The forms of non-repudiation (non-repudiation of sender, non-repudiation of receipt and non-repudiation of actions) discussed in this week module are important to achieving information security since they offer a method through which the subject cannot deny performing a specific action. This is achieved through the assignment of a unique digital signatures to messages and actions that help in clearly identifying the sender, recipient, as well as, actions carried out.
The forms of non-repudiation improve system security since they can help in tracing the sender and receiver. In the case of non-repudiation of sender, the sender of a message is clearly identified and a digital signature assigned to his or her message or action. This implies that in case the sender denies he or she sent the message or a specific action artifacts created as a result of non-repudiation can be used in correctly identifying the sender. This improves system security since the sender of a specific message can easily be traced.
On the other hand, non-repudiation also creates artifacts that can also be used in identifying the recipient of a message or an action. Similarly, if a recipient denies he or she sent the message or a specific action artifacts created as a result of non-repudiation can be used in correctly identifying the recipient. In the non-repudiation of actions, system logs containing actions performed, as well as, the user performing the actions can also help in correctly identifying the origin of specific actions on a system hence improving system security. This implies that system security is improved using active logs that show all actions carried out and their origin. This can provide excellent information during system audits where security analysts can determine the origin and destination of specific messages or actions.
Question 2.2 (50 points):
There are numerous security Domains and sub-domains that are applicable to personal computer (workstation) security in a business context. The first domain is the physical security. This refers to the physical security of the room that the personal computer is placed within. A secure room ensures that access to the computer is highly controlled and limited to users authorized to access the personal computer.
The second security domain is access control. This takes into account the following subdomains sign in policies, logging out policies and user authorization. Access control is critical since it helps in ensuring that only authorized users access a system. It also controls what the user can access, read, or write within the system based on their user type (administrator, or limited user).
The third security domain applicable to a personal computer is user authentication. This security domain is within the access control security-domain. This has numerous sub-domains including user names, password policies, and biometric authentication. This domain and subdomains are critical in ensuring that only authorized users can access a specific workstation.
The fourth security domain applicable in personal computers is network security. Network security is critical since personal computers are connected to networks or the internet. The specific subdomains are communication security, network penetration testing, network monitoring, and network access control. These are critical in ensuring that the network and its users are protected.
The last security domain is application security. The subdomains in this domain are data security, antivirus software, spyware, and other security applications. This help in protecting the personal data stored on the personal computer from hacking, and corruption by viruses.
