Discretionary Access Control

A.

An identity-based access control is an example of discretionary access control that is based on an individual's identity.Identity-based access control (IBAC) is access control based on the identity of the user (typically relayed as a characteristic of the process acting on behalf of that user) where access authorizations to specific objects are assigned based on user identity.

Rule Based Access Control (RuBAC) and Role Based Access Control (RBAC) are examples of non-discretionary access controls.

Rule-based access control is a type of non-discretionary access control because this access is determined by rules and the subject does not decide what those rules will be, the rules are uniformly applied to ALL of the users or subjects.

In general, all access control policies other than DAC are grouped in the category of non-discretionary access control (NDAC).As the name implies, policies in this category have rules that are not established at the discretion of the user.

Non-discretionary policies establish controls that cannot be changed by users, but only through administrative action.

Both Role Based Access Control (RBAC) and Rule Based Access Control (RuBAC) fall within Non Discretionary Access Control (NDAC).If it is not DAC or MAC then it is most likely NDAC.

BELOW YOU HAVE A DESCRIPTION OF THE DIFFERENT CATEGORIES: MAC = Mandatory Access Control - Under a mandatory access control environment, the system or security administrator will define what permissions subjects have on objects.The administrator does not dictate users access but simply configure the proper level of access as dictated by the Data Owner.

The MAC system will look at the Security Clearance of the subject and compare it with the object sensitivity level or classification level.This is what is called the dominance relationship.

The subject must DOMINATE the object sensitivity level.Which means that the subject must have a security clearance equal or higher than the object he is attempting to access.

MAC also introduce the concept of labels.Every objects will have a label attached to them indicating the classification of the object as well as categories that are used to impose the need to know (NTK) principle.Even thou a user has a security clearance of Secret it does not mean he would be able to access any Secret documents within the system.He would be allowed to access only Secret document for which he has a Need To Know, formal approval, and object where the user belong to one of the categories attached to the object.

If there is no clearance and no labels then IT IS NOT Mandatory Access Control.

Many of the other models can mimic MAC but none of them have labels and a dominance relationship so they are NOT in the MAC category.

DAC = Discretionary Access Control DAC is also known as:Identity Based access control system.

The owner of an object is define as the person who created the object.As such the owner has the discretion to grant access to other users on the network.

Access will be granted based solely on the identity of those users.

Such system is good for low level of security.One of the major problem is the fact that a user who has access to someone's else file can further share the file with other users without the knowledge or permission of the owner of the file.Very quickly this could become the wild wild west as there is no control on the dissimination of the information.

RBAC = Role Based Access Control RBAC is a form of Non-Discretionary access control.

Role Based access control usually maps directly with the different types of jobs performed by employees within a company.

For example there might be 5 security administrator within your company.Instead of creating each of their profile one by one, you would simply create a role and assign the administrators to the role.Once an administrator has been assigned to a role, he will IMPLICITLY inherit the permissions of that role.

RBAC is great tool for environment where there is a a large rotation of employees on a daily basis such as a very large help desk for example.

RBAC or RuBAC =Rule Based Access Control RuBAC is a form of Non-Discretionary access control.

A good example of a Rule Based access control device would be a Firewall.A single set of rules is imposed to all users attempting to connect through the firewall.

Source: KRUTZ, Ronald L.

& VINES, Russel.

D., The CISSP Prep Guide: Mastering the Ten Domains of Computer Security, 2001, John Wiley & Sons, Page 33

and NISTIR-7316 at http://csrc.nist.gov/publications/nistir/7316/NISTIR-7316.pdf and http://itlaw.wikia.com/wiki/Identity-based_access_control.

Discretionary access control (DAC) is a type of access control that allows the owner or administrator of a resource to determine who can access it and how it can be used. It's the most common type of access control used in computer systems and is often used to control access to files, folders, and other resources on a network.

Among the options provided, the correct answer is D, Rule-based access control.

A rule-based access control system uses a set of rules or policies to determine who has access to a particular resource. These rules can be based on a variety of factors, such as user identity, group membership, time of day, and network location. In this type of access control, the resource owner creates and manages the rules for access control. The owner can modify or revoke the access control rules as needed.

Identity-based access control (A) and Task-based access control (B) are not examples of discretionary access control because they are more restrictive than discretionary access control. Identity-based access control relies on a user's identity, such as a username or password, to determine access, while task-based access control uses predefined roles or tasks to determine access.

Role-based access control (C) is also not an example of discretionary access control because it is more restrictive. In role-based access control, access to a resource is determined by the user's role in the organization, rather than by the discretion of the resource owner.

In summary, Discretionary access control (DAC) allows the owner or administrator of a resource to determine who can access it and how it can be used. Rule-based access control is an example of DAC, and it uses a set of rules or policies to determine who has access to a particular resource.