Question

You have been asked to design a secure system that requires strong authentication and authorization. The system must be designed so that communications between parts of the system cannot be intercepted and read by an attacker. Suggest the most appropriate client-server architecture for this system and, giving reasons for your answer, propose how functionality should be distributed between the client and the server systems.

Short answer

Use a client-server architecture with TLS for secure communication and implement MFA for authentication and RBAC for authorization.

Step-by-step solution

Identify Architectural Needs

To accommodate strong authentication and ensure secure communication, a client-server architecture capable of supporting these requirements is essential. We need to ensure that data transferred across the network is protected against interception, and that the integrity and authenticity of users are verified.

Choose Secure Communication Protocol

To prevent communication from being intercepted and read, it is vital to use Transport Layer Security (TLS) or Secure Socket Layer (SSL) protocols. These protocols encrypt data in transit, ensuring that any intercepted data cannot be decrypted without the appropriate keys.

Select Authentication Mechanism

For strong authentication, consider using multi-factor authentication (MFA) which may include something the user knows (password), something the user has (security token), and something the user is (biometric verification). This ensures that only legitimate users gain access to the system.

Assign Roles in Architecture

The client should handle user authentication and basic request initiation, ensuring that necessary credentials and authorization tokens are transmitted to the server. Meanwhile, the server should manage the main business logic, authorization processing, and data storage, ensuring all requests are logged and verified.

Implement Authorization Controls

Implement role-based access control (RBAC) on the server to ensure that users have access only to the data and functions necessary for their role. This limits the potential damage if a user's credentials are compromised.

Key concepts

Authentication Mechanisms

When discussing secure systems, authentication mechanisms are vital in verifying the identity of users. An effective authentication process ensures that only legitimate users can gain access to resources. Multi-Factor Authentication (MFA) is a popular choice in today's secure systems. This process requires users to provide multiple evidence of identity. For example, a typical MFA might include:

• Something you know: like a password or PIN.
• Something you have: such as a smartphone app or security token.
• Something you are: biometric data like fingerprints or facial recognition.

Incorporating these elements enhances security by ensuring that even if one form of authentication is compromised, unauthorized access is still difficult. It is crucial to balance security with usability when designing authentication processes to avoid user frustration.

Client-Server Architecture

The client-server architecture forms the backbone of many secure systems. It separates responsibilities between clients (users) and the servers (the system). In this architecture type, clients make requests to access specific resources, while servers fulfill those requests by managing and storing data.

One effective way to design this architecture is to delegate specific responsibilities:

• Client Side: Handles the user interface and authentication requests. Clients must securely transmit credentials and authentication tokens to the server.
• Server Side: Manages business logic, data storage, and processes all received requests, ensuring they are adequately authenticated and authorized. Using protocols like TLS or SSL, the server can protect data in transit from interception.

This distribution allows scalability, maintains robust security protocols, and ensures that sensitive operations are conducted behind secure server environments. This setup not only enhances security but also helps in better management of network traffic.

Authorization Controls

Once users are authenticated, ensuring they only access data and functions they are permitted to is crucial. This is where authorization controls come into play, specifically, Role-Based Access Control (RBAC).

RBAC assigns users to predefined roles, each having specific permissions. For example, an employee role might have access to everyday operational data, while a manager role could access more sensitive and comprehensive information. This system limits access and potential misuse if a user's credentials are compromised, ensuring only necessary permissions are granted:

• Efficiency: Streamlines the assigning of permissions, reducing administrative overhead.
• Security: Minimizes the risk of unauthorized access by enforcing the principle of least privilege.

Implementing RBAC effectively requires thorough planning and understanding of user roles within the organization. By doing so, organizations can maintain security and efficiency in accessing and managing resources. This ensures that every user action can be monitored and accounted for, maintaining a secure operational environment.