Guideline of Tiers Model for Web and Database Server

Preamble:

• Designing web applications in tiers is a best practice that reduces the attack surface and limits potential damage in case of a compromise.
• Separating the web server and database server ensures that even if the web server is compromised, the database server and valuable data remain protected.
• Data can be categorized as public or non-public.
• Non-public data is often sensitive, confidential, or proprietary, and its access is restricted to authorized identities only.  In contrast, public data is openly accessible to anyone without restrictions.
• While separating the web server and database server is beneficial for general cases, it needs to be taken into consideration for systems handling non-public accessible data.

Objective:

• The main idea is to enforce tiering for systems that would have serious impact when data leakage found.

Guidelines for consideration:

• Tiers model for web and database services is recommended to be adopted by separating web and database services into two separate servers.
• For systems handling non-public data, the Database Management System (DBMS) and its databases should be placed in a secure environment that is not publicly accessible from the Internet.  (i.e.: the DBMS hosted on dedicated servers that are isolated from the web servers)

Use Cases:

Published on:  21 Jan 2025