ISO/IEC 18028-3:2005 provides an overview of security gateways through a description of different architectures.
It outlines the techniques for security gateways to analyse network traffic. The techniques discussed are as follows:

• packet filtering,
• stateful packet inspection,
• application proxy,
• network address translation,
• content analysing and filtering.

Additionally, ISO/IEC 18028-3:2005 provides guidelines for the selection and configuration of security gateways. It gives guidance to choose the right type of architecture for a security gateway, which best meets the security requirements of an organization.