Firewall Approach to Internet Security - Tutorial
Table of Contents
Firewall Approach Overview
How packets are filtered out?
What information is used for filtering decision?
Protecting from the IP spoofing of internal addresses
Allowing only electronic mail traffic
Why Filtering Routers are not enough?
Application Gateways - Proxies
How proxy program works?
How external client is enforced to contact proxy server?
How internal client is enforced to contact proxy server?
Screening Router Architecture
Dual-Homed Host Architecture
Screened Host Architecture
Screened Subnet Architecture