Web Filtering - 4.5
Summary
Web filtering involves controlling access to internet content based on policies set by organizations. Methods include agent-based filtering, where software on client devices decides what content to allow or block, and centralized proxy servers that manage web traffic for an entire network. Additional techniques like URL scanning, DNS filtering, and reputation-based filtering help prevent access to malicious or inappropriate sites by categorizing and analyzing web traffic.
Notes:
Agent-based Filtering
- Software installed on the client device that makes decisions on allowing or disallowing content based on policies.
Centralized (Forward) Proxy
- A server within the internal network that makes and receives requests on behalf of the client to access external internet resources.
- The proxy server analyzes traffic and forwards or blocks it based on predefined rules and policies.
URL (Uniform Resource Locator) Scanning
- Allowing or denying traffic based on the URL (web address).
- Prevents access to suspicious or malicious websites.
Block Rules & Content Categorization
- Generalized categories used for filtering, such as adult content, entertainment, education, and more.
Reputation-based Filtering
- Allowing or blocking access to external sites based on their reputation, for example, allowing safe and trusted sites while blocking risky or potentially malicious ones.
DNS Filtering
- Filtering based on the examination of IP addresses during DNS lookups to prevent connections to harmful websites.