HumenhukCIPP/US Study Guide
Chapter 3: Introduction to Technological Aspects of Privacy

Key Web Infrastructure: Servers, Proxies, VPNs, ISPs and IP Addresses

Reviewed by Victor Humenhuk. Published . Reviewed .

Web content lives on web servers; a proxy server and Virtual private network (VPN) act as gateways that can mask activity. An Internet service provider (ISP) assigns static IP addresses or dynamic IP addresses, and persistent IPs are why some regulators treat IP addresses as personal information.

How this supports CIPP/US study

Use this lesson to identify the legal source, actor, data and activity before applying a rule to a scenario. Continue with the CIPP/US study guide.

Gateways and masking technologies
TechnologyKey privacy function
Proxy serverMasks internal detail (outside site sees only proxy IP), logs interactions, filters malware, caches content
Virtual private network (VPN)Encrypts user-to-proxy traffic, potentially masking content and destination from the ISP; common for employees, less so for consumers
Transport layer security (TLS)Secures the user-server connection against eavesdropping; successor to SSL
Why IP addresses can be personal data

When a static IP address or persistent dynamic IP address does not change, a website can recognize a returning device. This persistent link is why the EU and some other regulators treat an IP address as personal information - while other regulators do not. The same disagreement applies to web server logs containing IPs.

Key terms - quick answers

What is “Web server”?
A computer connected to the internet that hosts and shares web content accessed by browsers.
What is “Proxy server”?
An intermediary server that provides a gateway to the web, can mask activity behind a firewall, logs interactions, filters malware, and caches content.
What is “Virtual private network (VPN)”?
A tool similar to a proxy that encrypts information from the user to the organization's proxy, potentially masking both content and destination from the ISP.
What is “Internet service provider (ISP)”?
A provider, such as a cable or wireless company, that connects users and devices to the internet and assigns IP addresses.

Sources and study method

This independent lesson uses active recall, spaced retrieval and scenario practice. Read the full study method.