What does a proxy do to the IP address a service sees?¶
title: "What does a proxy do to the IP address a service sees?" card_id: "IP-066" status: "complete" source_document: "https://docs.google.com/document/d/1EKXGA_V0MfyX21gKwvQjKUdJUZQ-VSRp3kexACed-0w/edit?usp=drivesdk"
What does a proxy do to the IP address a service sees?¶
What does a proxy do to the IP address a service sees?¶
A proxy sits between a device and the service it wants to contact.
Instead of connecting directly to the destination, the device sends its request to the proxy.
The proxy then makes a connection onwards.
From the destination service’s point of view, the connection normally appears to come from the proxy’s IP address.
The original device may be somewhere else entirely.
This means that resolving the visible address may identify the proxy operator, a rented server, an open proxy or a compromised device acting as a proxy.
It doesn't necessarily identify the person who originated the request.
A proxy can be configured in a browser, application or operating system. Some are commercial privacy services. Others are operated by workplaces to manage web traffic.
An offender could also run a private proxy on rented or compromised infrastructure.
The proxy’s access to information depends on how it operates and what type of traffic passes through it.
For ordinary unencrypted traffic, it may be able to see the request and content.
For an encrypted HTTPS connection, the proxy may know the destination the client asked it to connect to without necessarily seeing the encrypted content exchanged afterwards.
Some managed workplace proxies deliberately inspect encrypted traffic using certificates installed on organisational devices.
The records available will therefore vary.
A proxy service might hold an account, payment details, connection timestamps or logs linking an incoming address with an outgoing connection.
An open or compromised proxy may hold no useful records at all.
A proxy isn't automatically the same as a VPN.
A VPN commonly tunnels a broader range of device traffic through a VPN service. A proxy may relay traffic only for a particular application or protocol.
Both can cause an online service to record an intermediary address rather than the user’s ordinary connection.
The visible proxy IP identifies the system that contacted the destination.
It doesn't, without records connecting the two sides of the proxy, reveal where the request originally came from or who was responsible for it.