What does pinging an IP address actually prove?¶
title: "What does pinging an IP address actually prove?" status: "complete" source_document: "https://docs.google.com/document/d/1ZFvyvsEB1IdVXC9hxUpLpE-rvDir_VqkdLTdLTuwsKY/edit?usp=drivesdk"
What does pinging an IP address actually prove?¶
A ping sends a network message to an IP address and waits for a reply.
It commonly uses the Internet Control Message Protocol, or ICMP. If a reply is received, it shows that something associated with the address returned an ICMP response at that time.
That response doesn't necessarily come from the device or service you are interested in. It might be generated by a router, firewall, load balancer, hosting platform or another network component. A shared or translated address may also represent several internal systems.
A successful ping doesn't prove that a website, account or application is active. It doesn't show which services are running, who controls the responding system or whether the address was involved in an earlier event.
Silence is equally limited. Networks frequently block or ignore ICMP traffic. A firewall may permit web or application connections while refusing ping requests. The system might also be offline temporarily, congested, rate-limiting replies or configured not to respond.
The result relates to the time the test was performed. Dynamic allocation and cloud reassignment mean that the address may now lead to infrastructure unrelated to the system that used it during the event being investigated.
Take care when conducting active checks. A ping creates traffic towards the target and may be recorded by security systems. Any testing should have a defined investigative purpose and comply with the authority, policy and operational controls that apply.
A ping response establishes that an ICMP reply apparently returned from the tested address or associated infrastructure at that time. No response establishes only that no reply was received. Neither result identifies the device, user or person responsible for the activity under investigation.