In cybersecurity, telemetry is the lifeblood of all threat detection. It’s the continuous, raw data stream of everything happening across your digital systems—your endpoints, networks, and cloud applications.
This isn't just one type of data. Telemetry is a massive, high-volume flow of information that includes:
Process execution logs (what programs are running)
Network connection data (who is talking to whom)
User login and authentication events
API calls and cloud configuration changes
Firewall and DNS request logs
File creation and modification events
In short: it's the raw evidence of every action and event.
So, It's Just a Lot of Data?
On its own, telemetry is just... noise. A single laptop can generate millions of data points every hour, and the vast majority of this is totally normal, benign activity.
But buried deep in that mountain of noise is the single, subtle clue that an attacker is present.
The entire goal of modern threat detection isn't just to collect telemetry; it's to sift through those billions of events to find the one that matters. Without this data stream, you're operating in the dark. You have no logs, no evidence, and no way to spot a breach. Effective security is impossible without it.
What Uses Telemetry?
Telemetry is the raw ingredient; security tools are the chefs. Almost every major security platform is fundamentally a telemetry-processing engine.
SIEM (Security Information and Event Management): These platforms are designed to be giant data lakes. They collect telemetry from all sources (firewalls, servers, apps) to correlate events and store them for compliance.
EDR (Endpoint Detection and Response): An EDR agent's primary job is to collect deep endpoint telemetry—like what EDR looks for—and analyze it for signs of an active attack.
XDR (Extended Detection and Response): This is the new buzzword. It simply means "extended" telemetry. XDR platforms combine data from multiple sources (like endpoints, cloud, identity, and email) to get a bigger, more connected picture of a potential threat.
The Big Challenge: Signal vs. Noise
The problem isn't getting telemetry. Modern systems produce too much of it. As a result, many security teams are drowning in data they can't possibly analyze, a problem industry experts often call the "data deluge".
Attackers know this. They try to blend in, making their malicious activity look like normal IT operations. A real breach isn't a flashing red light; it's a single, quiet log line that looks almost normal.
This is why the "signal vs. noise" problem is the single biggest challenge in cybersecurity. It's the job of automated platforms (like SIEMs) and, ideally, trained human threat hunters to sift the data, find the true anomaly, and provide the context to know if it's a real threat or just "weird-but-normal" IT stuff.
Ultimately, telemetry is your evidence. It's the raw material for finding, investigating, and responding to cyberattacks. Without it, you’re just guessing.
FAQs
Volume: The sheer amount of data is massive, making it expensive to store and slow to search.
Speed: It's generated 24/7 in real-time, and you have to analyze it just as fast.
Noise: 99.999% of telemetry is normal, benign activity. Finding the tiny signal of an attack in that massive haystack is incredibly difficult.