In short: EDR vs XDR vs MDR comes down to scope and people. EDR is software that detects and responds to threats on endpoints. XDR extends detection across endpoints, email, identity, cloud and network in one platform. MDR is a 24/7 service in which analysts use EDR or XDR tools to investigate and respond on your behalf.
The short definitions
- EDR (endpoint detection and response) is an agent on laptops and servers that records what happens on the device, detects suspicious behaviour and lets you respond, for example by isolating the machine or rolling back changes. It goes beyond traditional antivirus (endpoint protection, or EPP), which mainly tries to block known-bad files.
- XDR (extended detection and response) takes the same idea across more than one layer. It correlates signals from endpoints, email, identity, cloud apps, cloud workloads and sometimes the network into a single incident, so an analyst sees one attack rather than twenty unrelated alerts.
- MDR (managed detection and response) is not a product but a service. A security operations centre watches your EDR or XDR telemetry around the clock, investigates, hunts for threats and takes agreed response actions.
Put simply: EDR and XDR are what you see with; MDR is who is looking. Our managed detection and response guide explains how MDR services work and how to choose one.
Side-by-side comparison
| EDR | XDR | MDR | |
|---|---|---|---|
| What it is | Software (agent and console) | Software platform | A 24/7 service delivered by people |
| Main data source | Endpoints and servers | Endpoints plus email, identity, SaaS, cloud and network | Whatever EDR or XDR tools the service runs on |
| Who responds | Your IT or security team | Your IT or security team, with more automation | The provider's analysts, within limits you agree |
| Out-of-hours cover | Only if you staff it | Only if you staff it | Included |
| Typical strength | Deep visibility on devices, ransomware rollback on some products | Cross-domain correlation, faster investigation | Expertise and round-the-clock response |
| Main limitation | Blind to identity and cloud attacks that never touch a device | Still needs skilled people to act on it | Only as good as the telemetry and response authority it has |
| Examples | Microsoft Defender for Endpoint, CrowdStrike Falcon, SentinelOne Singularity | Microsoft Defender XDR, TrendAI Vision One, Cisco XDR | Sophos MDR, CrowdStrike Falcon Complete Next-Gen MDR, WatchGuard MDR, ThreatDown MDR |
Where SIEM, SOAR and MXDR fit
Three more terms come up in the same conversations:
- SIEM (security information and event management) collects and stores logs from almost anything (firewalls, servers, SaaS apps, identity providers) and runs detection rules over them. It is broader than XDR but needs more set-up, tuning and people. Microsoft Sentinel is a cloud SIEM; Todyl includes a cloud SIEM module alongside its endpoint and MXDR modules.
- SOAR (security orchestration, automation and response) runs playbooks automatically when certain alerts fire, such as disabling an account and opening a ticket. Many XDR and SIEM platforms now include it.
- MXDR (managed XDR) is MDR delivered on an XDR platform, so the service covers identity, email and cloud rather than just endpoints. Most modern MDR services are effectively MXDR, whatever they call themselves.
Log retention is often the deciding factor. Regulators, insurers and incident responders may ask what happened weeks or months ago, which is beyond what most EDR tools keep. If you need long retention or compliance reporting, a SIEM (or an MDR service that includes one) is worth the extra cost.
Which does a small business need?
For most organisations with up to a few hundred staff and no dedicated security team, the practical answer is EDR plus MDR:
- Start with a solid EDR, or the EDR you already own. Microsoft 365 Business Premium includes Microsoft Defender for Business, which is a good starting point for many small businesses.
- Make sure identity and Microsoft 365 are monitored as well, because account takeover is a more common way in than malware.
- Add an MDR service so that alerts are acted on at night and at weekends.
- Back it up with tested cloud backup so you can recover if prevention fails.
Buying XDR or a SIEM without the people to run it usually produces a console that nobody looks at. Cyber Essentials does not require EDR or MDR, but its malware protection and patching controls are easier to evidence with them; see Cyber Essentials requirements.
Which does a mid-sized organisation need?
Organisations with several hundred to a few thousand users, multiple cloud platforms or regulated data usually need XDR plus MDR, and sometimes a SIEM as well:
- XDR so that phishing, identity, endpoint and cloud events are joined into one incident
- MDR or MXDR so that a SOC works those incidents 24/7, even if you have an internal security person during office hours
- SIEM when you have significant non-Microsoft infrastructure, compliance logging requirements or a need for long retention
- Specialist layers where the risk justifies them, such as identity threat detection and response, cloud workload protection or a dedicated anti-ransomware layer like Halcyon
If you are unsure where you stand, a cloud security assessment will map your current tools and show where the gaps are.
How we help you decide
We are vendor-aware rather than tied to one vendor. We look at the licences you already own (often more than you think, particularly in Microsoft 365), the people you have, and how quickly you need to respond, then recommend the smallest combination of EDR, XDR, SIEM and MDR that closes the gaps.
Contact us for an independent view on which you need.
How Forever Systems helps with cloud security
We are an independent UK IT and cyber security provider. We supply and support a wide range of security platforms, so we recommend what fits your organisation rather than one vendor's answer to everything.
- Assess first: we review what you already own, especially your Microsoft 365 licences, before suggesting anything new
- Vendor-aware advice across secure access, email, identity, data protection, endpoint, MDR, cloud infrastructure, browser, AI and backup, including Cisco Secure, Check Point Harmony and Sophos
- Deployment and migration from a UK team, from tenant hardening to replacing a VPN or an endpoint product
- Ongoing support: policy tuning, alert handling, renewals and regular reviews
- People and certification too: security awareness training and Cyber Essentials
We work with businesses, schools, charities and public sector organisations.
Want an independent view of your cloud security?
Tell Forever Systems what you need and we will come back to you by email with options, not a hard sell.
Contact usFrequently asked questions
Is XDR better than EDR?
XDR covers more than EDR, because it correlates endpoint data with email, identity, cloud and sometimes network signals. That is only better if someone uses it. For a small organisation, a well-run EDR with an MDR service often delivers more protection than an XDR platform nobody monitors.
Does MDR replace EDR?
No. MDR is a service that runs on top of EDR or XDR tools. The MDR provider either supplies the agent as part of the service or works with the EDR you already own.
Is Microsoft Defender an EDR or an XDR?
Both, depending on the product. Microsoft Defender for Endpoint and Defender for Business are EDR. Microsoft Defender XDR is the platform that joins endpoint, email, identity and cloud app signals into unified incidents in the Defender portal.
What is the difference between XDR and SIEM?
XDR is built around a vendor's own security tools and comes with ready-made correlation and response. A SIEM ingests logs from almost any source and is more flexible, but needs more tuning, storage and expertise. Many organisations use both, and the two are converging.
What is MXDR?
MXDR, or managed extended detection and response, is MDR delivered on an XDR platform. The service monitors identity, email and cloud signals as well as endpoints.