Microsoft Sentinel vs. Microsoft Defender - What’s the Difference?

For businesses, the cyber security stakes are high: data breaches, regulatory compliance, and the all-important preservation of customer trust. But the security landscape is more complex than ever, and picking the right tools can feel like trying to fit puzzle pieces into a very dynamic, and occasionally hostile, picture.

Microsoft Sentinel and Microsoft Defender both help businesses stay secure, but serve distinct roles. Microsoft products can be confusing (the constant name changes don’t help), so we’ll help you understand where each shines.

Microsoft Sentinel – Cloud-Based SIEM

Sentinel is a cloud-native security information and event management (SIEM) tool designed for high-level visibility. That’s a lot of big words; translated, it means that if something’s happening on your network – no matter how sneaky – Sentinel is watching.

Armed with artificial intelligence, it detects, analyses, and responds to threats across your business’s entire digital ecosystem. Its key features are:

• AI-Driven Threat Detection: Sentinel is the AI investigator you want on your team, spotting odd patterns and suspicious behaviour before they turn into full-blown incidents.
• Automated Responses: Playbooks within Sentinel allow for automated responses to certain threats, helping your security team stay on top of what matters most.
• Data Collection from Everywhere: Sentinel aggregates data from multiple sources – Microsoft 365, Azure, and other environments – giving your team a 360-degree view of potential threats.
• Threat Hunting: Security analysts can dig into potential vulnerabilities and explore threats proactively, helping prevent issues before they arise.

Ideal For: Organisations that need a “big picture” security monitor. Sentinel is your choice for centralised, scalable threat monitoring across hybrid and multi-cloud environments.

Microsoft Defender for Business – Enterprise-Grade Device Protection for SMEs

Microsoft Defender is more of a boots-on-the-ground solution, focused on protecting individual endpoints – think laptops, smartphones, tablets – from malware, ransomware, phishing and other cyber threats. Defender operates in real-time, identifying threats at the device level. Think of it like a digital bodyguard, protecting devices from exposure.

Defender protects your network through:

• Malware and Ransomware Protection: Defender screens files and applications for malicious activity, guarding against common attack methods.
• Endpoint Detection and Response (EDR): Defender monitors for suspicious behaviours on devices, providing alerts and insights so security teams can act quickly.
• Cross-Platform Compatibility: Defender covers Windows, macOS, Linux, iOS, and Android, ensuring security across device types in your business.
• Simplified Security Management: Helps secure your network quickly with easy-to-use management controls.

Ideal For: SMEs that need to secure their devices. Defender for Business is designed specifically for companies with up to 300 employees, providing cost-effective protection for employees working in the office and remotely.

What are the Differences Between Sentinel and Defender?

Defender Doesn’t Scale

Microsoft Defender for Business is specifically built for businesses with less than 300 employees, so growing businesses may find themselves needing a more scalable solution. For smaller teams, it offers effective, straightforward security for their devices. It’s designed to protect devices from threats like malware and phishing without requiring extensive setup or maintenance.

In contrast, Microsoft Sentinel is geared toward organisations of all sizes, especially those with complex security demands and larger infrastructures. Sentinel’s centralised, high-level monitoring is ideal for enterprises needing to secure multi-cloud or hybrid environments.

Infrastructure-Wide Security vs. Endpoint Security

Sentinel monitors security data across your entire infrastructure, giving you a powerful, scalable solution that protects all your digital assets as your business grows.

Defender only offers endpoint protection, safeguarding each individual device in your network from digital threats. It’s your device-specific shield, blocking attacks before they have a chance to spread.

Threat Hunting is Only Available with Sentinel

With Defender, you get essential protection features like antivirus, firewall, and real-time threat detection – all focused on keeping your endpoints safe. Sentinel, however, dives deeper with advanced analytics, threat hunting, and incident response capabilities. It collects and correlates data from a variety of sources, giving your team more comprehensive threat analysis and investigation tools.

Sentinel Offers a Higher Level of Customisation

Sentinel is highly customisable. It’s relatively quick to deploy – 67% faster than an on-premises SIEM system – and you can create ‘playbooks’ that simplify threat response. Need to isolate an infected machine? You can create a playbook that automatically isolates that machine and locks the associated account by the time the SOC (Security Operations Center) team gets notified about the incident.

So, Which is Better for Your Business?

Do you employ more than 300 staff? If yes, then Sentinel is immediately the better choice.

But, while size is a major factor, your business’s risk profile is also crucial. For instance, a team of five software engineers contracted to solve infrastructure issues for a major credit card company is probably just as big a target as the credit card company itself.

With its ability to monitor across IT environments, Sentinel is a versatile solution for businesses of all sizes, especially those who know they’ll be expanding or have heightened security requirements.

Defender for Business is included in Microsoft 365 Business Premium packages. It’s cost-effective protection that lets your team work securely, but doesn’t include powerful features like threat intelligence, automation and proactive hunting.

Both solutions bring a powerful layer of security, tailored to meet the unique demands of your business’s size and structure. Sentinel takes everything great about Defender for Business and adds additional features that help you detect, investigate and respond to security threats in real time.

Ready to Fortify Your Cyber Security?

Businesses today need robust security measures to stay ahead of evolving threats. Both Sentinel and Defender for Business help defend against threats, and the right choice depends on your business’s current needs and future ambitions. Cyber security is an ongoing journey, and the best defence is one that fits your business like a glove.

At AAG, our experts can help you implement and manage the right solutions for your unique needs, ensuring your business stays secure, compliant, and ahead of evolving threats. Contact us today to find out how we can support you in building a more secure future.