SOC for Microsoft 365 and Sentinel: what matters

A SOC for Microsoft 365 and Sentinel environments correlates signals from Entra ID, Defender XDR, Exchange Online and Azure in one detection layer. It responds 24/7. Analysts, playbooks and documented response provide the operational value beyond the licence.

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How this compares to neighbouring topics

This page describes how a SOC secures a Microsoft 365 and Sentinel environment. For fundamentals see What is a SOC. For differences from pure managed services, see SOC vs. MDR and MDR vs. Managed SIEM. What is XDR explains the underlying platform category. For CrowdStrike or Elastic-based environments, see the counterparts under SOC on CrowdStrike Falcon and SOC on Elastic Security. For pricing details see SOC cost Switzerland.

Why Microsoft 365 environments deserve their own chapter

Most attacks against Swiss SMEs today begin inside Microsoft 365. Compromised Entra ID identities, token theft, business email compromise and OAuth consent abuse are the norm, not the edge case. Running that environment without 24/7 oversight means you see signals only when a customer complains.

Which signals a SOC correlates

  • Entra ID: risky sign-ins, impossible travel, legacy auth, MFA fatigue
  • Defender XDR: endpoint, identity and cloud-app alerts on a single timeline
  • Exchange Online: inbox rules, auto-forwarding, suspicious delegations
  • Azure and Sentinel: resource changes, role assignments, data exfiltration
  • OAuth apps: new consents, overprivileged third-party applications

What documented response looks like in practice

  • Immediate lockout of compromised accounts and token revocation
  • Endpoint isolation via Defender for Endpoint per playbook
  • Rollback of malicious inbox rules and forwarding settings
  • Revocation of harmful OAuth consents with audit trail
  • Handoff to your IT for recovery, coordinated by the SOC

Typical pitfalls

Not every Microsoft 365 licence includes the telemetry you need. E3 without Defender add-ons delivers far less than E5. Sentinel becomes an empty log store without data connectors. And a service that only forwards alerts from the Defender portal without responding covers visibility, not response. See SOC KPIs MTTD and MTTR for details on alert distribution.

Cost drivers

Cost for a managed SOC with Microsoft 365 and Sentinel follows endpoints, identities, data sources, data volume, response scope and onboarding; vendor licences come on top. Full cost logic under SOC cost Switzerland.

Rule of thumb

Sentinel without analysts is an expensive log archive. Sentinel with a SOC is a response platform.

Frequently asked questions

Do we need an E5 licence for a SOC?

You do not necessarily need E5. E5 provides the most complete telemetry, but a SOC can run meaningfully on E3 plus Defender add-ons. The connected signals determine the licence's suitability.

Does Microsoft Sentinel replace a classic SIEM?

Sentinel replaces a classic SIEM in many environments. Sentinel is a cloud-native SIEM with XDR integration. Without a SOC or MDR, it remains a platform without response.

How long does onboarding for a Microsoft 365 environment take?

Onboarding takes several weeks. Data connector setup, playbook tuning, access delegation and baseline calibration account for that time. Signing in takes only a small part of it.

What happens if an account is compromised at 3 a.m.?

A serious provider locks account and tokens per playbook immediately, documents the case and hands over recovery coordination in the morning. Without a 24/7 SOC, nothing happens until the next business day.

Can a SOC operate our Sentinel, or do we have to hand it over?

Both models work. Co-managed Sentinel keeps ownership with you while the SOC takes over detection engineering and response. Fully managed lets the provider run Sentinel in its own tenant.

Continue reading in this cluster
What is a SOC? Definition, tasks and structure
A Security Operations Center (SOC) is a team of people, processes and technology. It monitors an organisation's IT and OT environment around the clock, detects attacks and coordinates the response. A SOC is not a piece of software; it is an operating unit.
What is XDR? Extended Detection and Response explained
Extended Detection and Response (XDR) is a detection platform that correlates telemetry from endpoint, identity, email, cloud and network in one data model. XDR replaces many functions of a classic SIEM, but it does not replace a team. Only combined with a SOC or MDR does it turn into security.
SOC, SIEM, EDR, XDR, MDR: the terms explained
SOC is the function; SIEM, EDR and XDR are tools; MDR is a service. The label matters less than whether response happens and in whose mandate. At ANOMAL, SOC as a Service covers detection and response and is often called MDR; a managed SIEM is part of the SOC with analysts and response in the mandate. Customers keep their existing tools.
What a SOC costs: cost drivers, pricing models, in-house or service
SOC costs arise from the response scope first, not the platform licence. What counts are endpoint and identity counts, log sources and data volume, the response scope you choose, onboarding and licences. Swiss providers rarely publish prices; offers differ widely by scope. Your own calculation starts by holding the cost drivers against your organisation.
Look up short definitions in the glossary

Related terms