Decision guide

SIEM vs Managed SIEM vs MDR

SIEMManaged SIEMMDR
What it is Software for collecting logs, correlating events, and supporting investigations.A service that manages, hosts, tunes, or monitors a SIEM environment.A service that investigates and responds to threats, often using SIEM, EDR, identity, cloud, and network data.
Who operates it Usually the buyer’s security or IT team.Shared between the provider and buyer, or mostly provider-operated.Provider analysts own more of the investigation and response workflow.
Main buyer problem Need centralized logging, correlation, retention, and visibility.Have logs and alerts but lack time or expertise to tune and operate SIEM well.Need 24/7 investigation and response capacity, not only a place to store alerts.
Main caution A SIEM alone does not provide analysts or response.Managed SIEM may still leave containment and incident response with the buyer.MDR may not replace compliance log retention or full SIEM ownership.

Buyer takeaways

  • Start with the work you need done, not the acronym.
  • If alert investigation is the bottleneck, MDR may be more relevant than managed SIEM.
  • If log retention, data cost, and detection tuning are the bottleneck, managed SIEM may be the better starting point.