IT and cyber security becomes more complex over time. The sun also rises. Traditional preventative security measures – firewalls, endpoint protection, Identity and Access Management (IAM) controls – are no longer adequate on their own to defend against cyber threats.
The logical approach to fixing this has been to use a Security Information and Event Management (SIEM) platform to combine all the alerts and data. But for those organizations with the means to use SIEM, the result has often been a deluge of data of wildly varying fidelity from a multitude of controls. That’s led to a further development: Endpoint Detection and Response, and Managed Detection and Response.
https://www.withsecure.com/us-en/expertise/resources/siem-edr-mdr-in-house-or-managed-service