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MSSP (Managed Security Service Provider)
Definition
An MSSP is an external service provider that delivers cybersecurity monitoring and management as an ongoing service.
A Managed Security Service Provider (MSSP) is an external service provider delivering cybersecurity monitoring, management and response as an ongoing service. According to MarketsandMarkets, the global MSSP market is growing to $53 billion by 2028, driven by the cybersecurity skills shortage and increasing threat complexity.
How does an MSSP work?
An MSSP takes over security tasks that an organisation cannot or does not want to perform internally. Typical services include: 24/7 security log monitoring, firewall and IDS/IPS management, vulnerability scanning and patch management, incident detection and initial response, and compliance reporting. The MSSP operates from its own SOC using shared platforms and processes for multiple clients.
Difference between MSSP and MDR
A traditional MSSP is predominantly reactive: the team monitors systems, reports alerts and manages security infrastructure. MDR is proactive: the team actively hunts threats, analyses suspicious behaviour and takes automated or manual response actions to neutralise threats. MDR goes deeper and faster than traditional MSSP services. Many organisations are transitioning from MSSP to MDR for better protection.
Impact on organisations
Establishing an internal SOC costs 2-5 million euros annually on average. Finding and retaining qualified security staff is a major challenge. An MSSP or MDR provider offers enterprise-grade security at a fraction of the cost. NIS2 requires adequate monitoring and detection capabilities, achievable for many organisations only through an external provider. DORA sets specific requirements for third-party ICT service management.
Protection
Choose a provider with proven experience in the specific sector and region. Evaluate technology stack, detection capabilities and response times. Ensure clear SLAs with measurable KPIs. Require transparency about detection rules and incident handling.
How DEFION helps
DEFION delivers MDR services that go beyond traditional MSSP. The 24/7 SOC team combines Managed Threat Detection, Managed Threat Hunting and MXDR for proactive security.