What is a managed security service provider (MSSP)?

A managed security service provider (MSSP) continuously monitors an organisation's systems — networks, servers, staff devices — from a 24/7 security operations centre, and responds when something looks wrong. The subscription typically covers:

• around-the-clock monitoring and alerting
• threat detection across the internal network and endpoints
• incident triage and response
• security tooling the provider runs on your behalf

The model assumes there is an internal estate worth watching: office networks, servers, fleets of managed devices. That is exactly what medium and large organisations have, and an MSSP is often the right answer for them. A small business running a website, cloud email and a few laptops mostly has no internal network to monitor — the public-facing surface is the story, and that is the job of a scanning service rather than a security operations centre. An MSSP is not a scaled-down consultancy; it is a different product, and at 1–30 staff usually the wrong-shaped one.