Who is responsible for what.
THE PRINCIPLE
The provider secures the infrastructure.
You secure what you put on it and who can reach it.
WHAT THE PROVIDER HANDLES
Physical security Hardware The underlying platform Their own network
WHAT YOU HANDLE
Your accounts and who has access Your configuration Your data Your own backups Whatever you install
WHERE THE LINE SITS
It differs by service type.
The more managed the service, the more the provider handles.
WHY THIS MATTERS
Most cloud incidents are customer-side: exposed storage, weak credentials, misconfiguration.
Not provider failures.
WHAT PEOPLE ASSUME WRONGLY
That using a reputable provider means their data is secure.
Their infrastructure is secure. Your configuration may not be.
WHAT TO ESTABLISH FOR EVERY SERVICE
Exactly which side of the line each item sits on.
WHAT TO ASK THE PROVIDER
What they do, and what remains yours.