Multi-factor authentication requires two or more different kinds of evidence to sign in: something you know, something you hold, or something you are. It protects administrator accounts for video and access systems, where a stolen password alone would otherwise expose every camera and door.
MFA is standard on business email and rare on a video recorder. The accounts that can view every camera or open every door deserve it more.
Choosing a second factor
Authenticator apps and hardware security keys resist phishing. Text messages are better than nothing but can be intercepted or redirected through a carrier attack.
The part people forget
Enrollment and recovery decide whether MFA holds. If a support line resets an account after one phone call, the factor can be bypassed without breaking anything.
Related:Glossary: Access control systemGlossary: Video management system