2 factor authentication

Hello

I know 2 factor authentication configuration.

When I configurate it, all view user need to 2 factor authentication.

I want to user 2 factor authentication for some users.

Example:

For external users using 2 factor authentication (domain and radius).

For internal users only using domain authentication.

How to configre it?

vCenter, vSphere: 5.5

View: 5.3

Please help me.

Thanks.