Our current SharePoint 2010 environment includes a custom claims provider hooked into ADFS, allowing partners of ours to log in with their our network credentials if we have added their LDAP via an IDP in ADFS. We also allow Google and Linked In log ins. While this has been a pretty amazing system for us, we have a new directive to get out of the server and app hosting business, and move everything to Office 365. Exchange is already hosted there.
We would like to mirror the same authentication system we have in our current system, so we won't have to go through losing permissions on our existing external users. We have about 3000 of them. I am pretty sure I know this isn't possible, due to the fact everything I've seen about it, the user already has to exist there. Whether that be AD, or a Windows Live account for external users. Can anyone point me to a definitive answer on this one?
Once I have that definitive answer. What are my alternatives? Is there any way I can map these external users to anything during the migration that would allow all of those user permissions to be migrated?
Jeff Scroggin