Hi Sami,
IFD itself is a mode of authentication to CRM out of the specified types of authentication.
1. Outlook Client
2. On-Premise
3. IFD/partner-hosted.
If laptop is not in the domain 2 options prevail
1. connect to the domain and then logon to CRM via On-premise(web) or outlook client.
2. Or IFD (web).
http://msmvps.com/blogs/larrylentz/archive/2011/06/22/reconfiguring-the-crm-2011-outlook-client-for-ifd.aspx
please check the above post for reference.
hope this answers ur question.
crmdev2011