I have registered in SF connected application, let say XY. This was done to accomplish SSO scenarios.
If there is integration on Partner API level as described, is it possible then to call from XY application SF web service API without OAuth 2.0 protocol ? I want to call SOAP API by invoking login method with user name and password and then to use obtained session id in further communication with that API.
Why ? We are having code (XY application) that is working perfectly on that way and I want just to add for SSO scenarios OAuth 2.0 protocol over connected app trust relationship.
Is that possible, or I have to move all of the calls to SF over OAuth. This mean to use access token instead of present session id.