The Virginia Plan (also known as the Randolph Plan, after its sponsor, or the Large-State Plan) was a proposal by Virginia delegates for a bicameral legislative branch. The plan was drafted by James Madison while he waited for a quorum to assemble at the Constitutional Convention of 1787.
Virginia's Plan was based on population. The larger states favored this plan because it would give them more representation in Congress.
The Full Faith and Credit Clause deals with legal proceedings between states. Full Faith and Credit shall be given in each State to the public Acts, Records, and judicial Proceedings of every other State.