Repeatable_Read_and_Serializable_isolation_level

Bruce's lecture on MVCC: In 9.1, we have repeatable read. This is old "Serializable". Now serializable adds another condition. When a conflict is detected, the transaction will be aborted. This will be covered by Friday's lecture on "Serializable Snapshot Isolation". I need to listen to it to have better idea how to support new isolation level.