Method and system for dynamically switching multiple CA systems in real time

The invention discloses a method and system for dynamically switching multiple CA systems in real time. The method for dynamically switching the multiple CA systems in real time comprises the steps that options of the multiple CA systems are loaded on a player in advance, and information of the CA systems is preset in an adapter; when any CA system is selected by a user, whether a plug-in of the selected CA system is currently installed in the adapter or not is detected; if not, the corresponding plug-in is sent to the adapter through the player; the adapter performs verification operation onsignature data of the plug-in; if the verification succeeds, the adapter server applies for activation to an operator server corresponding to the CA system according to the intelligent card ID and theequipment ID; if the activation succeeds, activation success information is sent to the adapter; and the adapter installs the selected plug-in of the CA system, deletes the original plug-in, descrambles a data stream and tran