单选题An architectural design company with 45 employees has their office located within 5 kilometers oftheir disaster recovery center. They have an IBM System Storage N6040 installed at bothlocations. In this customer environment what protocol would be used 

An architectural design company with 45 employees has their office located within 5 kilometers oftheir disaster recovery center. They have an IBM System Storage N6040 installed at bothlocations. In this customer environment what protocol would be used for disaster recovery？（）