1)master control switcher,主控切换台2)Master controller election and handover,主控选举和切换3)MCR/ECR transfer switch,主控/应控切换开关4)MCR/LL transfer switch,主控/就地切换开关5)The Controlling MSC on which the call was originally established,发起切换的主控MSC6)master station,主台，主控台，总台
