Element Index for attachment control. Specifies the type of class map element to relate with the class map. When type is macAce(1), the index of diffServClassMapAttachCtlElementIndex is the index of diffServMacAceEntry. When the type is ipAce(2), the index of diffServClassMapAttachCtlElementIndex is the index of diffServIpAceEntry. When the type is acl(3), the index of diffServClassMapAttachCtlElementIndex is the index of diffServAclEntry. When type is ipv6Ace(4), the index of diffServClassMapAttachCtlElementIndex is the index of diffServIpv6AceEntry.