The DCME Package is used for interfacing Digital Circuit Multiplication Equipment (DCME). DCME types are for instance defined by ITU-T Recs G.763, G.767 or G.768. There is a signalling interface defined between DCME and a so-called "International Switching Centre" (ISC). ITU-T Rec. Q.50 defines such an interface. The DCME Package scopes DCME with Q.50 interfaces.