Method of Transmitting a Single Lower Speed Data Channel on a 64 kbit/s Data Stream - Data Communication Networks - Transmission, Signalling and Switching, Network Aspects, Maintenance and Administrative Arrangements (Study Group VII) 2 pp
that Recommendation X.50 sets out the fundamental parameters for a multiplexing scheme .ar the interworking of networks where at least one makes use of the &bit envelope structure or of the four 8-bit
envelopes grouping;