Internet access system using voiceband modems and out-of-band transmission over local loop lines

Abstract From the Canadian patent

Telephone service subscribers who are connected to a telephone network via local loop lines to local telephone switches are also connected to a data network without communication through the local telephone switches. The system has frequency translator devices for translating send and receive voiceband frequency signals used by voiceband data modems to different frequency bands above the voiceband used by the telephone network. The voiceband modems at the subscriber premises maintain a connection in the presence of transient signals caused by on-hook and off-hook activity of voiceband subscriber equipment. The system also has data network bridge equipment connected between the local …