may be compromised there are however steps that may be taken to ensure proper operation of the invention these include for example 1 ordering a direct inward dial connection and instructing the phone company to avoid a two wire connection for that setup 2 obtain a direct t1 to the interexchange carrier for example a 34 1 800 34 number and obtaining an isdn pri connection as it will always support four wire for both call origination and call answer by way of illustration consider a call originated by the computer 15 and cellular modem 16 to the standard pstn modem 32 the established communication link will pass through the cellular phone 17 to the cell tower 18 through the cellular network switch 12 across link 22 to the msc cellular modem 20 and to the connected modem 24 via rs 232 connection 37 across link 26 and back through the cellular network switch 12 to the pstn 34 and ultimately across the two wire link 36 to modem 32 as will become clear from the description that follows the cellular modem 16 and the msc cellular modem 20 will connect and startup in accordance with the communication protocol of the present invention however since the established communication link that passes from modem 24 to modem 32 passes through a pstn 34 and a hybrid converter then the communication protocol of the present invention will not be adequately supported accordingly and in accordance with the invention the modems 24 and 32 will identify this situation and will connect and.