Our friend trying to set up our modem in Germany. He provided us APN name of the sim card. We saved the APN configuration on modem. Then the modem established gprs connection, got a dynamic ip address then connected to our server machine as TCP client.
From our server side, we obtained the ip address of the modem. Then we try to connect to that ip address over TCP port 3000 but we can not establish any connection.
Does anyone know about a similar issue with T-Mobile sim cards? Should we obtain a static ip address or should we use a different apn name? Or do they block the inbound port number of 3000 which we try to connect? Or do they have any NAT rule behind the modem ip address?
Currently used Apn names : both “internet” and “internet.t-mobile” were tried.
Module configuration: Airprime Q2687RD, R7.46 FW