Hi everyone,
I’m having trouble with spacebridge and connecting over time to an IoT device. Here is the configuration:
- Multitech Dragonfly modem with Hologram SIM
- Sets up and connects to the network fine. The Multitech uses the Telit HE910 chipset which works great.
- Set the modem to listen mode with “AT#SL=1,1,2222” to tell it to enable a TCP socket listen on port 2222.
- Run spacebridge setup to map the modem to a local port.
- Connect to the modem. Works great!
- Disconnect from the modem and get “NO CARRIER” as I should.
- Resend the listen command - “AT#SL=1,1,2222”.
Here is where I have a problem. If I don’t connect to the modem again through spacebridge within about 45 minutes, I will get this message from the modem:
#SL: ABORTED
I cannot figure out why, although I would assume some kind of timeout issue. According to the documentation this means the network kicked me off for some reason. If I then reinitialize the socket on the modem and set it back to listen mode the modem seems like it works, but I cannot reconnect to the modem again through spacebridge until I close the spacebridge app and re-run it. This is on a Win7 machine.
I get these odd messages in spacebridge about “remote device has closed the connection” and I will keep getting them until I run it again. I suspect this has something to do with key generation, but since I don’t know why I got kicked off or how to prevent it, I’m kind of stuck.
This problem seems to be unique to hologram. The exact same configuration with a Verizon SIM does not exhibit this behavior, although in that case I had a fixed IP address for the modem. But it never kicked me off the network no matter how long I waited to make the connection.
Questions:
- Why do I get the “#SL: ABORTED” after 45 or so minutes of not linking to the modem?
- How can I prevent the “#SL: ABORTED” from being sent? Is there some kind of periodic activity I need to initiate on the modem to keep the link active while I wait for an incoming connection?
- Why does spacebridge need to be shut down and restarted to fix the problem?
Thank you in advance for any help you can give.
- Rebecca Taylor
Sr. Engineer, Diamond Edge Technology, LLC