Simulating RNDIS call with a BG95M3

Hey!
I’m using BG95M3 as modem to provide internet towards Linux/Windows host. From the modem itself I can ping/TCP stream (in both 2G and NB-IoT RATs) but when I try to do PPP from my hosts, it’s failing.

On the other hand, for RNDIS call, looks that AT+QCFG=“usbnet”,3 command isn’t understandable by the BG95 device.
What am I doing wrong? Can you anyways lead me to proper guidelines to do tethering via this kind of device?

Thanks in advance!
Alfredo

Hi,

I managed to connect my PC via PPP towards the BG95 module. I dial up properly and Internet connection looks OK, but while browsing it’s failing. As I see in pcap, there a lot of TCP retransmissions. I wonder whether the device is sending towards the PC properly all the traffic.

Is there any special configuration to be done upfront in my BG95?
Thanks!

Hi,

Have you set APN before dial? pls following screen shot and try once again,
May this will help you a lot :slight_smile:

Hi! Yes, APN is selected, and actually I can browse, slowly, but I can. There is data consumption.
Strange behavior is that for instance a recurrent ping towards Google (8.8.8.8) is working until I open Chrome and start browsing. So I was thinking on some kind of prioritization of traffic in the device itself.

Again, that’s quite tricky scenario.

Thanks!
Alfredo

Hi,
We had similar issue and it turned out to be an MTU issue. The Global IoT subscription with the operator had a limited MTU of 1374 (3GPP std states 1368 bytes MTU when transport network has a limited IP MTU of 1500 bytes to avoid risk of IP fragmentation). We defined ppp MRU and MTU of 1368 and the file transfers work fine now.
/Johan

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