Is padding added by EM12G hardware or firmware while sending ipv4 packets with ip total length < 46 bytes?

Technical Subjects
1

Hi all,

In wired connections the NIC controller takes care of adding padding bytes if ethernet packet size is less than 64 bytes (IP total length < 46 bytes).
How this scenario is handled in cellular modem? Does the modem add any padding bytes before sending?

I am using gobinet & usbnet drivers & they never add any padding as per my code flow understanding.

Thanks,
Sanjib

2

Hi,
Thanks for your query in Quectel forums.
Are you testing and verifying in the TCP protocol?
Thanks.

3

I am sending simple ping packets < 46 bytes (ip total length) from my gateway (having EM12G modem as cullular uplink) to a server (with wired connection).
How is this working with cellular modem?
I know NIC controllers add padding so that the receiving end doesn’t declare them as runt packets & then drop.
Who takes care of this padding part with cellular modem?