Trying to communicate using MQTT using Micropython on Xbee3 Cellular Modem.
It appears that Micropython’s usocket library sends with TCP Header Option- Maximum Segment Size(MSS) that is very low (less than 50). Such low values are considered a security vulnerability and discarded by Layer 4 appliances and firewalls causing failures and problems.
Can someone please let me know how I can update the TCP Options Header of MSS in Micropython, / usocket library or even outside?
Linking below information for TCP MSS pointers and the IETF standards for additional pointers on TCP MSS:
https://blog.apnic.net/2019/07/31/tcp-mss-values-whats-changed/