WIZ550S2E TCP not working on corporate network. loses first 16 bytes of data.

Question

Hi, I am new to the forum, but have been working with the WIZ550S2E with version 1.4.0 firmware for a few months. I am using the module in 2 application in different modes, both use DHCP. Mode #1 UDP in Data Mode Mode #2 TCP in Command mode, using AT+NSEND On small networks both modes work fine. On a corporate (domain) network with a Windows DHCP server Mode #1 works fine but in Mode #2 I am losing the 1st 16 bytes of the data packet. This Wireshark trace shows the problem: image1190×667 59.2 KB This trace shows what should be in the data block: image1454×815 162 KB Does anyone have any suggestions as to what is causing this data loss? Thanks John

jcomfort · Answer

A follow on to this earlier post. Command mode UDP messages have the same problem. OK in data mode, but when sending on a corporate network we again lose the first 16 or 17 bytes in UDP using AT+NSEND any suggestions? thanks John

austin · Answer

Hi John, Could you share the ‘*.pacp’ file that captures the problem?