Ethernet network wake up problem

Sorry for my English, Ill try to explain my problem…

I use vim1 with apk that reads arduino signal inputs connected to vim USR-K3 TTL UART to Ethernet
All works, but after vim sleep somehow there is no receiving communication.
apk see connection but nothing happens. by unplugging Ethernet cable connection is lost. and plugging back all works again!
I have tried on 2 different vims with different roms.

so far I have figured out that I need after sleep trigger Ethernet cable to get all working again
Or I`m doing something wrong…