Use multiple arduino's and connect them to internet

Good evening,

I have an arduino with 4 or 5 sensors and a rfid module. When I approach the card to the reader this should be able to operate the sensors. What I would like to do, however, and do not put the codes of RFID cards that can operate the sensors in the source code of arduino, but I want the Arduino communicate (possible via LAN) to a PC or a raspberry / beaglebone / udoo that is connected to internet and make the request and to a cloud server if the card is enabled or not Is it possible to do such a thing?

I can have multiple arduino.

Yes.

Might be able to do all of that with a single ESP8266 based board, depending what the "other sensors" are.

Google something like "ESP8266 RFID Arduino" (images). Leo..