ESP8266 Community Forum

Hello all. I am trying to use my esp8266 to discover several WiFi devices (sensor) in my home. I only know these devices MAC address, and I need to send TCP packets to their IP address. Using RPi, I can do that using ethernet and ARP protocol. But I cannot find similar command in ESP8266. Can you guys enlighten me, ideas about how to get list of devices IP address from router (similar like entering 'arp -a' in Windows )? Or can I directly find a device IP address from their MAC Address?

I learned that ARP cache should exist in ESP8266 since it is part of the link layer of internet protocol - it is needed for a device to send packet to other devices in the network. So maybe the question can be more detailed: can I access this ARP cache via ESP8266?