The Address Resolution Protocol (or ARP) is a very important part of IP networking. ARP is used to connect OSI Layer 3 (Network) to OSI Layer 2 (Data-Link). This means to communicate with any device on your network, you must have the Ethernet MAC address for that device. If the device is not on your LAN, you go through your default gateway (your router). In this case, your … [Read more...] about How To Clear or Flush ARP Cache in OS X Yosemite