What this means
The IEEE assigned the MA-S block 70B3D56EE to HANKOOK CTEC CO,. LTD.. Every network interface they manufacture under this block has a MAC address beginning with these digits, followed by a unique per-device identifier. If a device on your network shows a MAC starting 70:B3:D5:6E:E, it is HANKOOK CTEC CO,. LTD. hardware.