|  1 |    initial version    |  
It's not malicious; it's just normal ARP traffic you'll find on any IPv4 network. The host with the Sercomm Corporation OUI (D4-21-22) is attempting to find out which host has a particular IP address, and this is the mechanism by which it accomplishes that.
See also: https://en.wikipedia.org/wiki/Address_Resolution_Protocol
    |  2 |    No.2 Revision    |  
It's not malicious; it's just normal ARP traffic you'll find on any IPv4 network. The host with the Sercomm Corporation OUI (D4-21-22) is attempting to find out which host has a particular IP address, and this is the mechanism by which it accomplishes that.
See also: https://en.wikipedia.org/wiki/Address_Resolution_Protocolthe Wikipedia article on ARP.