def type_number(source_list):
    """Returns the Ethernet type, byte 12 & byte 13"""
    output = "IP Protocol "
    if source_list[12] == "08" and source_list[13] == "00":
        return output + "(IPv4)"
    elif source_list[12] == "86" and source_list[13] == "DD":
        return output + "(IPv6)"
    elif source_list[12] == "08" and source_list[13] == "06":
        return output + "(ARP)"
    else:
        return output