Ju,
These are not MAC address but rather Client IDs generated by the operating system running on the individual devices.
From the RFC 2131:
DHCP defines a new 'client identifier' option that is used to pass an
explicit client identifier to a DHCP server. This change eliminates
the overloading of the 'chaddr' field in BOOTP messages, where
'chaddr' is used both as a hardware address for transmission of BOOTP
reply messages and as a client identifier. The 'client identifier'
is an opaque key, not to be interpreted by the server; for example,
the 'client identifier' may contain a hardware address, identical to
the contents of the 'chaddr' field, or it may contain another type of
identifier, such as a DNS name. The 'client identifier' chosen by a
DHCP client MUST be unique to that client within the subnet to which
the client is attached. If the client uses a 'client identifier' in
one message, it MUST use that same identifier in all subsequent
messages, to ensure that all servers correctly identify the client.
I guess that we would need to consult the operating system's technical information to find out what is the process of generating the respective Client ID.
Best regards,
Peter
