One of the applications of MAC addresses is in the filtering process on wireless networks. Some firms may have more than one MAC address. Some manufacturers, such as Dell, place a unique identifier in the MAC address, which is called the Organizationally Unique Identifier (OUI), and identifies the manufacturer. An example of a MAC address is 30-65-EC-6F-C4-58. The format is six sets of two digits or characters, separated by hyphens. The MAC address is formed in accordance to the rules of the three numbering name spaces, which are managed by the Institute of Electrical and Electronic Engineers (IEEE). During network communication the Address Resolution Protocol (ARP) for the Internet Protocol Version 4 (IPv4) or the Neighbor Discovery Protocol (NDP) for IPv6 translates the IP into a NIC.

The NIC is a computer circuit card that allows a computer to connect to a network. The MAC address is usually assigned by the manufacturer of a Network Interface Controller (NIC), and it is stored in the hardware. Among its applications are the Ethernet, 802.11 wireless networks and Bluetooth. Sometimes it is known as the burned-in address (BIA) or the Ethernet hardware address (EHA). It is used as a network address for most IEEE 802 network technologies. It is a unique identifier for network interfaces. bogstad Posts: 3 Joined: 9.MAC stands for Media Access Control.

Start changing other things and expect to need to reactivate. If you leave everything else the same besides the network card you might get away with it. Unfortunately, I believe that the network card figures prominently on when Microsoft OSes decide if you need to reactivate your license. The right decision is going to be dependent on exactly what you plan to do with the original as well as cloned VM as well as your operating system. (I would probably do a snapshot instead myself.) Hopefully, this gives you some idea of the issues you should consider. On the other hand, if you have software licenses that use your Ethernet cards address to enforce licensing restrictions then you might want to use the same MAC if your were cloning the system before doing updates which you might want to rollback. Even if you only run one VM at a time, it would be like calling your home phone number and if no one was home at your house it would ring at your neighbor if they were home. Under the wrong setup Bridged, Internal, and Host-only will definitely have problems. The only network mode which probably won't have a problem is NAT. If both VMs are ever run at the same time while connected to the same Ethernet, then they and the other machines (real or virtual) connected to the same Ethernet will get very confused. The result of not reinitializing the MAC addresses is that both VMs will have virtual Ethernet cards with the same Ethernet (MAC) address.

What is alternate mac address