NetBIOS Broadcasts

When a computer seeks to resolve a NetBIOS name to an IP address, it sends a NetBIOS broadcast. Because the name-resolution request takes the form of a broadcast message, it is sent to all nodes on the local subnet (the subnet being a particular segment on a routed network).

For example, imagine a computer named Kirk wants to send data to a computer named Spock. Kirk broadcasts that it would like to send data to Spock but does not know Spock’s IP address. When Spock hears this broadcast (as do all nodes on the subnet), Spock sends a response providing Kirk with the IP address. Kirk can now proceed with establishing a network session with Spock and transferring data as needed.