A (mostly legacy) protocol that was originally developed to only run over LAN. When TCP/IP became the standard networking protocol, NetBIOS was adapted to run over TCP/IP via the NetBIOS over TCP/IP otherwise known as the NBT protocol.

Port 139 facilitates communication for file and printer sharing as well as for remote access between devices on a network. Port 445 (SMB) is now more commonly used for file and printer sharing on common networks.

nbtscan <IP>

Note it provides the IP, hostname, server, user and MAC address.

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