What is NetBIOS Name Service (NBNS)?
NBNS is a networking protocol that was made for older systems to allow communication over modern TCP/IP networks. In many cases, NetBIOS is still used in some organizations today, and disabling it could cause disruption in services. It has many of the same functionalities as DNS, which are that it allows for legacy systems to resolve DNS names to IP addresses.
In today’s age, systems with NBNS attacks can be vulnerable to NBNS poisoning attacks, and is typically recommended to be disabled unless absolutely required for business operations.