NetBIOS over TCP/IP is described in RFC 1001 and RFC 1002. Note that when higher level protocols such as SMB or CIFS are implemented over TCP/IP they are in fact implemented over NetBIOS over TCP/IP.

Table 2. NetBIOS over TCP/IP

7 Application   e.g. Browser Service
6 Presentation Higher level protocols e.g. SMB / CIFS
5 Session Name Service datagram service Session Service
4 Transport UDP TCP
3 Network IP
2 Datalink e.g. IEEE 802.2 e.g. Ethernet II etc
IEEE 802.3 / IEEE 802.5 etc
1 Physical Token Ring / Ethernet etc