Windows Internet Name Service(WINS)

1. Windows Internet Name Service(WINS) Chapter 16

2. Windows Internet Name Service(WINS) • Network Basic Input/Output System (NetBIOS) • provides commands and support for network name registration and verification. • session establishment and termination. • reliable connection-oriented session data transfer. • unreliable connectionless datagram data transfer. • adapter monitoring and management. • NetBIOS over TCP/IP (NetBT) the operation of the NetBIOS protocol over the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP) of the TCP/IP protocol stack.

3. NetBT Name Service Messages • Name Query Request • Name Query Response • Name Registration Request • Name Registration Response • Wait Acknowledgment • Name Refresh Request • Name Release Request • Name Release Response

4. NetBT Name Service Messages • Name Service header Fixed length • (12 bytes long) • Question entries Variable legth • Answer RRs Variable length • Authority RRs Variable length • Additional RRs Variable length

5. Name Service header • Transaction ID > 2-byte • Flags > 2-byte • Question Entry Count > 2-byte • Answer RR Count > 2-byte • Authority RR Count > 2-byte • Additional RR Count > 2-byte

6. The Flags field in the Name Service header • Request/Response > 1-bit • Operation Code > 4-bit • Authoritative Answer > 1-bit • Truncation > 1-bit • Recursion Desired > 1-bit • Recursion Available > 1-bit • Reserved > 3-bit • Return Code > 4-bit

7. NetBIOS Name Representation • The 16-character NetBIOS name is converted into a 32-byte ASCII representation. • The period (.) character and the NetBIOS scope identifier are appended to the 32-byte ASCII representation of the NetBIOS name. • The resulting name is then encoded using length-value format according to the rules for • fully qualified domain names (FQDNs) in DNS Name Query Request messages. Creating the DNS form of a NetBIOS name for NetBIOS name service messages involves the followingsteps:

8. Question RR Format Question entry format • Question Name • Question Type • Question Class RR format in NetBIOS name service messages • RR Name • Record Type • Record Class • Time to Live • Resource Data Length • Resource Data

9. Question RR Format Format for General Name Service RRs • RR Name • Record Type • Record Class • Time to Live • Resource Data Length • Data Flags • IP Address Format of the RDATA flags field • Group Flag • Owner Node Type • Reserved

10. Question RR Format

11. Question RR Format

12. WINS Client and Server Message Exchanges • Resolving NetBIOS names to IP addresses • Registering NetBIOS names • Renewing NetBIOS names • Releasing NetBIOS names This section describes common message exchanges between WINS clients and servers for the following:

13. Resolving NetBIOS Names to IP Addresses

14. Resolving NetBIOS Names to IP Addresses

15. Registering NetBIOS Names

16. Resolving NetBIOS Names to IP Addresses

17. Registering NetBIOS Names

18. Refreshing NetBIOS Names

19. Refreshing NetBIOS Names

20. Releasing NetBIOS Names

21. Releasing NetBIOS Names

22. Summary fixed-size variable-sized Name Query Request Name Query Response messages WINS-based NetBIOS name resolution Name Query Response Name Registration Request Name Registration Response NetBIOS name registration WACK Name Registration Response Name Refresh Request Name Release Request NetBIOS name refresh NetBIOS name release Registration Response Name Release Response