  
PSS ID Number: Q136403
Article last modified on 09-09-1996
 
3.10 3.50 3.51  3.11
 
WINDOWS
 

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The information in this article applies to:
 
 - Microsoft Windows NT operating system version 3.1
 - Microsoft Windows NT Advanced Server version 3.1
 - Microsoft Windows NT Workstation versions 3.5 and 3.51
 - Microsoft Windows NT Server versions 3.5 and 3.51
 - Microsoft TCP/IP-32 for Windows for Workgroups, versions 3.11, 3.11a,
   and 3.11b
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SUMMARY
=======
 
The User Datagram Protocol is an unreliable, connectionless oriented
protocol that uses an IP address for the destination host and a port number
to identify the destination application.
 
The UDP port number is distinct from any physical port on a computer such
as a COM port or an I/O port address. The UDP port is a 16-bit address that
exists only for the purpose of passing certain types of datagram
information to the correct location above the transport layer of the
protocol stack.
 
MORE INFORMATION
================
 
UDP ports are not the same as TCP ports, though TCP and UDP may use the
same port number in certain instances. The UDP ports can receive more than
one message at a time, and they are identified by "well known" port
numbers. The following is a listing of some of the more common "well known"
UDP ports:
 
Port   Keyword       Description
----   -----------   ------------------------------
 
15     NETSTAT       What is the network status
 
53     DOMAIN        Domain Name Server
 
69     TFTP          Trivial File Transfer Protocol
 
137    NETBIOS-NS    NetBIOS name service
 
138    NETBIOS-DGM   NetBIOS datagram service
 
161    SNMP          SNMP network monitor
 
The UDP specification is defined in RFC 768.
 
Note: The NETBIOS-NS (NetBIOS name service) port value can be configured to
accommodate products from specific vendors. The Registry parameter that
controls this value is NameServerPort.
 
For additional information on the NameServerPort parameter, please see the
following article(s) in the Microsoft Knowledge Base:
 
   ARTICLE-ID: Q120642
   TITLE:      TCP/IP & NBT Configuration Parameters for Windows NT 3.5
 
REFERENCES
==========
 
"Inter-Networking with Microsoft TCP/IP Using Microsoft Windows NT,
Participant's Workbook," P/N 4275A, Appendix A, page 222.
 
"TCP/IP Illustrated, Volume 1, The Protocols," W. Richard Stevens,
pp 6,7,12,13, Addison-Wesley, 1994.
 
KBCategory: kbnetwork
KBSubcategory: nttcp
Additional reference words: ppp endpoint connection
 
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Copyright Microsoft Corporation 1996.


 
