Service Name and Transport Protocol Port Number Registry

Last Updated

  • 2026-10-22

Expert(s)

  • TCP/UDP: Joe Touch; Eliot Lear, Kumiko Ono, Wes Eddy, Brian Trammell, and Michael Scharf
  • SCTP: Michael Tuexen
  • DCCP: Eddie Kohler and Yoshifumi Nishida

Reference

  • RFC 6335: Internet Assigned Numbers Authority (IANA) Procedures for the Management of the Service Name and Transport Protocol Port Number Registry

Note

Service names and port numbers are used to distinguish between different services that run over transport protocols such as TCP, UDP, DCCP, and SCTP.

Service names are assigned on a First Come First Served basis, as described in RFC 6335.

Port numbers are divided into three ranges, with their uses and assignment procedures specified in Section 8.1.2 of RFC 6335:

The registration procedures for service names and port numbers are specified in RFC 6335, while the registration policies referenced above are defined in RFC 8126.

Assigned ports both System and User ports SHOULD NOT be used without or prior to IANA registration.

Assignment of a port number does not in any way imply an endorsement of an application or product, and the fact that network traffic is flowing to or from a registered port does not mean that it is "good" traffic, nor that it necessarily corresponds to the assigned service. Firewall and system administrators should choose how to configure their systems based on their knowledge of the traffic in question, not whether there is a port number registered or not.

Registration Forms

Available Formats

Service Name Port Number Transport Protocol Description Assignee Contact Registration Date Modification Date Reference Service Code Unauthorized Use Reported Assignment Notes
custix 528 tcp Customer IXChange Ferdi Ladeira Ferdi Ladeira 2022-01-25
custix 528 udp Customer IXChange Ferdi Ladeira Ferdi Ladeira 2022-01-25
norp 1528 tcp Not Only a Routeing Protocol nyantec Mikael Voss 2021-04-07
norp 1528 udp Not Only a Routeing Protocol nyantec Mikael Voss 2016-09-13 2021-04-07
norp 1528 sctp Not Only a Routeing Protocol nyantec Mikael Voss 2021-04-07
ncr-ccl 2528 tcp NCR CCL

IANA assigned this well-formed service name as a replacement for "ncr_ccl".
Amitava Dutta Amitava Dutta
ncr_ccl 2528 tcp NCR CCL Amitava Dutta Amitava Dutta This entry is an alias to "ncr-ccl". This entry is now historic, not usable for use with many common service discovery mechanisms.
ncr-ccl 2528 udp NCR CCL

IANA assigned this well-formed service name as a replacement for "ncr_ccl".
Amitava Dutta Amitava Dutta
ncr_ccl 2528 udp NCR CCL Amitava Dutta Amitava Dutta This entry is an alias to "ncr-ccl". This entry is now historic, not usable for use with many common service discovery mechanisms.
jboss-iiop 3528 tcp JBoss IIOP
jboss-iiop 3528 udp JBoss IIOP
xmpp-bosh 5280 tcp Bidirectional-streams Over Synchronous HTTP (BOSH) Peter Saint-Andre Peter Saint-Andre 2009-11-25
5280 udp Reserved
undo-lm 5281 tcp Undo License Manager Undo Ltd Edward Moffett 2010-04-19 2019-01-25
5281 udp Reserved
transmit-port 5282 tcp Marimba Transmitter Port Johan Eriksson Johan Eriksson 2002-04
transmit-port 5282 udp Marimba Transmitter Port Johan Eriksson Johan Eriksson 2002-04
5283-5297 Unassigned

Contact Information

Name Organization Contact URI Last Updated
Amitava Dutta Amitava.Dutta&woodbridgenj.ncr.com
Edward Moffett Undo Ltd office.manager&undo.io 2019-01-25
Ferdi Ladeira f.lad.mail&gmail.com 2022-01-25
Johan Eriksson johan&marimba.com 2002-04
Mikael Voss mvs&nyantec.com 2017-04-18
nyantec info&nyantec.com 2017-04-18
Peter Saint-Andre stpeter&stpeter.im 2009-11-25
Undo Ltd office.manager&undo.io 2019-01-25