Service Name and Transport Protocol Port Number Registry

Last Updated
2026-08-17
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
[RFC6335]
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 process, as
documented in [RFC6335].

Port numbers are assigned in various ways, based on three ranges: System
Ports (0-1023), User Ports (1024-49151), and the Dynamic and/or Private
Ports (49152-65535); the different uses of these ranges are described in
[RFC6335]. According to Section 8.1.2 of [RFC6335], System Ports are 
assigned by the "IETF Review" or "IESG Approval" procedures described in 
[RFC8126]. User Ports are assigned by IANA using the "IETF Review" process, 
the "IESG Approval" process, or the "Expert Review" process, as per 
[RFC6335]. Dynamic Ports are not assigned.

The registration procedures for service names and port numbers are
described in [RFC6335].

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

************************************************************************
* PLEASE NOTE THE FOLLOWING:                                           *
*                                                                      *
* 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.                                                   *
************************************************************************

Request an Assignment
  [https://www.iana.org/protocols/apply]

Available Formats

CSV

XML

HTML

Plain text
Service Name Port Number Transport Protocol Description Assignee Contact Registration Date Modification Date Reference Service Code Unauthorized Use Reported Assignment Notes
n2nremote 1685 tcp n2nremote [Kin_Chan_2] [Kin_Chan_2]
n2nremote 1685 udp n2nremote [Kin_Chan_2] [Kin_Chan_2]
dtn-bundle 4556 dccp DTN Bundle DCCP CL Protocol 2013-11-12 2014-02-21 [RFC7122] 1685351985
dsx-monitor 31685 tcp DS Expert Monitor

IANA assigned this well-formed service name as a replacement for "dsx_monitor".
[John_Lowery] [John_Lowery] 2008-08-21
dsx_monitor 31685 tcp DS Expert Monitor [John_Lowery] [John_Lowery] 2008-08-21 This entry is an alias to "dsx-monitor". This entry is now historic, not usable for use with many common service discovery mechanisms.
31685 udp Reserved

Contact Information

ID Name Organization Contact URI Last Updated
[John_Lowery] John Lowery NetPro Computing mailto:jlowery&netpro.com 2008-08-21
[Kin_Chan_2] Kin Chan mailto:kchan&net2net.com