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
set 257 tcp Secure Electronic Transaction [Donald_Eastlake] [Donald_Eastlake]
set 257 udp Secure Electronic Transaction [Donald_Eastlake] [Donald_Eastlake]
shockwave2 1257 tcp Shockwave 2 [Dave_Simmons] [Dave_Simmons]
shockwave2 1257 udp Shockwave 2 [Dave_Simmons] [Dave_Simmons]
simple-tx-rx 2257 tcp simple text/file transfer [Daniel_Kilsdonk] [Daniel_Kilsdonk] 2006-08
simple-tx-rx 2257 udp simple text/file transfer [Daniel_Kilsdonk] [Daniel_Kilsdonk] 2006-08
hs-port 2570 tcp HS Port [Uri_Doron] [Uri_Doron]
hs-port 2570 udp HS Port [Uri_Doron] [Uri_Doron]
cecsvc 2571 tcp CECSVC [Roger_Pao] [Roger_Pao]
cecsvc 2571 udp CECSVC [Roger_Pao] [Roger_Pao]
ibp 2572 tcp IBP [Jonathan_Downes] [Jonathan_Downes]
ibp 2572 udp IBP [Jonathan_Downes] [Jonathan_Downes]
trustestablish 2573 tcp Trust Establish [Yosi_Mass] [Yosi_Mass]
trustestablish 2573 udp Trust Establish [Yosi_Mass] [Yosi_Mass]
blockade-bpsp 2574 tcp Blockade BPSP [Blockade] [Blockade]
blockade-bpsp 2574 udp Blockade BPSP [Blockade] [Blockade]
hl7 2575 tcp HL7 [Tim_Jacobs] [Tim_Jacobs]
hl7 2575 udp HL7 [Tim_Jacobs] [Tim_Jacobs]
tclprodebugger 2576 tcp TCL Pro Debugger
tclprodebugger 2576 udp TCL Pro Debugger
scipticslsrvr 2577 tcp Scriptics Lsrvr [Brent_Welch] [Brent_Welch]
scipticslsrvr 2577 udp Scriptics Lsrvr [Brent_Welch] [Brent_Welch]
rvs-isdn-dcp 2578 tcp RVS ISDN DCP [Michael_Zirpel] [Michael_Zirpel]
rvs-isdn-dcp 2578 udp RVS ISDN DCP [Michael_Zirpel] [Michael_Zirpel]
mpfoncl 2579 tcp mpfoncl [Itaru_Kimura] [Itaru_Kimura]
mpfoncl 2579 udp mpfoncl [Itaru_Kimura] [Itaru_Kimura]
cpqrpm-server 3257 tcp Compaq RPM Server Port [Royal_King] [Royal_King] 2002-02
cpqrpm-server 3257 udp Compaq RPM Server Port [Royal_King] [Royal_King] 2002-02
25605-25792 Unassigned
vocaltec-hos 25793 tcp Vocaltec Address Server [Scott_Petrack] [Scott_Petrack]
vocaltec-hos 25793 udp Vocaltec Address Server [Scott_Petrack] [Scott_Petrack]
25794-25899 Unassigned
cockroach 26257 tcp CockroachDB [Cockroach_Labs_Inc] [Ben_Darnell] 2015-09-29
26257 udp Reserved

Contact Information

ID Name Organization Contact URI Last Updated
[Ben_Darnell] mailto:ben&cockroachlabs.com 2015-09-29
[Blockade] VP - Research & Development mailto:development&blockade.com
[Brent_Welch] Brent Welch mailto:welch&scriptics.com
[Cockroach_Labs_Inc] Cockroach Labs, Inc. mailto:iana-contact&cockroachlabs.com 2015-09-29
[Daniel_Kilsdonk] Daniel Kilsdonk mailto:dan&prospeed.net 2006-08
[Dave_Simmons] Dave Simmons mailto:dsimmons&macromedia.com
[Donald_Eastlake] Donald Eastlake mailto:d3e3e3&gmail.com
[Itaru_Kimura] Itaru Kimura mailto:kimura&kel.fujitsu.co.jp
[Jonathan_Downes] Jonathan Downes mailto:jonno&activ.net.au
[Michael_Zirpel] Michael Zirpel mailto:mbz&rvscom.com
[Roger_Pao] Roger Pao mailto:rpao&corder-eng.com
[Royal_King] Royal King mailto:royal.king&compaq.com 2002-02
[Scott_Petrack] Scott Petrack mailto:Scott_Petrack&vocaltec.com
[Tim_Jacobs] Tim Jacobs
[Uri_Doron] Uri Doron mailto:uri&il.netect.com
[Yosi_Mass] Yosi Mass mailto:yosimass&haifa.vnet.ibm.com