Internet Assigned Numbers Authority

Service Name and Transport Protocol Port Number Registry

Last Updated
2025-08-15
Expert(s)
TCP/UDP: Joe Touch; Eliot Lear, Kumiko Ono, Wes Eddy, Brian Trammell, 
Jana Iyengar, 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
smsd 596 udp SMSD [Wayne_Barlow] [Wayne_Barlow]
ptcnameservice 597 tcp PTC Name Service [Yuri_Machkasov] [Yuri_Machkasov]
ptcnameservice 597 udp PTC Name Service [Yuri_Machkasov] [Yuri_Machkasov]
sco-websrvrmg3 598 tcp SCO Web Server Manager 3 [Simon_Baldwin] [Simon_Baldwin]
sco-websrvrmg3 598 udp SCO Web Server Manager 3 [Simon_Baldwin] [Simon_Baldwin]
acp 599 tcp Aeolon Core Protocol [Michael_Alyn_Miller] [Michael_Alyn_Miller]
acp 599 udp Aeolon Core Protocol [Michael_Alyn_Miller] [Michael_Alyn_Miller]
syslog-conn 601 tcp Reliable Syslog Service [RFC3195]
syslog-conn 601 udp Reliable Syslog Service [RFC3195]
xmlrpc-beep 602 tcp XML-RPC over BEEP [RFC3529]
xmlrpc-beep 602 udp XML-RPC over BEEP [RFC3529]
soap-beep 605 tcp SOAP over BEEP [RFC4227]
soap-beep 605 udp SOAP over BEEP [RFC4227]
sco-inetmgr 615 tcp Internet Configuration Manager
sco-inetmgr 615 udp Internet Configuration Manager
dec-dlm 625 tcp DEC DLM

IANA assigned this well-formed service name as a replacement for "dec_dlm".
[Rudi_Martin_2] [Rudi_Martin_2]
dec_dlm 625 tcp DEC DLM [Rudi_Martin_2] [Rudi_Martin_2] This entry is an alias to "dec-dlm". This entry is now historic, not usable for use with many common service discovery mechanisms.
dec-dlm 625 udp DEC DLM

IANA assigned this well-formed service name as a replacement for "dec_dlm".
[Rudi_Martin_2] [Rudi_Martin_2]
dec_dlm 625 udp DEC DLM [Rudi_Martin_2] [Rudi_Martin_2] This entry is an alias to "dec-dlm". This entry is now historic, not usable for use with many common service discovery mechanisms.
rlzdbase 635 tcp RLZ DBase [Michael_Ginn] [Michael_Ginn]
rlzdbase 635 udp RLZ DBase [Michael_Ginn] [Michael_Ginn]
pssc 645 tcp PSSC [Egon_Meier_Engelen] [Egon_Meier_Engelen]
pssc 645 udp PSSC [Egon_Meier_Engelen] [Egon_Meier_Engelen]
dhcp-failover 647 tcp DHCP Failover [IESG] [IETF_Chair] 2018-05-21 [RFC8156]
obex 650 tcp OBEX [Jeff_Garbers] [Jeff_Garbers]
obex 650 udp OBEX [Jeff_Garbers] [Jeff_Garbers]
ieee-mms 651 tcp IEEE MMS [Curtis_Anderson] [Curtis_Anderson]
ieee-mms 651 udp IEEE MMS [Curtis_Anderson] [Curtis_Anderson]
hello-port 652 tcp HELLO_PORT [Patrick_Cipiere] [Patrick_Cipiere]
hello-port 652 udp HELLO_PORT [Patrick_Cipiere] [Patrick_Cipiere]
repscmd 653 tcp RepCmd [Scott_Dale_2] [Scott_Dale_2]
repscmd 653 udp RepCmd [Scott_Dale_2] [Scott_Dale_2]
aodv 654 tcp AODV [Charles_Perkins] [Charles_Perkins]
aodv 654 udp AODV [Charles_Perkins] [Charles_Perkins]
tinc 655 tcp TINC [Ivo_Timmermans] [Ivo_Timmermans]
tinc 655 udp TINC [Ivo_Timmermans] [Ivo_Timmermans]
spmp 656 tcp SPMP [Jakob_Kaivo] [Jakob_Kaivo]
spmp 656 udp SPMP [Jakob_Kaivo] [Jakob_Kaivo]
rmc 657 tcp RMC [Michael_Schmidt] [Michael_Schmidt]
rmc 657 udp RMC [Michael_Schmidt] [Michael_Schmidt]
tenfold 658 tcp TenFold [Louis_Olszyk] [Louis_Olszyk]
tenfold 658 udp TenFold [Louis_Olszyk] [Louis_Olszyk]
659 Removed 2001-06-06
sun-dr 665 tcp Sun DR [Harinder_Bhasin] [Harinder_Bhasin]
sun-dr 665 udp Sun DR [Harinder_Bhasin] [Harinder_Bhasin]
dctp 675 tcp DCTP [Andre_Kramer] [Andre_Kramer]
dctp 675 udp DCTP [Andre_Kramer] [Andre_Kramer]
mdc-portmapper 685 tcp MDC Port Mapper [Noah_Paul] [Noah_Paul]
mdc-portmapper 685 udp MDC Port Mapper [Noah_Paul] [Noah_Paul]
ieee-mms-ssl 695 tcp IEEE-MMS-SSL [Curtis_Anderson_2] [Curtis_Anderson_2]
ieee-mms-ssl 695 udp IEEE-MMS-SSL [Curtis_Anderson_2] [Curtis_Anderson_2]
epp 700 tcp Extensible Provisioning Protocol [RFC5734]
epp 700 udp Extensible Provisioning Protocol [RFC5734]
agentx 705 tcp AgentX [Bob_Natale] [Bob_Natale]
agentx 705 udp AgentX [Bob_Natale] [Bob_Natale]
iris-lwz 715 tcp IRIS-LWZ [RFC4993]
iris-lwz 715 udp IRIS-LWZ [RFC4993]
pana 716 udp PANA Messages [RFC5191]
745-746 Unassigned
rfile 750 tcp
loadav 750 udp
kerberos-iv 750 udp kerberos version iv [Martin_Hamilton] [Martin_Hamilton]
pump 751 tcp
pump 751 udp
qrh 752 tcp
qrh 752 udp
rrh 753 tcp
rrh 753 udp
tell 754 tcp send [Josyula_R_Rao] [Josyula_R_Rao]
tell 754 udp send [Josyula_R_Rao] [Josyula_R_Rao]
755-757 Unassigned
nlogin 758 tcp
nlogin 758 udp
con 759 tcp
con 759 udp
webster 765 tcp [Josyula_R_Rao] [Josyula_R_Rao]
webster 765 udp [Josyula_R_Rao] [Josyula_R_Rao]
entomb 775 tcp
acmaint-transd 775 udp

IANA assigned this well-formed service name as a replacement for "acmaint_transd".
acmaint_transd 775 udp This entry is an alias to "acmaint-transd". This entry is now historic, not usable for use with many common service discovery mechanisms.
781-785 Unassigned
gdoi 848 tcp GDOI [RFC3547]
gdoi 848 udp GDOI [RFC3547]
849-852 Unassigned
domain-s 853 tcp DNS query-response protocol run over TLS [IESG] [IETF_Chair] 2015-10-08 2022-04-11 [RFC7858]
domain-s 853 udp DNS query-response protocol run over DTLS or QUIC [IESG] [IETF_Chair] 2015-10-08 2022-04-01 [RFC7858][RFC8094][RFC9250]
dlep 854 tcp Dynamic Link Exchange Protocol (DLEP) [IESG] [IETF_Chair] 2017-04-03 [RFC8175]
dlep 854 udp Dynamic Link Exchange Protocol (DLEP) [IESG] [IETF_Chair] 2017-04-03 [RFC8175]
855-859 Unassigned
owamp-control 861 tcp OWAMP-Control [IESG] [IETF_Chair] [RFC4656]
owamp-test 861 udp OWAMP-Test [IESG] [IETF_Chair] 2018-12-21 [RFC8545]
twamp-control 862 tcp TWAMP-Control [IESG] [IETF_Chair] [RFC5357]
twamp-test 862 udp TWAMP-Test Receiver Port [IESG] [IETF_Chair] 2018-12-21 [RFC8545]
874-885 Unassigned
915 tcp Reserved
rift-ties 915 udp Routing in Fat Trees Topology Information Element [IESG] [IETF_Chair] 2023-02-17 2024-06-07 [RFC9692]
916-952 Unassigned
rndc 953 tcp BIND9 remote name daemon controller [Internet_Systems_Consortium_Inc] [Ray_Bellis] 2017-06-08
953 udp Reserved
954-988 Unassigned
imaps 993 tcp IMAP over TLS protocol [IESG] [IETF_Chair] 2021-02-22 [RFC3501][RFC8314][RFC9051]

Contact Information

ID Name Organization Contact URI Last Updated
[Andre_Kramer] Andre Kramer mailto:Andre.Kramer&ansa.co.uk
[Bob_Natale] Bob Natale mailto:bob.natale&appliedsnmp.com
[Charles_Perkins] Charles Perkins mailto:cperkins&eng.sun.com
[Curtis_Anderson] Curtis Anderson mailto:canderson&turbolinux.com
[Curtis_Anderson_2] Curtis Anderson mailto:ecanderson&turbolinux.com
[Egon_Meier_Engelen] Egon Meier-Engelen mailto:egon.meier-engelen&dlr.de
[Harinder_Bhasin] Harinder Bhasin mailto:Harinder.Bhasin&sun.com
[IESG] IESG mailto:iesg&ietf.org
[IETF_Chair] IETF Chair IETF mailto:chair&ietf.org
[Internet_Systems_Consortium_Inc] Internet Systems Consortium, Inc. mailto:info&isc.org 2017-06-08
[Ivo_Timmermans] Ivo Timmermans mailto:itimmermans&bigfoot.com
[Jakob_Kaivo] Jakob Kaivo mailto:jkaivo&nodomainname.net
[Jeff_Garbers] Jeff Garbers mailto:FJG030&email.mot.com
[Josyula_R_Rao] Josyula R. Rao mailto:jrrao&watson.ibm.com
[Louis_Olszyk] Louis Olszyk mailto:lolszyk&10fold.com
[Martin_Hamilton] Martin Hamilton mailto:martin&mrrl.lut.as.uk
[Michael_Alyn_Miller] Michael Alyn Miller mailto:iana&aeolon.com
[Michael_Ginn] Michael Ginn mailto:ginn&tyxar.com
[Michael_Schmidt] Michael Schmidt mailto:mmaass&us.ibm.com
[Noah_Paul] Noah Paul mailto:noahp&altavista.net
[Patrick_Cipiere] Patrick Cipiere mailto:Patrick.Cipiere&udcast.com
[Ray_Bellis] Ray Bellis mailto:ray&isc.org 2017-06-08
[Rudi_Martin_2] Rudi Martin mailto:Rudi.Martin&edo.mts.dec.com
[Scott_Dale_2] Scott Dale mailto:scott&tioga.com
[Simon_Baldwin] Simon Baldwin mailto:simonb&sco.com
[Wayne_Barlow] Wayne Barlow mailto:web&unx.dec.com
[Yuri_Machkasov] Yuri Machkasov mailto:yuri&ptc.com