Internet Assigned Numbers Authority

Service Name and Transport Protocol Port Number Registry

Last Updated
2025-08-26
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]

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Service Name Port Number Transport Protocol Description Assignee Contact Registration Date Modification Date Reference Service Code Unauthorized Use Reported Assignment Notes
isi-gl 55 tcp ISI Graphics Language
isi-gl 55 udp ISI Graphics Language
netsc-dev 155 tcp NETSC [Sergio_Heker] [Sergio_Heker]
netsc-dev 155 udp NETSC [Sergio_Heker] [Sergio_Heker]
249-255 Reserved 2024-12-20 [RFC1060]
datex-asn 355 tcp DATEX-ASN [Kenneth_Vaughn] [Kenneth_Vaughn]
datex-asn 355 udp DATEX-ASN [Kenneth_Vaughn] [Kenneth_Vaughn]
creativepartnr 455 tcp CreativePartnr [Jesus_Ortiz] [Jesus_Ortiz]
creativepartnr 455 udp CreativePartnr [Jesus_Ortiz] [Jesus_Ortiz]
new-rwho 550 tcp new-who [n/a]
new-rwho 550 udp new-who [n/a]
cybercash 551 tcp cybercash [Donald_E_Eastlake] [Donald_E_Eastlake] [RFC1898]
cybercash 551 udp cybercash [Donald_E_Eastlake] [Donald_E_Eastlake] [RFC1898]
devshr-nts 552 tcp DeviceShare [Benjamin_Rosenberg] [Benjamin_Rosenberg]
devshr-nts 552 udp DeviceShare [Benjamin_Rosenberg] [Benjamin_Rosenberg]
pirp 553 tcp pirp [D_J_Bernstein] [D_J_Bernstein]
pirp 553 udp pirp [D_J_Bernstein] [D_J_Bernstein]
rtsp 554 tcp Real Time Streaming Protocol (RTSP) [Rob_Lanphier] [Rob_Lanphier]
rtsp 554 udp Real Time Streaming Protocol (RTSP) [Rob_Lanphier] [Rob_Lanphier]
dsf 555 tcp
dsf 555 udp
remotefs 556 tcp rfs server
remotefs 556 udp rfs server
openvms-sysipc 557 tcp openvms-sysipc [Alan_Potter] [Alan_Potter]
openvms-sysipc 557 udp openvms-sysipc [Alan_Potter] [Alan_Potter]
sdnskmp 558 tcp SDNSKMP
sdnskmp 558 udp SDNSKMP
teedtap 559 tcp TEEDTAP [Charlie_Limoges] [Charlie_Limoges]
teedtap 559 udp TEEDTAP [Charlie_Limoges] [Charlie_Limoges]
tinc 655 tcp TINC [Ivo_Timmermans] [Ivo_Timmermans]
tinc 655 udp TINC [Ivo_Timmermans] [Ivo_Timmermans]
755-757 Unassigned
855-859 Unassigned
ansyslmd 1055 tcp ANSYS - License Manager [Suzanne_Lorrin] [Suzanne_Lorrin]
ansyslmd 1055 udp ANSYS - License Manager [Suzanne_Lorrin] [Suzanne_Lorrin]
nfa 1155 tcp Network File Access [James_Powell] [James_Powell]
nfa 1155 udp Network File Access [James_Powell] [James_Powell]
q55-pcc 1253 tcp q55-pcc [Prem_Tirilok] [Prem_Tirilok]
q55-pcc 1253 udp q55-pcc [Prem_Tirilok] [Prem_Tirilok]
de-cache-query 1255 tcp de-cache-query
de-cache-query 1255 udp de-cache-query
intuitive-edge 1355 tcp Intuitive Edge [Montgomery_Zukowski] [Montgomery_Zukowski]
intuitive-edge 1355 udp Intuitive Edge [Montgomery_Zukowski] [Montgomery_Zukowski]
esl-lm 1455 tcp ESL License Manager [Abel_Chou] [Abel_Chou]
esl-lm 1455 udp ESL License Manager [Abel_Chou] [Abel_Chou]
3m-image-lm 1550 tcp Image Storage license manager 3M Company [J_C_Canessa] [J_C_Canessa]
3m-image-lm 1550 udp Image Storage license manager 3M Company [J_C_Canessa] [J_C_Canessa]
hecmtl-db 1551 tcp HECMTL-DB [Maxime_Belanger] [Maxime_Belanger]
hecmtl-db 1551 udp HECMTL-DB [Maxime_Belanger] [Maxime_Belanger]
pciarray 1552 tcp pciarray [Ron_Folk] [Ron_Folk]
pciarray 1552 udp pciarray [Ron_Folk] [Ron_Folk]
sna-cs 1553 tcp sna-cs [Tony_Sowter] [Tony_Sowter]
sna-cs 1553 udp sna-cs [Tony_Sowter] [Tony_Sowter]
caci-lm 1554 tcp CACI Products Company License Manager [Erik_Blume] [Erik_Blume]
caci-lm 1554 udp CACI Products Company License Manager [Erik_Blume] [Erik_Blume]
livelan 1555 tcp livelan [Kaynam_Hedayat] [Kaynam_Hedayat]
livelan 1555 udp livelan [Kaynam_Hedayat] [Kaynam_Hedayat]
veritas-pbx 1556 tcp VERITAS Private Branch Exchange

IANA assigned this well-formed service name as a replacement for "veritas_pbx".
[Stefan_Winkel] [Stefan_Winkel] 2004-04
veritas_pbx 1556 tcp VERITAS Private Branch Exchange [Stefan_Winkel] [Stefan_Winkel] 2004-04 This entry is an alias to "veritas-pbx". This entry is now historic, not usable for use with many common service discovery mechanisms.
veritas-pbx 1556 udp VERITAS Private Branch Exchange

IANA assigned this well-formed service name as a replacement for "veritas_pbx".
[Stefan_Winkel] [Stefan_Winkel] 2004-04
veritas_pbx 1556 udp VERITAS Private Branch Exchange [Stefan_Winkel] [Stefan_Winkel] 2004-04 This entry is an alias to "veritas-pbx". This entry is now historic, not usable for use with many common service discovery mechanisms.
arbortext-lm 1557 tcp ArborText License Manager [David_J_Wilson] [David_J_Wilson]
arbortext-lm 1557 udp ArborText License Manager [David_J_Wilson] [David_J_Wilson]
xingmpeg 1558 tcp xingmpeg [Howard_Gordon] [Howard_Gordon]
xingmpeg 1558 udp xingmpeg [Howard_Gordon] [Howard_Gordon]
web2host 1559 tcp web2host [Stephen_Johnson] [Stephen_Johnson]
web2host 1559 udp web2host [Stephen_Johnson] [Stephen_Johnson]
dec-mbadmin 1655 tcp dec-mbadmin
dec-mbadmin 1655 udp dec-mbadmin
ms-streaming 1755 tcp ms-streaming [Bret_O_Rourke] [Bret_O_Rourke]
ms-streaming 1755 udp ms-streaming [Bret_O_Rourke] [Bret_O_Rourke]
fiorano-rtrsvc 1855 tcp Fiorano RtrSvc
fiorano-rtrsvc 1855 udp Fiorano RtrSvc
abr-secure 1955 tcp ABR-Secure Data (diskbridge) [Graham_Wooden] [Graham_Wooden]
abr-secure 1955 udp ABR-Secure Data (diskbridge) [Graham_Wooden] [Graham_Wooden]
iop 2055 tcp Iliad-Odyssey Protocol [Bruce_Lueckenhoff] [Bruce_Lueckenhoff]
iop 2055 udp Iliad-Odyssey Protocol [Bruce_Lueckenhoff] [Bruce_Lueckenhoff]
brdptc 2155 tcp Bridge Protocol [Hideki_Hatta] [Hideki_Hatta] 2007-09-27
brdptc 2155 udp Bridge Protocol [Hideki_Hatta] [Hideki_Hatta] 2007-09-27
vrtp 2255 tcp VRTP - ViRtue Transfer Protocol [Max_Fudim] [Max_Fudim]
vrtp 2255 udp VRTP - ViRtue Transfer Protocol [Max_Fudim] [Max_Fudim]
psdbserver 2355 tcp psdbserver [Paul_Reddy] [Paul_Reddy]
psdbserver 2355 udp psdbserver [Paul_Reddy] [Paul_Reddy]
wago-io-system 2455 tcp WAGO-IO-SYSTEM [Jorg_Hoffmann] [Jorg_Hoffmann]
wago-io-system 2455 udp WAGO-IO-SYSTEM [Jorg_Hoffmann] [Jorg_Hoffmann]
ads 2550 tcp ADS [Michael_O_Connor] [Michael_O_Connor]
ads 2550 udp ADS [Michael_O_Connor] [Michael_O_Connor]
isg-uda-server 2551 tcp ISG UDA Server [Dror_Harari] [Dror_Harari]
isg-uda-server 2551 udp ISG UDA Server [Dror_Harari] [Dror_Harari]
call-logging 2552 tcp Call Logging [Dean_Webb] [Dean_Webb]
call-logging 2552 udp Call Logging [Dean_Webb] [Dean_Webb]
efidiningport 2553 tcp efidiningport [Lynn_Carter] [Lynn_Carter]
efidiningport 2553 udp efidiningport [Lynn_Carter] [Lynn_Carter]
vcnet-link-v10 2554 tcp VCnet-Link v10 [Csaba_Mate] [Csaba_Mate]
vcnet-link-v10 2554 udp VCnet-Link v10 [Csaba_Mate] [Csaba_Mate]
compaq-wcp 2555 tcp Compaq WCP [Ferruccio_Barletta] [Ferruccio_Barletta]
compaq-wcp 2555 udp Compaq WCP [Ferruccio_Barletta] [Ferruccio_Barletta]
nicetec-nmsvc 2556 tcp nicetec-nmsvc
nicetec-nmsvc 2556 udp nicetec-nmsvc
nicetec-mgmt 2557 tcp nicetec-mgmt [Joerg_Paulus] [Joerg_Paulus]

Contact Information

ID Name Contact URI Last Updated
[Abel_Chou] Abel Chou mailto:abel&willy.esl.com
[Alan_Potter] Alan Potter mailto:potter&movies.enet.dec.com
[Benjamin_Rosenberg] Benjamin Rosenberg mailto:brosenberg&advsyscon.com
[Bret_O_Rourke] Bret O'Rourke mailto:bretor&microsoft.com
[Bruce_Lueckenhoff] Bruce Lueckenhoff mailto:brucelu&cisco.com
[Charlie_Limoges] Charlie Limoges mailto:Charlie.Limoges&gdc4s.com
[Csaba_Mate] Csaba Mate mailto:mc36&freemail.c3.hu
[D_J_Bernstein] D. J. Bernstein mailto:ports&box.cr.yp.to 2018-04-05
[David_J_Wilson] David J. Wilson mailto:djw&arbortext.com
[Dean_Webb] Dean Webb mailto:dean.webb&ascend.com
[Donald_E_Eastlake] Donald E. Eastlake 3rd mailto:d3e3e3&gmail.com
[Dror_Harari] Dror Harari mailto:Dror.Harari&isgsoft.com
[Erik_Blume] Erik Blume mailto:erikb&caciasl.com
[Ferruccio_Barletta] Ferruccio Barletta mailto:ferruccio.barletta&compaq.com
[Graham_Wooden] Graham Wooden mailto:graham&g-rock.net
[Hideki_Hatta] Hideki Hatta mailto:ponum&canon-is.co.jp 2007-09-27
[Howard_Gordon] Howard Gordon mailto:hgordon&system.xingtech.com
[Ivo_Timmermans] Ivo Timmermans mailto:itimmermans&bigfoot.com
[J_C_Canessa] J. C. Canessa mailto:jccanessa&mmm.com
[James_Powell] James Powell mailto:james&mailhost.unidata.com
[Jesus_Ortiz] Jesus Ortiz mailto:jesus_ortiz&emotion.com
[Joerg_Paulus] Joerg Paulus mailto:tech&nicetec.de
[Jorg_Hoffmann] Jörg Hoffmann mailto:electronicc_rd&wago.com
[Kaynam_Hedayat] Kaynam Hedayat mailto:khedayat&roadrunner.pictel.com
[Kenneth_Vaughn] Kenneth Vaughn mailto:kvaughn&mail.viggen.com
[Lynn_Carter] Lynn Carter mailto:carterl&execpc.com
[Max_Fudim] Max Fudim mailto:fudim&virtue3d.com
[Maxime_Belanger] Maxime Belanger mailto:R173&hec.ca
[Michael_O_Connor] Michael O'Connor mailto:moconnor&adobe.com
[Montgomery_Zukowski] Montgomery Zukowski mailto:monty&nextnorth.acs.ohio-state.edu
[Paul_Reddy] Paul Reddy mailto:preddy&pharos.com
[Prem_Tirilok] Prem Tirilok mailto:Prem.Tirilok&tellabs.com
[Rob_Lanphier] Rob Lanphier mailto:robla&prognet.com
[Ron_Folk] Ron Folk mailto:rfolkes&avl.com
[Sergio_Heker] Sergio Heker mailto:heker&jvncc.csc.org
[Stefan_Winkel] Stefan Winkel mailto:stefan&veritas.com 2004-04
[Stephen_Johnson] Stephen Johnson mailto:sjohnson&mindspring.com
[Suzanne_Lorrin] Suzanne Lorrin mailto:suzanne.lorrin&ansys.com
[Tony_Sowter] Tony Sowter mailto:ts&datcon.co.uk