Service Name and Transport Protocol Port Number Registry

Last Updated
2026-09-02
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]

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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
xns-time 52 tcp XNS Time Protocol [Susie_Armstrong] [Susie_Armstrong]
xns-time 52 udp XNS Time Protocol [Susie_Armstrong] [Susie_Armstrong]
bftp 152 tcp Background File Transfer Program [Annette_DeSchon] [Annette_DeSchon]
bftp 152 udp Background File Transfer Program [Annette_DeSchon] [Annette_DeSchon]
dtag-ste-sb 352 tcp DTAG [Ruediger_Wald] [Ruediger_Wald] (assigned long ago)
dtag-ste-sb 352 udp DTAG [Ruediger_Wald] [Ruediger_Wald] (assigned long ago)
bhoedap4 352 tcp bhoedap4 [John_Kelly] [John_Kelly] This entry records an unassigned but widespread use (added 5/21/97)
bhoedap4 352 udp bhoedap4 [John_Kelly] [John_Kelly] This entry records an unassigned but widespread use (added 5/21/97)
sfs-config 452 tcp Cray SFS config server [Walter_Poxon] [Walter_Poxon]
sfs-config 452 udp Cray SFS config server [Walter_Poxon] [Walter_Poxon]
efs 520 tcp extended file name server
router 520 udp local routing process (on site); uses variant of Xerox NS routing information protocol - RIP
ripng 521 tcp ripng [Robert_E_Minnear] [Robert_E_Minnear]
ripng 521 udp ripng [Robert_E_Minnear] [Robert_E_Minnear]
ulp 522 tcp ULP [Max_Morris] [Max_Morris]
ulp 522 udp ULP [Max_Morris] [Max_Morris]
ibm-db2 523 tcp IBM-DB2 [Juliana_Hsu] [Juliana_Hsu]
ibm-db2 523 udp IBM-DB2 [Juliana_Hsu] [Juliana_Hsu]
ncp 524 tcp NCP [Don_Provan_2] [Don_Provan_2]
ncp 524 udp NCP [Don_Provan_2] [Don_Provan_2]
timed 525 tcp timeserver
timed 525 udp timeserver
tempo 526 tcp newdate
tempo 526 udp newdate
stx 527 tcp Stock IXChange [Ferdi_Ladeira] [Ferdi_Ladeira] 2022-01-25
stx 527 udp Stock IXChange [Ferdi_Ladeira] [Ferdi_Ladeira] 2022-01-25
custix 528 tcp Customer IXChange [Ferdi_Ladeira] [Ferdi_Ladeira] 2022-01-25
custix 528 udp Customer IXChange [Ferdi_Ladeira] [Ferdi_Ladeira] 2022-01-25
irc-serv 529 tcp IRC-SERV [Brian_Tackett] [Brian_Tackett]
irc-serv 529 udp IRC-SERV [Brian_Tackett] [Brian_Tackett]
devshr-nts 552 tcp DeviceShare [Benjamin_Rosenberg] [Benjamin_Rosenberg]
devshr-nts 552 udp DeviceShare [Benjamin_Rosenberg] [Benjamin_Rosenberg]
xmlrpc-beep 602 tcp XML-RPC over BEEP [RFC3529]
xmlrpc-beep 602 udp XML-RPC over BEEP [RFC3529]
hello-port 652 tcp HELLO_PORT [Patrick_Cipiere] [Patrick_Cipiere]
hello-port 652 udp HELLO_PORT [Patrick_Cipiere] [Patrick_Cipiere]
qrh 752 tcp
qrh 752 udp
849-852 Unassigned
916-952 Unassigned
ddt 1052 tcp Dynamic DNS Tools [Remi_Lefebvre] [Remi_Lefebvre]
ddt 1052 udp Dynamic DNS Tools [Remi_Lefebvre] [Remi_Lefebvre]
winpoplanmess 1152 tcp Winpopup LAN Messenger [Vitali_Fomine] [Vitali_Fomine] 2005-11
winpoplanmess 1152 udp Winpopup LAN Messenger [Vitali_Fomine] [Vitali_Fomine] 2005-11
bspne-pcc 1252 tcp bspne-pcc
bspne-pcc 1252 udp bspne-pcc
lotusnote 1352 tcp Lotus Note [Greg_Pflaum] [Greg_Pflaum] 1992-07
lotusnote 1352 udp Lotus Note [Greg_Pflaum] [Greg_Pflaum] 1992-07
gtegsc-lm 1452 tcp GTE Government Systems License Man [Mike_Gregory] [Mike_Gregory]
gtegsc-lm 1452 udp GTE Government Systems License Man [Mike_Gregory] [Mike_Gregory]
atm-zip-office 1520 tcp atm zip office [Wilson_Kwan] [Wilson_Kwan]
atm-zip-office 1520 udp atm zip office [Wilson_Kwan] [Wilson_Kwan]
ncube-lm 1521 tcp nCube License Manager [Maxine_Yuen] [Maxine_Yuen] 2022-02-14 Unauthorized Use Known on port 1521
ncube-lm 1521 udp nCube License Manager [Maxine_Yuen] [Maxine_Yuen] 2022-02-14 Unauthorized Use Known on port 1521
ricardo-lm 1522 tcp Ricardo North America License Manager [Mike_Flemming] [Mike_Flemming]
ricardo-lm 1522 udp Ricardo North America License Manager [Mike_Flemming] [Mike_Flemming]
cichild-lm 1523 tcp cichild [Andy_Burgess] [Andy_Burgess]
cichild-lm 1523 udp cichild [Andy_Burgess] [Andy_Burgess]
ingreslock 1524 tcp ingres
ingreslock 1524 udp ingres
orasrv 1525 tcp oracle
orasrv 1525 udp oracle
prospero-np 1525 tcp Prospero Directory Service non-priv
prospero-np 1525 udp Prospero Directory Service non-priv
pdap-np 1526 tcp Prospero Data Access Prot non-priv [B_Clifford_Neuman] [B_Clifford_Neuman]
pdap-np 1526 udp Prospero Data Access Prot non-priv [B_Clifford_Neuman] [B_Clifford_Neuman]
tlisrv 1527 tcp oracle
tlisrv 1527 udp oracle
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
coauthor 1529 tcp oracle
coauthor 1529 udp oracle
pciarray 1552 tcp pciarray [Ron_Folk] [Ron_Folk]
pciarray 1552 udp pciarray [Ron_Folk] [Ron_Folk]
xnmp 1652 tcp xnmp [Ali_Saleh] [Ali_Saleh]
xnmp 1652 udp xnmp [Ali_Saleh] [Ali_Saleh]
lofr-lm 1752 tcp Leap of Faith Research License Manager
lofr-lm 1752 udp Leap of Faith Research License Manager
virtual-time 1852 tcp Virtual Time [Angie_S_Morner] [Angie_S_Morner]
virtual-time 1852 udp Virtual Time [Angie_S_Morner] [Angie_S_Morner]
mpnjsc 1952 tcp mpnjsc [Takenori_Miyahara] [Takenori_Miyahara]
mpnjsc 1952 udp mpnjsc [Takenori_Miyahara] [Takenori_Miyahara]
clearvisn 2052 tcp clearVisn Services Port [Dave_Lyons] [Dave_Lyons]
clearvisn 2052 udp clearVisn Services Port [Dave_Lyons] [Dave_Lyons]
gtp-user 2152 tcp GTP-User Plane (3GPP) [Alessio_Casati] [Alessio_Casati]
gtp-user 2152 udp GTP-User Plane (3GPP) [Alessio_Casati] [Alessio_Casati]
njenet-ssl 2252 tcp NJENET using SSL [Hans_U_Schmidt] [Hans_U_Schmidt]
njenet-ssl 2252 udp NJENET using SSL [Hans_U_Schmidt] [Hans_U_Schmidt]
pslserver 2352 tcp pslserver
pslserver 2352 udp pslserver
snifferclient 2452 tcp SnifferClient [Amy_Weaver_2] [Amy_Weaver_2]
snifferclient 2452 udp SnifferClient [Amy_Weaver_2] [Amy_Weaver_2]
pvsw 2520 tcp Pervasive Listener [Chuck_Talk] [Chuck_Talk]
pvsw 2520 udp Pervasive Listener [Chuck_Talk] [Chuck_Talk]
adaptecmgr 2521 tcp Adaptec Manager [Mark_Parenti] [Mark_Parenti]
adaptecmgr 2521 udp Adaptec Manager [Mark_Parenti] [Mark_Parenti]
windb 2522 tcp WinDb [Larry_Traylor] [Larry_Traylor]
windb 2522 udp WinDb [Larry_Traylor] [Larry_Traylor]
qke-llc-v3 2523 tcp Qke LLC V.3 [Joerg_Niehoff] [Joerg_Niehoff]

Contact Information

ID Name Organization Contact URI Last Updated
[Alessio_Casati] Alessio Casati mailto:a.casati&computer.org
[Ali_Saleh] Ali Saleh mailto:scomm&cerf.net
[Amy_Weaver_2] Amy Weaver mailto:amy_weaver&nai.com
[Andy_Burgess] Andy Burgess mailto:aab&cichlid.com
[Angie_S_Morner] Angie S. Morner mailto:webmaster&dsbcpas.com
[Annette_DeSchon] Annette DeSchon mailto:DESCHON&isi.edu
[B_Clifford_Neuman] B. Clifford Neuman mailto:bcn&isi.edu 2022-02-18
[Benjamin_Rosenberg] Benjamin Rosenberg mailto:brosenberg&advsyscon.com
[Brian_Tackett] Brian Tackett mailto:cym&acrux.net
[Chuck_Talk] Chuck Talk mailto:ctalk&pervasive.com
[Dave_Lyons] Dave Lyons mailto:dlyons&dnpg.com
[Don_Provan_2] Don Provan mailto:donp&sjf.novell.com
[Ferdi_Ladeira] Ferdi Ladeira mailto:f.lad.mail&gmail.com 2022-01-25
[Greg_Pflaum] Greg Pflaum mailto:iris.com!Greg_Pflaum&uunet.uu.net 1992-07
[Hans_U_Schmidt] Hans U Schmidt mailto:schmidth&de.ibm.com
[Joerg_Niehoff] Joerg Niehoff mailto:joerg.niehoff&alcatel-ke.de
[John_Kelly] John Kelly mailto:johnk&bellhow.com
[Juliana_Hsu] Juliana Hsu mailto:jhsu&ca.ibm.com
[Larry_Traylor] Larry Traylor mailto:larry&arium.com
[Mark_Parenti] Mark Parenti mailto:map&ntc.adaptec.com
[Max_Morris] Max Morris mailto:maxm&microsoft.com
[Maxine_Yuen] Maxine Yuen mailto:maxine&hq.ncube.com
[Mike_Flemming] Mike Flemming mailto:mf&xnet.com
[Mike_Gregory] Mike Gregory mailto:Gregory_Mike&msmail.iipo.gtegsc.com
[Mikael_Voss] Mikael Voss mailto:mvs&nyantec.com 2017-04-18
[nyantec] nyantec mailto:info&nyantec.com 2017-04-18
[Patrick_Cipiere] Patrick Cipiere mailto:Patrick.Cipiere&udcast.com
[Remi_Lefebvre] Remi Lefebvre mailto:remi&debian.org
[Robert_E_Minnear] Robert E. Minnear mailto:minnear&ipsilon.com
[Ron_Folk] Ron Folk mailto:rfolkes&avl.com
[Ruediger_Wald] Ruediger Wald mailto:wald&ez-darmstadt.telekom.de
[Susie_Armstrong] Susie Armstrong mailto:Armstrong.wbst128@xerox
[Takenori_Miyahara] Takenori Miyahara mailto:miyahara&pfu.co.jp
[Vitali_Fomine] Vitali Fomine mailto:info&winpopup-lan-messenger.com 2005-11
[Walter_Poxon] Walter Poxon mailto:wdp&ironwood.cray.com
[Wilson_Kwan] Wilson Kwan mailto:wilsonk%25toronto@zip.atm.com