Service Name and Transport Protocol Port Number Registry
Last Updated
- 2026-10-15
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
- RFC 6335: Internet Assigned Numbers Authority (IANA) Procedures for the Management of the Service Name and Transport Protocol Port Number Registry
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 basis, as described in RFC 6335.
Port numbers are divided into three ranges, with their uses and assignment procedures specified in Section 8.1.2 of RFC 6335:
- System Ports (0-1023) are assigned using the IETF Review or IESG Approval procedures.
- User Ports (1024-49151) are assigned using the IETF Review, IESG Approval, or Expert Review procedures.
- Dynamic and/or Private Ports (49152-65535) are not assigned.
The registration procedures for service names and port numbers are specified in RFC 6335, while the registration policies referenced above are defined in RFC 8126.
Assigned ports both System and User ports SHOULD NOT be used without or prior to IANA registration.
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.
Registration Forms
- To request a new assignment, please use the Application for Service Names and User Port Numbers form.
- To modify an existing assignment, please use the Modify a Port Number Assignment form.
Available Formats
| Service Name | Port Number | Transport Protocol | Description | Assignee | Contact | Registration Date | Modification Date | Reference | Service Code | Unauthorized Use Reported | Assignment Notes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| discard | 9 | tcp | Discard | Jon Postel | Jon Postel | ||||||
| discard | 9 | udp | Discard | Jon Postel | Jon Postel | ||||||
| discard | 9 | sctp | Discard | Randall Stewart | Randall Stewart | 2022-02-07 | RFC 9260 | ||||
| discard | 9 | dccp | Discard | Eddie Kohler | Eddie Kohler | RFC 4340 | 1145656131 | ||||
| chargen | 19 | tcp | Character Generator | ||||||||
| chargen | 19 | udp | Character Generator | ||||||||
| ftp-data | 20 | sctp | FTP | Randall Stewart | Randall Stewart | 2022-02-07 | RFC 9260 | ||||
| ftp | 21 | tcp | File Transfer Protocol [Control] | Jon Postel | Jon Postel | RFC 959 | Defined TXT keys: u=<username> p=<password> path=<path> | ||||
| ftp | 21 | udp | File Transfer Protocol [Control] | Jon Postel | Jon Postel | RFC 959 | Defined TXT keys: u=<username> p=<password> path=<path> | ||||
| ftp | 21 | sctp | FTP | Randall Stewart | Randall Stewart | 2022-02-07 | RFC 9260 | Defined TXT keys: u=<username> p=<password> path=<path> | |||
| ssh | 22 | sctp | SSH | Randall Stewart | Randall Stewart | 2022-02-07 | RFC 9260 | Defined TXT keys: u=<username> p=<password> | |||
| msg-icp | 29 | tcp | MSG ICP | Robert Thomas | Robert Thomas | ||||||
| msg-icp | 29 | udp | MSG ICP | Robert Thomas | Robert Thomas | ||||||
| rlp | 39 | tcp | Resource Location Protocol | Mike Accetta | Mike Accetta | ||||||
| rlp | 39 | udp | Resource Location Protocol | Mike Accetta | Mike Accetta | ||||||
| tacacs | 49 | tcp | Login Host Protocol (TACACS) | Pieter Ditmars | Pieter Ditmars | ||||||
| tacacs | 49 | udp | Login Host Protocol (TACACS) | Pieter Ditmars | Pieter Ditmars | ||||||
| 59 | tcp | any private file service | Jon Postel | Jon Postel | |||||||
| 59 | udp | any private file service | Jon Postel | Jon Postel | |||||||
| bootps | 67 | tcp | Bootstrap Protocol Server | Bill Croft | Bill Croft | RFC 951 | Defined TXT keys: None | ||||
| tftp | 69 | tcp | Trivial File Transfer | David Clark | David Clark | ||||||
| tftp | 69 | udp | Trivial File Transfer | David Clark | David Clark | ||||||
| finger | 79 | tcp | Finger | David Zimmerman | David Zimmerman | Unauthorized use by some mail users (see [RFC4146] for details) | |||||
| finger | 79 | udp | Finger | David Zimmerman | David Zimmerman | Unauthorized use by some mail users (see [RFC4146] for details) | |||||
| http | 80 | tcp | World Wide Web HTTP | IESG | IETF Chair | 2021-10-01 | RFC 9110 | Defined TXT keys: u=<username> p=<password> path=<path to document> | |||
| http | 80 | udp | World Wide Web HTTP | IESG | IETF Chair | 2021-10-01 | RFC 9110 | Defined TXT keys: u=<username> p=<password> path=<path to document> | |||
| www | 80 | tcp | World Wide Web HTTP | IESG | IETF Chair | 2021-10-01 | RFC 9110 | This is a duplicate of the "http" service and should not be used for discovery purposes. | |||
| www | 80 | udp | World Wide Web HTTP | IESG | IETF Chair | 2021-10-01 | RFC 9110 | This is a duplicate of the "http" service and should not be used for discovery purposes. | |||
| http | 80 | sctp | HTTP | Randall Stewart | Randall Stewart | 2022-02-07 | RFC 9260 | Defined TXT keys: u=<username> p=<password> path=<path to document> | |||
| su-mit-tg | 89 | tcp | SU/MIT Telnet Gateway | Mark Crispin | Mark Crispin | ||||||
| su-mit-tg | 89 | udp | SU/MIT Telnet Gateway | Mark Crispin | Mark Crispin | ||||||
| dnsix | 90 | tcp | DNSIX Securit Attribute Token Map | Charles Watt | Charles Watt | PORT 90 also being used unofficially by Pointcast | |||||
| dnsix | 90 | udp | DNSIX Securit Attribute Token Map | Charles Watt | Charles Watt | PORT 90 also being used unofficially by Pointcast | |||||
| mit-dov | 91 | tcp | MIT Dover Spooler | Eliot Moss | Eliot Moss | ||||||
| mit-dov | 91 | udp | MIT Dover Spooler | Eliot Moss | Eliot Moss | ||||||
| npp | 92 | tcp | Network Printing Protocol | Louis Mamakos | Louis Mamakos | ||||||
| npp | 92 | udp | Network Printing Protocol | Louis Mamakos | Louis Mamakos | ||||||
| dcp | 93 | tcp | Device Control Protocol | Daniel Tappan | Daniel Tappan | ||||||
| dcp | 93 | udp | Device Control Protocol | Daniel Tappan | Daniel Tappan | ||||||
| objcall | 94 | tcp | Tivoli Object Dispatcher | Tom Bereiter | Tom Bereiter | ||||||
| objcall | 94 | udp | Tivoli Object Dispatcher | Tom Bereiter | Tom Bereiter | ||||||
| supdup | 95 | tcp | SUPDUP | Mark Crispin | Mark Crispin | ||||||
| supdup | 95 | udp | SUPDUP | Mark Crispin | Mark Crispin | ||||||
| dixie | 96 | tcp | DIXIE Protocol Specification | Tim Howes | Tim Howes | ||||||
| dixie | 96 | udp | DIXIE Protocol Specification | Tim Howes | Tim Howes | ||||||
| swift-rvf | 97 | tcp | Swift Remote Virtural File Protocol | Maurice R. Turcotte | Maurice R. Turcotte | ||||||
| swift-rvf | 97 | udp | Swift Remote Virtural File Protocol | Maurice R. Turcotte | Maurice R. Turcotte | ||||||
| tacnews | 98 | tcp | TAC News | Jon Postel | Jon Postel | ||||||
| tacnews | 98 | udp | TAC News | Jon Postel | Jon Postel | ||||||
| metagram | 99 | tcp | Metagram Relay | Geoff Goodfellow | Geoff Goodfellow | ||||||
| metagram | 99 | udp | Metagram Relay | Geoff Goodfellow | Geoff Goodfellow | ||||||
| pop2 | 109 | tcp | Post Office Protocol - Version 2 | Joyce K. Reynolds | Joyce K. Reynolds | ||||||
| pop2 | 109 | udp | Post Office Protocol - Version 2 | Joyce K. Reynolds | Joyce K. Reynolds | ||||||
| nntp | 119 | tcp | Network News Transfer Protocol | IESG | IETF Chair | 2018-07-06 | RFC 3977 | ||||
| nntp | 119 | udp | Network News Transfer Protocol | IESG | IETF Chair | 2018-07-06 | RFC 3977 | ||||
| ntp | 123 | tcp | Network Time Protocol | Dave Mills | Dave Mills | RFC 5905 | |||||
| ntp | 123 | udp | Network Time Protocol | Dave Mills | Dave Mills | RFC 5905 | |||||
| pwdgen | 129 | tcp | Password Generator Protocol | Frank J. Wacho | Frank J. Wacho | ||||||
| pwdgen | 129 | udp | Password Generator Protocol | Frank J. Wacho | Frank J. Wacho | ||||||
| netbios-ssn | 139 | tcp | NETBIOS Session Service | Jon Postel | Jon Postel | ||||||
| netbios-ssn | 139 | udp | NETBIOS Session Service | Jon Postel | Jon Postel | ||||||
| imap | 143 | tcp | Internet Message Access Protocol | IESG | IETF Chair | 2021-02-22 | RFC 3501; RFC 9051 | ||||
| 143 | udp | Reserved | 2021-02-22 | RFC 9051 | |||||||
| aed-512 | 149 | tcp | AED 512 Emulation Service | Albert G. Broscius | Albert G. Broscius | ||||||
| aed-512 | 149 | udp | AED 512 Emulation Service | Albert G. Broscius | Albert G. Broscius | ||||||
| nss-routing | 159 | tcp | NSS-Routing | Yakov Rekhter | Yakov Rekhter | ||||||
| nss-routing | 159 | udp | NSS-Routing | Yakov Rekhter | Yakov Rekhter | ||||||
| send | 169 | tcp | SEND | William Oldwin | William Oldwin | 2019-04-22 | |||||
| send | 169 | udp | SEND | William Oldwin | William Oldwin | 2019-04-22 | |||||
| bgp | 179 | tcp | Border Gateway Protocol | Kirk Lougheed | Kirk Lougheed | ||||||
| bgp | 179 | udp | Border Gateway Protocol | Kirk Lougheed | Kirk Lougheed | ||||||
| bgp | 179 | sctp | BGP | Randall Stewart | Randall Stewart | 2022-02-07 | RFC 9260 | ||||
| qft | 189 | tcp | Queued File Transport | Wayne Schroeder | Wayne Schroeder | ||||||
| qft | 189 | udp | Queued File Transport | Wayne Schroeder | Wayne Schroeder | ||||||
| gacp | 190 | tcp | Gateway Access Control Protocol | C. Philip Wood | C. Philip Wood | ||||||
| gacp | 190 | udp | Gateway Access Control Protocol | C. Philip Wood | C. Philip Wood | ||||||
| prospero | 191 | tcp | Prospero Directory Service | B. Clifford Neuman | B. Clifford Neuman | ||||||
| prospero | 191 | udp | Prospero Directory Service | B. Clifford Neuman | B. Clifford Neuman | ||||||
| osu-nms | 192 | tcp | OSU Network Monitoring System | Doug Karl | Doug Karl | ||||||
| osu-nms | 192 | udp | OSU Network Monitoring System | Doug Karl | Doug Karl | ||||||
| srmp | 193 | tcp | Spider Remote Monitoring Protocol | Ted J. Socolofsky | Ted J. Socolofsky | ||||||
| srmp | 193 | udp | Spider Remote Monitoring Protocol | Ted J. Socolofsky | Ted J. Socolofsky | ||||||
| irc | 194 | tcp | Internet Relay Chat Protocol | Jarkko Oikarinen | Jarkko Oikarinen | ||||||
| irc | 194 | udp | Internet Relay Chat Protocol | Jarkko Oikarinen | Jarkko Oikarinen | ||||||
| dn6-nlm-aud | 195 | tcp | DNSIX Network Level Module Audit | ||||||||
| dn6-nlm-aud | 195 | udp | DNSIX Network Level Module Audit | ||||||||
| dn6-smm-red | 196 | tcp | DNSIX Session Mgt Module Audit Redir | Lawrence Lebahn | Lawrence Lebahn | ||||||
| dn6-smm-red | 196 | udp | DNSIX Session Mgt Module Audit Redir | Lawrence Lebahn | Lawrence Lebahn | ||||||
| dls | 197 | tcp | Directory Location Service | ||||||||
| dls | 197 | udp | Directory Location Service | ||||||||
| dls-mon | 198 | tcp | Directory Location Service Monitor | Scott Bellew | Scott Bellew | ||||||
| dls-mon | 198 | udp | Directory Location Service Monitor | Scott Bellew | Scott Bellew | ||||||
| smux | 199 | tcp | SMUX | Marshall Rose | Marshall Rose | ||||||
| smux | 199 | udp | SMUX | Marshall Rose | Marshall Rose | ||||||
| qmtp | 209 | tcp | The Quick Mail Transfer Protocol | D. J. Bernstein | D. J. Bernstein | 2018-04-05 | |||||
| qmtp | 209 | udp | The Quick Mail Transfer Protocol | D. J. Bernstein | D. J. Bernstein | 2018-04-05 | |||||
| z39-50 | 210 | tcp | ANSI Z39.50 IANA assigned this well-formed service name as a replacement for "z39.50". |
Mark H. Needleman | Mark H. Needleman | ||||||
| z39.50 | 210 | tcp | ANSI Z39.50 | Mark H. Needleman | Mark H. Needleman | This entry is an alias to "z39-50". This entry is now historic, not usable for use with many common service discovery mechanisms. | |||||
| z39-50 | 210 | udp | ANSI Z39.50 IANA assigned this well-formed service name as a replacement for "z39.50". |
Mark H. Needleman | Mark H. Needleman | ||||||
| z39.50 | 210 | udp | ANSI Z39.50 | Mark H. Needleman | Mark H. Needleman | This entry is an alias to "z39-50". This entry is now historic, not usable for use with many common service discovery mechanisms. |