Service Name and Transport Protocol Port Number Registry
- Last Updated
- 2026-10-09
- 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]
- 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 [RFC 6335]. 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 [RFC 6335]. According to Section 8.1.2 of [RFC 6335], System Ports are assigned by the "IETF Review" or "IESG Approval" procedures described in [RFC 8126]. User Ports are assigned by IANA using the "IETF Review" process, the "IESG Approval" process, or the "Expert Review" process, as per [RFC 6335]. Dynamic Ports are not assigned. The registration procedures for service names and port numbers are described in [RFC 6335]. 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
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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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 2 | tcp | Reserved | 2025-02-13 | De-assigned on 2025-02-13, previously compressnet by [Bernie_Volz] | |||||||
| 2 | udp | Reserved | 2025-02-13 | De-assigned on 2025-02-13, previously compressnet by [Bernie_Volz] | |||||||
| 3 | tcp | Reserved | 2025-02-13 | De-assigned on 2025-02-13, previously compressnet by [Bernie_Volz] | |||||||
| 3 | udp | Reserved | 2025-02-13 | De-assigned on 2025-02-13, previously compressnet by [Bernie_Volz] | |||||||
| ftp-data | 20 | tcp | File Transfer [Default Data] | [Jon_Postel] | [Jon_Postel] | ||||||
| ftp-data | 20 | udp | File Transfer [Default Data] | [Jon_Postel] | [Jon_Postel] | ||||||
| ftp-data | 20 | sctp | FTP | [Randall_Stewart] | [Randall_Stewart] | 2022-02-07 | [RFC 9260] | ||||
| smtp | 25 | tcp | Simple Mail Transfer | [IESG] | [IETF_Chair] | 2017-06-05 | [RFC-ietf-emailcore-rfc5321bis-43] | ||||
| smtp | 25 | udp | Simple Mail Transfer | [IESG] | [IETF_Chair] | 2017-06-05 | [RFC-ietf-emailcore-rfc5321bis-43] | ||||
| nsw-fe | 27 | tcp | NSW User System FE | [Robert_Thomas] | [Robert_Thomas] | ||||||
| nsw-fe | 27 | udp | NSW User System FE | [Robert_Thomas] | [Robert_Thomas] | ||||||
| msg-icp | 29 | tcp | MSG ICP | [Robert_Thomas] | [Robert_Thomas] | ||||||
| msg-icp | 29 | udp | MSG ICP | [Robert_Thomas] | [Robert_Thomas] | ||||||
| msg-auth | 31 | tcp | MSG Authentication | [Robert_Thomas] | [Robert_Thomas] | ||||||
| msg-auth | 31 | udp | MSG Authentication | [Robert_Thomas] | [Robert_Thomas] | ||||||
| mpm-flags | 44 | tcp | MPM FLAGS Protocol | ||||||||
| mpm-flags | 44 | udp | MPM FLAGS Protocol | ||||||||
| mpm-snd | 46 | tcp | MPM [default send] | [Jon_Postel] | [Jon_Postel] | ||||||
| mpm-snd | 46 | udp | MPM [default send] | [Jon_Postel] | [Jon_Postel] | ||||||
| 47 | tcp | Reserved | 2017-05-18 | This entry has been removed on 2017-05-18. | |||||||
| 47 | udp | Reserved | 2017-05-18 | This entry has been removed on 2017-05-18. | |||||||
| re-mail-ck | 50 | tcp | Remote Mail Checking Protocol | [Steve_Dorner] | [Steve_Dorner] | ||||||
| re-mail-ck | 50 | udp | Remote Mail Checking Protocol | [Steve_Dorner] | [Steve_Dorner] | ||||||
| 51 | Reserved | 2013-05-24 | This entry is being removed on 2013-05-24. | ||||||||
| xns-time | 52 | tcp | XNS Time Protocol | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| xns-time | 52 | udp | XNS Time Protocol | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| xns-ch | 54 | tcp | XNS Clearinghouse | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| xns-ch | 54 | udp | XNS Clearinghouse | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| isi-gl | 55 | tcp | ISI Graphics Language | ||||||||
| isi-gl | 55 | udp | ISI Graphics Language | ||||||||
| xns-auth | 56 | tcp | XNS Authentication | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| xns-auth | 56 | udp | XNS Authentication | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| xns-mail | 58 | tcp | XNS Mail | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| xns-mail | 58 | udp | XNS Mail | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| 61 | tcp | Reserved | 2017-05-18 | This entry has been removed on 2017-05-18. | |||||||
| 61 | udp | Reserved | 2017-05-18 | This entry has been removed on 2017-05-18. | |||||||
| tacacs-ds | 65 | tcp | TACACS-Database Service | [Kathy_Huber] | [Kathy_Huber] | ||||||
| tacacs-ds | 65 | udp | TACACS-Database Service | [Kathy_Huber] | [Kathy_Huber] | ||||||
| sql-net | 66 | tcp | Oracle SQL*NET IANA assigned this well-formed service name as a replacement for "sql*net". |
[Jack_Haverty] | [Jack_Haverty] | ||||||
| sql*net | 66 | tcp | Oracle SQL*NET | [Jack_Haverty] | [Jack_Haverty] | This entry is an alias to "sql-net". This entry is now historic, not usable for use with many common service discovery mechanisms. | |||||
| sql-net | 66 | udp | Oracle SQL*NET IANA assigned this well-formed service name as a replacement for "sql*net". |
[Jack_Haverty] | [Jack_Haverty] | ||||||
| sql*net | 66 | udp | Oracle SQL*NET | [Jack_Haverty] | [Jack_Haverty] | This entry is an alias to "sql-net". This entry is now historic, not usable for use with many common service discovery mechanisms. | |||||
| netrjs-1 | 71 | tcp | Remote Job Service | ||||||||
| netrjs-1 | 71 | udp | Remote Job Service | ||||||||
| netrjs-2 | 72 | tcp | Remote Job Service | ||||||||
| netrjs-2 | 72 | udp | Remote Job Service | ||||||||
| netrjs-3 | 73 | tcp | Remote Job Service | ||||||||
| netrjs-3 | 73 | udp | Remote Job Service | ||||||||
| netrjs-4 | 74 | tcp | Remote Job Service | [Bob_Braden] | [Bob_Braden] | ||||||
| netrjs-4 | 74 | udp | Remote Job Service | [Bob_Braden] | [Bob_Braden] | ||||||
| www-http | 80 | tcp | World Wide Web HTTP | [Tim_Berners_Lee] | [Tim_Berners_Lee] | This is a duplicate of the "http" service and should not be used for discovery purposes. u=<username> p=<password> path=<path to document> (see txtrecords.html#http) Known Subtypes: _printer NOTE: The meaning of this service type, though called just "http", actually denotes something more precise than just "any data transported using HTTP". The DNS-SD service type "http" should only be used to advertise content that: * is served over HTTP, * can be displayed by "typical" web browser client software, and * is intented primarily to be viewed by a human user. Of course, the definition of "typical web browser" is subjective, and may change over time, but for practical purposes the DNS-SD service type "http" can be understood as meaning "human-readable HTML content served over HTTP". In some cases other widely-supported content types may also be appropriate, such as plain text over HTTP, or JPEG image over HTTP. Content types not intented primarily for viewing by a human user, or not widely-supported in web browsing clients, should not be advertised as DNS-SD service type "http", even if they do happen to be transported over HTTP. Such types should be advertised as their own logical service type with their own DNS-SD service type, for example, XUL (XML User Interface Language) transported over HTTP is advertised explicitly as DNS-SD service type "xul-http". | |||||
| www-http | 80 | udp | World Wide Web HTTP | [Tim_Berners_Lee] | [Tim_Berners_Lee] | This is a duplicate of the "http" service and should not be used for discovery purposes. u=<username> p=<password> path=<path to document> (see txtrecords.html#http) Known Subtypes: _printer NOTE: The meaning of this service type, though called just "http", actually denotes something more precise than just "any data transported using HTTP". The DNS-SD service type "http" should only be used to advertise content that: * is served over HTTP, * can be displayed by "typical" web browser client software, and * is intented primarily to be viewed by a human user. Of course, the definition of "typical web browser" is subjective, and may change over time, but for practical purposes the DNS-SD service type "http" can be understood as meaning "human-readable HTML content served over HTTP". In some cases other widely-supported content types may also be appropriate, such as plain text over HTTP, or JPEG image over HTTP. Content types not intented primarily for viewing by a human user, or not widely-supported in web browsing clients, should not be advertised as DNS-SD service type "http", even if they do happen to be transported over HTTP. Such types should be advertised as their own logical service type with their own DNS-SD service type, for example, XUL (XML User Interface Language) transported over HTTP is advertised explicitly as DNS-SD service type "xul-http". | |||||
| mit-ml-dev | 83 | tcp | MIT ML Device | [David_Reed] | [David_Reed] | ||||||
| mit-ml-dev | 83 | udp | MIT ML Device | [David_Reed] | [David_Reed] | ||||||
| mit-ml-dev | 85 | tcp | MIT ML Device | [David_Reed] | [David_Reed] | ||||||
| mit-ml-dev | 85 | udp | MIT ML Device | [David_Reed] | [David_Reed] | ||||||
| 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] | ||||||
| mit-dov | 91 | tcp | MIT Dover Spooler | [Eliot_Moss] | [Eliot_Moss] | ||||||
| mit-dov | 91 | udp | MIT Dover Spooler | [Eliot_Moss] | [Eliot_Moss] | ||||||
| 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] | ||||||
| iso-tsap | 102 | tcp | ISO-TSAP Class 0 | [Marshall_Rose] | [Marshall_Rose] | ||||||
| iso-tsap | 102 | udp | ISO-TSAP Class 0 | [Marshall_Rose] | [Marshall_Rose] | ||||||
| gppitnp | 103 | tcp | Genesis Point-to-Point Trans Net | ||||||||
| gppitnp | 103 | udp | Genesis Point-to-Point Trans Net | ||||||||
| acr-nema | 104 | tcp | ACR-NEMA Digital Imag. & Comm. 300 | [Patrick_McNamee] | [Patrick_McNamee] | ||||||
| acr-nema | 104 | udp | ACR-NEMA Digital Imag. & Comm. 300 | [Patrick_McNamee] | [Patrick_McNamee] | ||||||
| csnet-ns | 105 | tcp | Mailbox Name Nameserver | [Marvin_Solomon] | [Marvin_Solomon] | ||||||
| csnet-ns | 105 | udp | Mailbox Name Nameserver | [Marvin_Solomon] | [Marvin_Solomon] | ||||||
| 3com-tsmux | 106 | tcp | 3COM-TSMUX | [Jeremy_Siegel] | [Jeremy_Siegel] | Known Unauthorized Use on 106 | |||||
| 3com-tsmux | 106 | udp | 3COM-TSMUX | [Jeremy_Siegel] | [Jeremy_Siegel] | Known Unauthorized Use on 106 | |||||
| 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] | ||||||
| pop3 | 110 | tcp | Post Office Protocol - Version 3 | [Marshall_Rose] | [Marshall_Rose] | ||||||
| pop3 | 110 | udp | Post Office Protocol - Version 3 | [Marshall_Rose] | [Marshall_Rose] | ||||||
| uucp-path | 117 | tcp | UUCP Path Service | ||||||||
| uucp-path | 117 | udp | UUCP Path Service | ||||||||
| locus-map | 125 | tcp | Locus PC-Interface Net Map Ser | [Eric_Peterson] | [Eric_Peterson] | ||||||
| locus-map | 125 | udp | Locus PC-Interface Net Map Ser | [Eric_Peterson] | [Eric_Peterson] | ||||||
| locus-con | 127 | tcp | Locus PC-Interface Conn Server | [Eric_Peterson] | [Eric_Peterson] | ||||||
| locus-con | 127 | udp | Locus PC-Interface Conn Server | [Eric_Peterson] | [Eric_Peterson] | ||||||
| gss-xlicen | 128 | tcp | GSS X License Verification | [John_Light] | [John_Light] | ||||||
| gss-xlicen | 128 | udp | GSS X License Verification | [John_Light] | [John_Light] | ||||||
| cisco-fna | 130 | tcp | cisco FNATIVE | ||||||||
| cisco-fna | 130 | udp | cisco FNATIVE | ||||||||
| cisco-tna | 131 | tcp | cisco TNATIVE | ||||||||
| cisco-tna | 131 | udp | cisco TNATIVE | ||||||||
| cisco-sys | 132 | tcp | cisco SYSMAINT | ||||||||
| cisco-sys | 132 | udp | cisco SYSMAINT | ||||||||
| ingres-net | 134 | tcp | INGRES-NET Service | [Mike_Berrow] | [Mike_Berrow] | ||||||
| ingres-net | 134 | udp | INGRES-NET Service | [Mike_Berrow] | [Mike_Berrow] | ||||||
| netbios-ns | 137 | tcp | NETBIOS Name Service | ||||||||
| netbios-ns | 137 | udp | NETBIOS Name Service | ||||||||
| netbios-dgm | 138 | tcp | NETBIOS Datagram Service | ||||||||
| netbios-dgm | 138 | udp | NETBIOS Datagram Service | ||||||||
| netbios-ssn | 139 | tcp | NETBIOS Session Service | [Jon_Postel] | [Jon_Postel] | ||||||
| netbios-ssn | 139 | udp | NETBIOS Session Service | [Jon_Postel] | [Jon_Postel] | ||||||
| emfis-data | 140 | tcp | EMFIS Data Service | ||||||||
| emfis-data | 140 | udp | EMFIS Data Service |