Service Name and Transport Protocol Port Number Registry
- Last Updated
- 2025-11-20
- 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
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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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 4 | tcp | Unassigned | |||||||||
| 4 | udp | Unassigned | |||||||||
| discard | 9 | dccp | Discard | [Eddie_Kohler] | [Eddie_Kohler] | [RFC4340] | 1145656131 | ||||
| 14 | tcp | Unassigned | |||||||||
| 14 | udp | Unassigned | |||||||||
| ssh | 22 | tcp | The Secure Shell (SSH) Protocol | [RFC4251] | Defined TXT keys: u=<username> p=<password> | ||||||
| ssh | 22 | udp | The Secure Shell (SSH) Protocol | [RFC4251] | Defined TXT keys: u=<username> p=<password> | ||||||
| telnet | 23 | tcp | Telnet | [Jon_Postel] | [Jon_Postel] | [RFC854] | Defined TXT keys: u=<username> p=<password> | ||||
| telnet | 23 | udp | Telnet | [Jon_Postel] | [Jon_Postel] | [RFC854] | Defined TXT keys: u=<username> p=<password> | ||||
| 24 | tcp | any private mail system | [Rick_Adams] | [Rick_Adams] | |||||||
| 24 | udp | any private mail system | [Rick_Adams] | [Rick_Adams] | |||||||
| 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] | ||||
| 34 | tcp | Unassigned | |||||||||
| 34 | udp | Unassigned | |||||||||
| 40 | tcp | Unassigned | |||||||||
| 40 | udp | Unassigned | |||||||||
| graphics | 41 | tcp | Graphics | ||||||||
| graphics | 41 | udp | Graphics | ||||||||
| name | 42 | tcp | Host Name Server | ||||||||
| name | 42 | udp | Host Name Server | ||||||||
| nameserver | 42 | tcp | Host Name Server | ||||||||
| nameserver | 42 | udp | Host Name Server | ||||||||
| nicname | 43 | tcp | Who Is | ||||||||
| nicname | 43 | udp | Who Is | ||||||||
| mpm-flags | 44 | tcp | MPM FLAGS Protocol | ||||||||
| mpm-flags | 44 | udp | MPM FLAGS Protocol | ||||||||
| mpm | 45 | tcp | Message Processing Module [recv] | ||||||||
| mpm | 45 | udp | Message Processing Module [recv] | ||||||||
| 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. | |||||||
| auditd | 48 | tcp | Digital Audit Daemon | [Larry_Scott] | [Larry_Scott] | ||||||
| auditd | 48 | udp | Digital Audit Daemon | [Larry_Scott] | [Larry_Scott] | ||||||
| tacacs | 49 | tcp | Login Host Protocol (TACACS) | [Pieter_Ditmars] | [Pieter_Ditmars] | ||||||
| tacacs | 49 | udp | Login Host Protocol (TACACS) | [Pieter_Ditmars] | [Pieter_Ditmars] | ||||||
| 51 | Reserved | 2013-05-24 | This entry is being removed on 2013-05-24. | ||||||||
| xns-ch | 54 | tcp | XNS Clearinghouse | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| xns-ch | 54 | udp | XNS Clearinghouse | [Susie_Armstrong] | [Susie_Armstrong] | ||||||
| covia | 64 | tcp | Communications Integrator (CI) | [Dan_Smith] | [Dan_Smith] | ||||||
| covia | 64 | udp | Communications Integrator (CI) | [Dan_Smith] | [Dan_Smith] | ||||||
| netrjs-4 | 74 | tcp | Remote Job Service | [Bob_Braden] | [Bob_Braden] | ||||||
| netrjs-4 | 74 | udp | Remote Job Service | [Bob_Braden] | [Bob_Braden] | ||||||
| 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) | |||||
| ctf | 84 | tcp | Common Trace Facility | [Hugh_Thomas] | [Hugh_Thomas] | ||||||
| ctf | 84 | udp | Common Trace Facility | [Hugh_Thomas] | [Hugh_Thomas] | ||||||
| kerberos | 88 | tcp | Kerberos | [B_Clifford_Neuman] | [B_Clifford_Neuman] | 2022-02-18 | [RFC4120] | ||||
| kerberos | 88 | udp | Kerberos | [B_Clifford_Neuman] | [B_Clifford_Neuman] | 2022-02-18 | [RFC4120] | ||||
| objcall | 94 | tcp | Tivoli Object Dispatcher | [Tom_Bereiter] | [Tom_Bereiter] | ||||||
| objcall | 94 | udp | Tivoli Object Dispatcher | [Tom_Bereiter] | [Tom_Bereiter] | ||||||
| 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] | ||||||
| 114 | unassigned | Deprecated June 2004 | |||||||||
| ansatrader | 124 | tcp | ANSA REX Trader | [Nicola_J_Howarth] | [Nicola_J_Howarth] | ||||||
| ansatrader | 124 | udp | ANSA REX Trader | [Nicola_J_Howarth] | [Nicola_J_Howarth] | ||||||
| ingres-net | 134 | tcp | INGRES-NET Service | [Mike_Berrow] | [Mike_Berrow] | ||||||
| ingres-net | 134 | udp | INGRES-NET Service | [Mike_Berrow] | [Mike_Berrow] | ||||||
| emfis-data | 140 | tcp | EMFIS Data Service | ||||||||
| emfis-data | 140 | udp | EMFIS Data Service | ||||||||
| emfis-cntl | 141 | tcp | EMFIS Control Service | [Gerd_Beling] | [Gerd_Beling] | ||||||
| emfis-cntl | 141 | udp | EMFIS Control Service | [Gerd_Beling] | [Gerd_Beling] | ||||||
| bl-idm | 142 | tcp | Britton-Lee IDM | [Susie_Snitzer] | [Susie_Snitzer] | ||||||
| bl-idm | 142 | udp | Britton-Lee IDM | [Susie_Snitzer] | [Susie_Snitzer] | ||||||
| imap | 143 | tcp | Internet Message Access Protocol | [IESG] | [IETF_Chair] | 2021-02-22 | [RFC3501][RFC9051] | ||||
| 143 | udp | Reserved | 2021-02-22 | [RFC9051] | |||||||
| uma | 144 | tcp | Universal Management Architecture | [Jay_Whitney] | [Jay_Whitney] | ||||||
| uma | 144 | udp | Universal Management Architecture | [Jay_Whitney] | [Jay_Whitney] | ||||||
| uaac | 145 | tcp | UAAC Protocol | [David_A_Gomberg] | [David_A_Gomberg] | ||||||
| uaac | 145 | udp | UAAC Protocol | [David_A_Gomberg] | [David_A_Gomberg] | ||||||
| iso-tp0 | 146 | tcp | ISO-IP0 | ||||||||
| iso-tp0 | 146 | udp | ISO-IP0 | ||||||||
| iso-ip | 147 | tcp | ISO-IP | [Marshall_Rose] | [Marshall_Rose] | ||||||
| iso-ip | 147 | udp | ISO-IP | [Marshall_Rose] | [Marshall_Rose] | ||||||
| jargon | 148 | tcp | Jargon | [Bill_Weinman] | [Bill_Weinman] | ||||||
| jargon | 148 | udp | Jargon | [Bill_Weinman] | [Bill_Weinman] | ||||||
| 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] | ||||||
| netsc-prod | 154 | tcp | NETSC | ||||||||
| netsc-prod | 154 | udp | NETSC | ||||||||
| cmip-agent | 164 | tcp | CMIP/TCP Agent | [Amatzia_Ben_Artzi] | [Amatzia_Ben_Artzi] | ||||||
| cmip-agent | 164 | udp | CMIP/TCP Agent | [Amatzia_Ben_Artzi] | [Amatzia_Ben_Artzi] | ||||||
| mailq | 174 | tcp | MAILQ | [Rayan_Zachariassen] | [Rayan_Zachariassen] | ||||||
| mailq | 174 | udp | MAILQ | [Rayan_Zachariassen] | [Rayan_Zachariassen] | ||||||
| ocserver | 184 | tcp | OCServer | [Jerrilynn_Okamura] | [Jerrilynn_Okamura] | ||||||
| ocserver | 184 | udp | OCServer | [Jerrilynn_Okamura] | [Jerrilynn_Okamura] | ||||||
| irc | 194 | tcp | Internet Relay Chat Protocol | [Jarkko_Oikarinen] | [Jarkko_Oikarinen] | ||||||
| irc | 194 | udp | Internet Relay Chat Protocol | [Jarkko_Oikarinen] | [Jarkko_Oikarinen] | ||||||
| at-echo | 204 | tcp | AppleTalk Echo | ||||||||
| at-echo | 204 | udp | AppleTalk Echo | ||||||||
| 914c-g | 211 | tcp | Texas Instruments 914C/G Terminal IANA assigned this well-formed service name as a replacement for "914c/g". |
[Bill_Harrell] | [Bill_Harrell] | ||||||
| 914c/g | 211 | tcp | Texas Instruments 914C/G Terminal | [Bill_Harrell] | [Bill_Harrell] | This entry is an alias to "914c-g". This entry is now historic, not usable for use with many common service discovery mechanisms. | |||||
| 914c-g | 211 | udp | Texas Instruments 914C/G Terminal IANA assigned this well-formed service name as a replacement for "914c/g". |
[Bill_Harrell] | [Bill_Harrell] | ||||||
| 914c/g | 211 | udp | Texas Instruments 914C/G Terminal | [Bill_Harrell] | [Bill_Harrell] | This entry is an alias to "914c-g". This entry is now historic, not usable for use with many common service discovery mechanisms. | |||||
| vmpwscs | 214 | tcp | VM PWSCS | [Dan_Shia] | [Dan_Shia] | ||||||
| vmpwscs | 214 | udp | VM PWSCS | [Dan_Shia] | [Dan_Shia] | ||||||
| masqdialer | 224 | tcp | masqdialer | [Charles_Wright] | [Charles_Wright] | Possible Conflict of Port 222 with "Masqdialer" | |||||
| masqdialer | 224 | udp | masqdialer | [Charles_Wright] | [Charles_Wright] | Possible Conflict of Port 222 with "Masqdialer" | |||||
| 225-241 | Reserved | 2024-12-20 | [RFC1060] |