Service Name and Transport Protocol Port Number Registry
- Last Updated
- 2026-02-13
- 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| 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] | ||||
| http | 80 | tcp | World Wide Web HTTP | [IESG] | [IETF_Chair] | 2021-10-01 | [RFC9110] | Defined TXT keys: u=<username> p=<password> path=<path to document> | |||
| http | 80 | udp | World Wide Web HTTP | [IESG] | [IETF_Chair] | 2021-10-01 | [RFC9110] | Defined TXT keys: u=<username> p=<password> path=<path to document> | |||
| www | 80 | tcp | World Wide Web HTTP | [IESG] | [IETF_Chair] | 2021-10-01 | [RFC9110] | 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 | [RFC9110] | This is a duplicate of the "http" service and should not be used for discovery purposes. | |||
| nntp | 119 | tcp | Network News Transfer Protocol | [IESG] | [IETF_Chair] | 2018-07-06 | [RFC3977] | ||||
| nntp | 119 | udp | Network News Transfer Protocol | [IESG] | [IETF_Chair] | 2018-07-06 | [RFC3977] | ||||
| imap | 143 | tcp | Internet Message Access Protocol | [IESG] | [IETF_Chair] | 2021-02-22 | [RFC3501][RFC9051] | ||||
| pt-tls | 271 | tcp | IETF Network Endpoint Assessment (NEA) Posture Transport Protocol over TLS (PT-TLS) | [IESG] | [IETF_Chair] | 2012-07-31 | [RFC6876] | ||||
| tacacss | 300 | tcp | TLS Secure Login Host Protocol (TACACSS) | [IESG] | [IETF_Chair] | 2025-07-15 | [RFC9887] | ||||
| rpki-rtr | 323 | tcp | Resource PKI to Router Protocol | [IESG] | [IETF_Chair] | [RFC6810] | |||||
| rpki-rtr-tls | 324 | tcp | Resource PKI to Router Protocol over TLS | [IESG] | [IETF_Chair] | [RFC6810] | |||||
| nnsp | 433 | tcp | NNTP for transit servers (NNSP) | [IESG] | [IETF_Chair] | 2018-07-06 | [RFC3977] | ||||
| nnsp | 433 | udp | NNTP for transit servers (NNSP) | [IESG] | [IETF_Chair] | 2018-07-06 | [RFC3977] | ||||
| https | 443 | tcp | http protocol over TLS/SSL | [IESG] | [IETF_Chair] | 2021-10-01 | [RFC9110] | ||||
| https | 443 | udp | http protocol over TLS/SSL | [IESG] | [IETF_Chair] | 2021-10-01 | [RFC9110] | ||||
| submissions | 465 | tcp | Message Submission over TLS protocol | [IESG] | [IETF_Chair] | 2017-12-12 | [RFC8314] | ||||
| dhcpv6-client | 546 | udp | DHCPv6 Client | [IESG] | [IETF_Chair] | 2018-05-21 | [RFC9915] | ||||
| dhcpv6-server | 547 | tcp | DHCPv6 Server | [IESG] | [IETF_Chair] | 2018-05-21 | [RFC5460] | ||||
| dhcpv6-server | 547 | udp | DHCPv6 Server | [IESG] | [IETF_Chair] | 2018-05-21 | [RFC9915] | ||||
| nntps | 563 | tcp | nntp protocol over TLS/SSL (was snntp) | [IESG] | [IETF_Chair] | 2018-07-06 | [RFC4642] | ||||
| nntps | 563 | udp | nntp protocol over TLS/SSL (was snntp) | [IESG] | [IETF_Chair] | 2018-07-06 | [RFC4642] | ||||
| ipp | 631 | tcp | IPP (Internet Printing Protocol) | [IESG] | [IETF_Chair] | 2018-07-06 | [RFC8011] | Defined TXT keys: See BonjourPrinting.pdf. | |||
| ipp | 631 | udp | IPP (Internet Printing Protocol) | [IESG] | [IETF_Chair] | 2018-07-06 | [RFC8011] | Defined TXT keys: See BonjourPrinting.pdf. | |||
| ipps | 631 | tcp | Internet Printing Protocol over HTTPS | [IESG] | [IETF_Chair] | 2018-07-06 | [RFC8011] | ||||
| dhcp-failover | 647 | tcp | DHCP Failover | [IESG] | [IETF_Chair] | 2018-05-21 | [RFC8156] | ||||
| domain-s | 853 | tcp | DNS query-response protocol run over TLS | [IESG] | [IETF_Chair] | 2015-10-08 | 2022-04-11 | [RFC7858] | |||
| domain-s | 853 | udp | DNS query-response protocol run over DTLS or QUIC | [IESG] | [IETF_Chair] | 2015-10-08 | 2022-04-01 | [RFC7858][RFC8094][RFC9250] | |||
| dlep | 854 | tcp | Dynamic Link Exchange Protocol (DLEP) | [IESG] | [IETF_Chair] | 2017-04-03 | [RFC8175] | ||||
| dlep | 854 | udp | Dynamic Link Exchange Protocol (DLEP) | [IESG] | [IETF_Chair] | 2017-04-03 | [RFC8175] | ||||
| iscsi | 860 | tcp | iSCSI | [IESG] | [IETF_Chair] | 2013-08-27 | [RFC7143] | ||||
| iscsi | 860 | udp | iSCSI | [IESG] | [IETF_Chair] | 2013-08-27 | [RFC7143] | ||||
| owamp-control | 861 | tcp | OWAMP-Control | [IESG] | [IETF_Chair] | [RFC4656] | |||||
| owamp-test | 861 | udp | OWAMP-Test | [IESG] | [IETF_Chair] | 2018-12-21 | [RFC8545] | ||||
| twamp-control | 862 | tcp | TWAMP-Control | [IESG] | [IETF_Chair] | [RFC5357] | |||||
| twamp-test | 862 | udp | TWAMP-Test Receiver Port | [IESG] | [IETF_Chair] | 2018-12-21 | [RFC8545] | ||||
| rift-lies | 914 | udp | Routing in Fat Trees Link Information Element | [IESG] | [IETF_Chair] | 2023-02-17 | 2024-06-07 | [RFC9692] | |||
| rift-ties | 915 | udp | Routing in Fat Trees Topology Information Element | [IESG] | [IETF_Chair] | 2023-02-17 | 2024-06-07 | [RFC9692] | |||
| imaps | 993 | tcp | IMAP over TLS protocol | [IESG] | [IETF_Chair] | 2021-02-22 | [RFC3501][RFC8314][RFC9051] | ||||
| pop3s | 995 | tcp | POP3 over TLS protocol | [IESG] | [IETF_Chair] | 2017-12-12 | [RFC8314] | ||||
| webpush | 1001 | tcp | HTTP Web Push | [IESG] | [IETF_Chair] | 2016-11-01 | [RFC8030] | ||||
| exp1 | 1021 | tcp | RFC3692-style Experiment 1 | [IESG] | [IETF_Chair] | [1][RFC4727][RFC6335] | |||||
| exp1 | 1021 | udp | RFC3692-style Experiment 1 | [IESG] | [IETF_Chair] | [1][RFC4727][RFC6335] | |||||
| exp1 | 1021 | sctp | RFC3692-style Experiment 1 | [IESG] | [IETF_Chair] | [1][RFC4727][RFC6335] | |||||
| exp1 | 1021 | dccp | RFC3692-style Experiment 1 | [IESG] | [IETF_Chair] | [1][RFC4727][RFC6335] | |||||
| exp2 | 1022 | tcp | RFC3692-style Experiment 2 | [IESG] | [IETF_Chair] | [1][RFC4727][RFC6335] | |||||
| exp2 | 1022 | udp | RFC3692-style Experiment 2 | [IESG] | [IETF_Chair] | [1][RFC4727][RFC6335] | |||||
| exp2 | 1022 | sctp | RFC3692-style Experiment 2 | [IESG] | [IETF_Chair] | [1][RFC4727][RFC6335] | |||||
| exp2 | 1022 | dccp | RFC3692-style Experiment 2 | [IESG] | [IETF_Chair] | [1][RFC4727][RFC6335] | |||||
| 6a44 | 1027 | udp | IPv6 Behind NAT44 CPEs | [IESG] | [IETF_Chair] | 2012-08-02 | [RFC6751] | ||||
| radsec | 2083 | tcp | Secure Radius Service | [IESG] | [IETF_Chair] | 2005-05 | [RFC6614] | The TCP port 2083 was already previously assigned by IANA for "RadSec", an early implementation of RADIUS/TLS, prior to issuance of this RFC. This early implementation can be configured to be compatible to RADIUS/TLS as specified by the IETF. See [RFC6614], Appendix A for details. | |||
| radsec | 2083 | udp | Secure Radius Service | [IESG] | [IETF_Chair] | 2005-05 | 2014-07-14 | [RFC7360] | The UDP port 2083 was already previously assigned by IANA for "RadSec", an early implementation of RADIUS/TLS, prior to issuance of this RFC. | ||
| amt | 2268 | tcp | AMT | [IESG] | [IETF_Chair] | 2004-12 | 2014-12-17 | [RFC7450] | |||
| amt | 2268 | udp | AMT | [IESG] | [IETF_Chair] | 2004-12 | 2014-12-17 | [RFC7450] | |||
| iscsi-target | 3260 | tcp | iSCSI port | [IESG] | [IETF_Chair] | 2013-08-27 | [RFC7143] | ||||
| iscsi-target | 3260 | udp | iSCSI port | [IESG] | [IETF_Chair] | 2013-08-27 | [RFC7143] | ||||
| stun | 3478 | tcp | Session Traversal Utilities for NAT (STUN) port | [IESG] | [IETF_Chair] | 2019-03-28 | [RFC8489] | ||||
| stun | 3478 | udp | Session Traversal Utilities for NAT (STUN) port | [IESG] | [IETF_Chair] | 2019-03-28 | [RFC8489] | ||||
| netconf-ch-ssh | 4334 | tcp | NETCONF Call Home (SSH) | [IESG] | [IETF_Chair] | 2016-01-12 | [RFC8071] | ||||
| netconf-ch-tls | 4335 | tcp | NETCONF Call Home (TLS) | [IESG] | [IETF_Chair] | 2016-01-12 | [RFC8071] | ||||
| restconf-ch-tls | 4336 | tcp | RESTCONF Call Home (TLS) | [IESG] | [IETF_Chair] | 2016-01-12 | [RFC8071] | ||||
| lisp-data | 4341 | udp | LISP Data Packets | [IESG] | [IETF_Chair] | 2007-11-12 | 2021-02-17 | [RFC9300] | |||
| lisp-control | 4342 | udp | LISP Control Packets | [IETF] | [IESG] | 2007-05 | 2021-02-25 | [RFC9301] | |||
| ntske | 4460 | tcp | Network Time Security Key Establishment | [IESG] | [IETF_Chair] | 2020-04-07 | [RFC8915] | ||||
| dtn-bundle | 4556 | tcp | DTN Bundle TCP CL Protocol | [IESG] | [IETF_Chair] | 2021-02-22 | [RFC9174] | ||||
| rid | 4590 | tcp | RID over HTTP/TLS | [IESG] | [IETF_Chair] | [RFC6546] | |||||
| dots-signal | 4646 | tcp | Distributed Denial-of-Service Open Threat Signaling (DOTS) Signal Channel Protocol. The service name is used to construct the SRV service names "_dots-signal._udp" and "_dots-signal._tcp" for discovering DOTS servers used to establish DOTS signal channel. | [IESG] | [IETF_Chair] | 2020-01-16 | 2021-06-14 | [RFC8973][RFC9132] | |||
| dots-signal | 4646 | udp | Distributed Denial-of-Service Open Threat Signaling (DOTS) Signal Channel Protocol. The service name is used to construct the SRV service names "_dots-signal._udp" and "_dots-signal._tcp" for discovering DOTS servers used to establish DOTS signal channel. | [IESG] | [IETF_Chair] | 2020-01-16 | 2021-06-14 | [RFC8973][RFC9132] | |||
| gre-in-udp | 4754 | udp | GRE-in-UDP Encapsulation | [IESG] | [IETF_Chair] | 2016-10-05 | [RFC8086] | ||||
| gre-udp-dtls | 4755 | udp | GRE-in-UDP Encapsulation with DTLS | [IESG] | [IETF_Chair] | 2016-10-05 | [RFC8086] | ||||
| pkix-cmc | 5318 | tcp | PKIX Certificate Management using CMS (CMC) | [IESG] | [IETF_Chair] | 2026-02-13 | [RFC-ietf-lamps-rfc5273bis-10] | ||||
| stuns | 5349 | tcp | Session Traversal Utilities for NAT (STUN) port | [IESG] | [IETF_Chair] | 2019-03-28 | [RFC8489] | ||||
| stuns | 5349 | udp | STUN over DTLS | [IESG] | [IETF_Chair] | 2014-07-03 | [RFC7350] | This service name was initially created by [RFC5389]. | |||
| turns | 5349 | udp | TURN over DTLS | [IESG] | [IETF_Chair] | 2019-08-02 | [RFC7350] | This service name was initially created by [RFC8656]. | |||
| pcp-multicast | 5350 | udp | Port Control Protocol Multicast | [IESG] | [IETF_Chair] | [RFC6887] | |||||
| pcp | 5351 | udp | Port Control Protocol | [IESG] | [IETF_Chair] | [RFC6887] | |||||
| mdns | 5353 | tcp | Multicast DNS | [IESG] | [IETF_Chair] | [RFC6762] | |||||
| mdns | 5353 | udp | Multicast DNS | [IESG] | [IETF_Chair] | [RFC6762] | |||||
| coap | 5683 | tcp | Constrained Application Protocol (CoAP) | [IESG] | [IETF_Chair] | 2017-12-22 | [RFC8323] | ||||
| coap | 5683 | udp | Constrained Application Protocol | [IESG] | [IETF_Chair] | 2011-06-13 | 2013-07-25 | [RFC7252] | |||
| coaps | 5684 | tcp | Constrained Application Protocol (CoAP) | [IESG] | [IETF_Chair] | 2017-12-22 | [RFC7301][RFC8323] | ||||
| coaps | 5684 | udp | DTLS-secured CoAP | [IESG] | [IETF_Chair] | 2013-07-25 | [RFC7252] | ||||
| diameters | 5868 | tcp | Diameter over TLS/TCP | [IESG] | [IETF_Chair] | [RFC6733] | |||||
| diameters | 5868 | sctp | Diameter over DTLS/SCTP | [IESG] | [IETF_Chair] | [RFC6733] | |||||
| geneve | 6081 | udp | Generic Network Virtualization Encapsulation (Geneve) | [IESG] | [IETF_Chair] | 2014-03-27 | 2020-05-04 | [RFC8926] | |||
| reload-config | 6084 | tcp | Peer to Peer Infrastructure Configuration | [IESG] | [IETF_Chair] | 2009-01-29 | 2013-03-26 | [RFC6940] | |||
| dccp-udp | 6511 | udp | Datagram Congestion Control Protocol Encapsulation for NAT Traversal | [IESG] | [IETF_Chair] | [RFC6773] | |||||
| netconf-tls | 6513 | tcp | NETCONF over TLS | [IESG] | [IETF_Chair] | 2024-01-24 | [RFC7589][RFC-ietf-netconf-over-tls13-04] | ||||
| mpls-udp | 6635 | udp | Encapsulate MPLS packets in UDP tunnels. | [IESG] | [IETF_Chair] | 2015-02-10 | [RFC7510] | ||||
| mpls-udp-dtls | 6636 | udp | Encapsulate MPLS packets in UDP tunnels with DTLS. | [IESG] | [IETF_Chair] | 2015-02-10 | [RFC7510] | ||||
| babel-dtls | 6699 | udp | Babel Routing Protocol over DTLS | [IESG] | [IETF_Chair] | 2020-09-04 | [RFC8968] | ||||
| bfd-lag | 6784 | udp | Bidirectional Forwarding Detection (BFD) on Link Aggregation Group (LAG) Interfaces | [IESG] | [BFD_Chairs] | 2012-11-08 | 2014-01-09 | [RFC7130] | |||
| grasp | 7017 | tcp | GeneRic Autonomic Signaling Protocol | [IESG] | [IETF_Chair] | 2017-04-28 | 2017-07-20 | [RFC8990] | |||
| grasp | 7017 | udp | GeneRic Autonomic Signaling Protocol | [IESG] | [IETF_Chair] | 2017-04-28 | 2017-07-20 | [RFC8990] | |||
| s-bfd | 7784 | udp | Seamless Bidirectional Forwarding Detection (S-BFD) | [IESG] | [IETF_Chair] | 2014-12-24 | 2016-07-14 | [RFC7881] | |||
| mipv6tls | 7872 | udp | TLS-based Mobile IPv6 Security | [IESG] | [IETF_Chair] | 2012-04-12 | [RFC6618] | ||||
| aero | 8060 | udp | Asymmetric Extended Route Optimization (AERO) | [IESG] | [IETF_Chair] | [RFC6706] | |||||
| hncp-udp-port | 8231 | udp | HNCP | [IESG] | [IETF_Chair] | 2016-01-13 | [RFC7788] | ||||
| hncp-dtls-port | 8232 | udp | HNCP over DTLS | [IESG] | [IETF_Chair] | 2016-01-13 | [RFC7788] |
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Contact Information
| ID | Name | Organization | Contact URI | Last Updated |
|---|---|---|---|---|
| [BFD_Chairs] | IETF BFD Working Group Chairs | mailto:bfd-chairs&tools.ietf.org | 2014-01-09 | |
| [IESG] | IESG | mailto:iesg&ietf.org | ||
| [IETF] | IETF | mailto:iesg&ietf.org | ||
| [IETF_Chair] | IETF Chair | IETF | mailto:chair&ietf.org |