| retrospect | 497 | tcp | Retrospect backup and restore service | [Retrospect_Inc] | [JG_Heithcock] |  | 2012-02-02 |  |  |  |  | 
          
            | retrospect | 497 | udp | Retrospect backup and restore service | [Retrospect_Inc] | [JG_Heithcock] |  | 2012-02-02 |  |  |  |  | 
          
            | siam | 498 | tcp | siam | [Philippe_Gilbert] | [Philippe_Gilbert] |  |  |  |  |  |  | 
          
            | siam | 498 | udp | siam | [Philippe_Gilbert] | [Philippe_Gilbert] |  |  |  |  |  |  | 
          
            | iso-ill | 499 | tcp | ISO ILL Protocol | [Mark_H_Needleman] | [Mark_H_Needleman] |  |  |  |  |  |  | 
          
            | iso-ill | 499 | udp | ISO ILL Protocol | [Mark_H_Needleman] | [Mark_H_Needleman] |  |  |  |  |  |  | 
          
            | isakmp | 500 | tcp | isakmp | [Mark_Schertler] | [Mark_Schertler] |  |  |  |  |  |  | 
          
            | isakmp | 500 | udp | isakmp | [Mark_Schertler] | [Mark_Schertler] |  |  |  |  |  |  | 
          
            | stmf | 501 | tcp | STMF | [Alan_Ungar] | [Alan_Ungar] |  |  |  |  |  |  | 
          
            | stmf | 501 | udp | STMF | [Alan_Ungar] | [Alan_Ungar] |  |  |  |  |  |  | 
          
            | mbap | 502 | tcp | Modbus Application Protocol | [modbus.org] | [Dennis_Dube] |  | 2014-06-10 |  |  |  |  | 
          
            | mbap | 502 | udp | Modbus Application Protocol | [modbus.org] | [Dennis_Dube] |  | 2014-06-10 |  |  |  |  | 
          
            | intrinsa | 503 | tcp | Intrinsa | [Robert_Ford] | [Robert_Ford] |  |  |  |  |  |  | 
          
            | intrinsa | 503 | udp | Intrinsa | [Robert_Ford] | [Robert_Ford] |  |  |  |  |  |  | 
          
            | citadel | 504 | tcp | citadel | [Art_Cancro] | [Art_Cancro] |  |  |  |  |  |  | 
          
            | citadel | 504 | udp | citadel | [Art_Cancro] | [Art_Cancro] |  |  |  |  |  |  | 
          
            | mailbox-lm | 505 | tcp | mailbox-lm | [Beverly_Moody] | [Beverly_Moody] |  |  |  |  |  |  | 
          
            | mailbox-lm | 505 | udp | mailbox-lm | [Beverly_Moody] | [Beverly_Moody] |  |  |  |  |  |  | 
          
            | ohimsrv | 506 | tcp | ohimsrv | [Scott_Powell] | [Scott_Powell] |  |  |  |  |  |  | 
          
            | ohimsrv | 506 | udp | ohimsrv | [Scott_Powell] | [Scott_Powell] |  |  |  |  |  |  | 
          
            | crs | 507 | tcp | crs | [Brad_Wright] | [Brad_Wright] |  |  |  |  |  |  | 
          
            | crs | 507 | udp | crs | [Brad_Wright] | [Brad_Wright] |  |  |  |  |  |  | 
          
            | xvttp | 508 | tcp | xvttp | [Keith_J_Alphonso] | [Keith_J_Alphonso] |  |  |  |  |  |  | 
          
            | xvttp | 508 | udp | xvttp | [Keith_J_Alphonso] | [Keith_J_Alphonso] |  |  |  |  |  |  | 
          
            | snare | 509 | tcp | snare | [Dennis_Batchelder] | [Dennis_Batchelder] |  |  |  |  |  |  | 
          
            | snare | 509 | udp | snare | [Dennis_Batchelder] | [Dennis_Batchelder] |  |  |  |  |  |  | 
          
            | fcp | 510 | tcp | FirstClass Protocol | [Mike_Marshburn] | [Mike_Marshburn] |  |  |  |  |  |  | 
          
            | fcp | 510 | udp | FirstClass Protocol | [Mike_Marshburn] | [Mike_Marshburn] |  |  |  |  |  |  | 
          
            | passgo | 511 | tcp | PassGo | [John_Rainford] | [John_Rainford] |  |  |  |  |  |  | 
          
            | passgo | 511 | udp | PassGo | [John_Rainford] | [John_Rainford] |  |  |  |  |  |  | 
          
            | exec | 512 | tcp | remote process execution; authentication performed using passwords and UNIX login names |  |  |  |  |  |  |  |  | 
          
            | comsat | 512 | udp |  |  |  |  |  |  |  |  |  | 
          
            | biff | 512 | udp | used by mail system to notify users of new mail received; currently receives messages only from processes on the same machine |  |  |  |  |  |  |  |  | 
          
            | login | 513 | tcp | remote login a la telnet; automatic authentication performed based on priviledged port numbers and distributed data bases which identify "authentication domains" |  |  |  |  |  |  |  |  | 
          
            | who | 513 | udp | maintains data bases showing who's logged in to machines on a local net and the load average of the machine |  |  |  |  |  |  |  |  | 
          
            | shell | 514 | tcp | cmd like exec, but automatic authentication is performed as for login server |  |  |  |  |  |  |  |  | 
          
            | syslog | 514 | udp |  |  |  |  | 2020-06-01 | [RFC5426] |  |  |  | 
          
            | printer | 515 | tcp | spooler |  |  |  |  |  |  |  |  | 
          
            | printer | 515 | udp | spooler |  |  |  |  |  |  |  |  | 
          
            | videotex | 516 | tcp | videotex | [Daniel_Mavrakis] | [Daniel_Mavrakis] |  |  |  |  |  |  | 
          
            | videotex | 516 | udp | videotex | [Daniel_Mavrakis] | [Daniel_Mavrakis] |  |  |  |  |  |  | 
          
            | talk | 517 | tcp | like tenex link, but across machine - unfortunately, doesn't use link protocol (this is actually just a rendezvous port from which a tcp connection is established) |  |  |  |  |  |  |  |  | 
          
            | talk | 517 | udp | like tenex link, but across machine - unfortunately, doesn't use link protocol (this is actually just a rendezvous port from which a tcp connection is established) |  |  |  |  |  |  |  |  | 
          
            | ntalk | 518 | tcp |  |  |  |  |  |  |  |  |  | 
          
            | ntalk | 518 | udp |  |  |  |  |  |  |  |  |  | 
          
            | utime | 519 | tcp | unixtime |  |  |  |  |  |  |  |  | 
          
            | utime | 519 | udp | unixtime |  |  |  |  |  |  |  |  | 
          
            | 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] |  |  |  |  |  |  | 
          
            | courier | 530 | tcp | rpc |  |  |  |  |  |  |  |  | 
          
            | courier | 530 | udp | rpc |  |  |  |  |  |  |  |  | 
          
            | conference | 531 | tcp | chat |  |  |  |  |  |  |  |  | 
          
            | conference | 531 | udp | chat |  |  |  |  |  |  |  |  | 
          
            | netnews | 532 | tcp | readnews |  |  |  |  |  |  |  |  | 
          
            | netnews | 532 | udp | readnews |  |  |  |  |  |  |  |  | 
          
            | netwall | 533 | tcp | for emergency broadcasts | [Andreas_Heidemann] | [Andreas_Heidemann] |  |  |  |  |  |  | 
          
            | netwall | 533 | udp | for emergency broadcasts | [Andreas_Heidemann] | [Andreas_Heidemann] |  |  |  |  |  |  | 
          
            | windream | 534 | tcp | windream Admin | [Uwe_Honermann] | [Uwe_Honermann] |  |  |  |  |  |  | 
          
            | windream | 534 | udp | windream Admin | [Uwe_Honermann] | [Uwe_Honermann] |  |  |  |  |  |  | 
          
            | iiop | 535 | tcp | iiop | [Jeff_M_Michaud] | [Jeff_M_Michaud] |  |  |  |  |  |  | 
          
            | iiop | 535 | udp | iiop | [Jeff_M_Michaud] | [Jeff_M_Michaud] |  |  |  |  |  |  | 
          
            | opalis-rdv | 536 | tcp | opalis-rdv | [Laurent_Domenech] | [Laurent_Domenech] |  |  |  |  |  |  | 
          
            | opalis-rdv | 536 | udp | opalis-rdv | [Laurent_Domenech] | [Laurent_Domenech] |  |  |  |  |  |  | 
          
            | nmsp | 537 | tcp | Networked Media Streaming Protocol | [Paul_Santinelli_Jr] | [Paul_Santinelli_Jr] |  |  |  |  |  |  | 
          
            | nmsp | 537 | udp | Networked Media Streaming Protocol | [Paul_Santinelli_Jr] | [Paul_Santinelli_Jr] |  |  |  |  |  |  | 
          
            | gdomap | 538 | tcp | gdomap | [Richard_Frith_Macdon] | [Richard_Frith_Macdon] |  |  |  |  |  |  | 
          
            | gdomap | 538 | udp | gdomap | [Richard_Frith_Macdon] | [Richard_Frith_Macdon] |  |  |  |  |  |  | 
          
            | apertus-ldp | 539 | tcp | Apertus Technologies Load Determination |  |  |  |  |  |  |  |  | 
          
            | apertus-ldp | 539 | udp | Apertus Technologies Load Determination |  |  |  |  |  |  |  |  | 
          
            | uucp | 540 | tcp | uucpd |  |  |  |  |  |  |  |  | 
          
            | uucp | 540 | udp | uucpd |  |  |  |  |  |  |  |  | 
          
            | uucp-rlogin | 541 | tcp | uucp-rlogin | [Stuart_Lynne] | [Stuart_Lynne] |  |  |  |  |  |  | 
          
            | uucp-rlogin | 541 | udp | uucp-rlogin | [Stuart_Lynne] | [Stuart_Lynne] |  |  |  |  |  |  | 
          
            | commerce | 542 | tcp | commerce | [Randy_Epstein] | [Randy_Epstein] |  |  |  |  |  |  | 
          
            | commerce | 542 | udp | commerce | [Randy_Epstein] | [Randy_Epstein] |  |  |  |  |  |  | 
          
            | klogin | 543 | tcp |  |  |  |  |  |  |  |  |  | 
          
            | klogin | 543 | udp |  |  |  |  |  |  |  |  |  | 
          
            | kshell | 544 | tcp | krcmd |  |  |  |  |  |  |  |  | 
          
            | kshell | 544 | udp | krcmd |  |  |  |  |  |  |  |  | 
          
            | appleqtcsrvr | 545 | tcp | appleqtcsrvr | [Murali_Ranganathan] | [Murali_Ranganathan] |  |  |  |  |  |  | 
          
            | appleqtcsrvr | 545 | udp | appleqtcsrvr | [Murali_Ranganathan] | [Murali_Ranganathan] |  |  |  |  |  |  | 
          
            | dhcpv6-client | 546 | tcp | DHCPv6 Client |  |  |  |  |  |  |  |  | 
          
            | dhcpv6-client | 546 | udp | DHCPv6 Client | [IESG] | [IETF_Chair] |  | 2018-05-21 | [RFC-ietf-dhc-rfc8415bis-12] |  |  |  |