Socket number list
A record of service numbers assigned to public functions on the early network.
Postel, J., "Socket number list", RFC 433, DOI 10.17487/RFC0433, December 1972, <https://www.rfc-editor.org/info/rfc433>.
@misc{rfc433,
series = {Request for Comments},
number = 433,
howpublished = {RFC 433},
publisher = {RFC Editor},
doi = {10.17487/RFC0433},
url = {https://www.rfc-editor.org/info/rfc433},
author = {J. Postel},
title = {{Socket number list}},
pagetotal = 5,
year = 1972,
month = dec,
} RFC text
Network Working Group Jon Postel (UCLA-NMC)
Request for Comments: 433 Nancy Neigus (BBN)
NIC 13491 22 December 1972
Categories: Socket Numbers
References: 349
Socket Number List
The czar of socket numbers [Jon Postel] has established the
following assignments for socket numbers used for public
functions. Note that a socket number is a 40 bit quantity, the
first 8 bits being the host specification, the next 24 bits being
site specific, and the last 8 bits being user specified - these
last 8 bits are called the AEN [it stands for, cleverly enough,
Another Eightbit Number].
For the assignments here the value in the host field ranges
across all hosts (unless otherwise specified), the value in the
24 bit field is zero, and the AEN is indicated here.
General Assignments:
Sockets Assignment
0 - 63 Network Wide Standard Functions
64 - 127 Host Specific Functions
128 - 239 Reserved for Future Use
240 - 255 Any Experimental Function
Particular Assignments:
Socket Assignment
1 Telnet
3 File Transfer
5 Remote Job Entry
7 Echo
9 Discard
19 Character Generator [e.g. TTYTST]
65 Speech Data Base @ ll-tx-2 (74)
67 Datacomputer @ cca (31)
241 NCP Measurement
243 Survey Measurement
245 LINK
The specifications for the assigned functions can be found in the
documents listed here:
Telnet RFC 318
File Transfer RFC 354 & RFC 385
Remote Job Entry RFC 407
Echo RFC 347
Discard RFC 348
Character Generator RFC 429
Speech Data Base SUR 37
Datacomputer [Murray @ CCA]
NCP Measurment RFC 388
Survey Data [Kampe @ NMC]
LINK [Bressler @ BBN]
It has come to our attention that there are several hosts
performing useful public services on sockets which conflict with
the above scheme. We hope we can resolve this problem with a
minimum of disruption.
The following is a tabulation of socket numbers together with the
services offered. This listing is presented as an aid to network
users. If you know of a socket/function which has been left out
or an entry which should be corrected or deleted please contact:
Jon Postel
3804 Boelter Hall
Computer Science Department
University of California
Los Angeles, CA. 90024
Phone: (213) 825-2368
NIC Ident = JBP
or
Nancy Neigus
Bolt Beranek and Newman
50 Moulton Street
Cambridge, Mass. 02139
Phone: (617) 661-0100
NIC Ident = NJN
We will be pleased to include socket/function information for
other than "offical" sockets [e.g Tip News].
1 UCLA-NMC
1 Telnet
241 NCP Measurement
243 Survey Data
2 SRI-ARC
1 Telnet
3 File Transfer
5 Echo
7 CPYNET
9 SYSTAT
13 DATE-TIME
3 UCSB
1 Telnet
5 UCSB RJS [not ARPANET standard]
7 Echo
9 Discard
4 UTAH
1 Telnet
3 File Transfer
5 Echo
7 CPYNET
9 SYSTAT
13 DATE-TIME
5 NCC
6 MIT-Multics
1 Telnet
9 Harvard
1 Telnet
3 Sorry File Transfer
10 LL-67
1 Telnet
11 SAIL
1 Telnet
3 File Transfer
12 ILL-ANTS
13 CASE
1 Telnet
3 File Transfer
5 Echo
7 CPYNET
9 SYSTAT
13 DATE-TIME
14 CMU
1 Telnet
3 File Transfer
15 ILLIAC-TENEX
1 Telnet
3 File Transfer
5 Echo
7 CPYNET
9 SYSTAT
13 DATE-TIME
16 NASA-AMES
1 Telnet
3 File Transfer
5 Sorry Remote Job Entry
7 Echo
9 Discard
241 NCP Measurement
23 USC-44
31 CCA-TENEX
1 Telnet
3 File Transfer
5 Echo
9 SYSTAT
11 NETSTAT
35 UCSD
1 Telnet
65 UCLA-CCN
1 Telnet
7 Echo
9 Discard
11 NETPJS [EBCDIC]
13 NETRJS [ASCII]
15 NETRJS [TTY]
66 SRI-AI
1 Telnet
3 DATE-TIME
5 Echo
7 CPYNET
9 SYSTAT
11 Sorry NETSTAT
69 BBN-TENEX (a)
1 Telnet
3 File Transfer
5 Echo
7 CPYNET
9 SYSTAT
13 DATE-TIME
15 NETSTAT
17 Oneliners
3604505 = x'370019' = o'15600031' TIP News
70 MIT-DMCG
1 Telnet
3 File Transfer
7 Network Status
9 Discard
74 LL-TX-2
1 Telnet
78 CMU-alt
1 Telnet
3 File Transfer
86 ISI-TENEX
1 Telnet
3 File Transfer
5 Echo
7 CPYNET
9 SYSTAT
13 DATE-TIME
133 BBN-TENEXB
1 Telnet
3 File Transfer
5 Echo
7 CPYNET
9 SYSTAT
13 DATE-TIME
15 NETSTAT
17 Oneliners
134 MIT-AI
1 Telnet
3 File Transfer
198 MIT-Mathlab
1 Telnet
3 File Transfer
Following hosts not tested
7 RAND
8 SDC-ADEPT
19 NBS-ANTS
138 LL-TSP
[ This RFC was put into machine readable form for entry ]
[ into the online RFC archives by James Carlson 11/98 ]
ISO Plain Language
On this page
§1How a Socket Number Is Divided
The RFC describes a socket number as a 40-bit quantity. Its first 8 bits specify the host, the next 24 bits are site-specific, and the final 8 bits are the AEN, or Another Eightbit Number. In these assignments, the host field applies across hosts unless noted, and the 24-bit field is zero.
A socket number combines a host identifier with a number for a particular function. This list sets the site-specific part to zero and gives the function number in the AEN field.
§2Ranges and Named Functions
The general ranges are 0–63 for network-wide standard functions, 64–127 for host-specific functions, 128–239 reserved for future use, and 240–255 for experimental functions. Named assignments include Telnet at 1, File Transfer at 3, Remote Job Entry at 5, Echo at 7, Discard at 9, and Character Generator at 19.
The document also points to specifications for assigned functions. It notes that some hosts were already offering useful public services on numbers that conflicted with the scheme.
The number range indicates whether a function is standard across the network, specific to one host, reserved, or experimental. The RFC also gives numbers to named services such as Telnet and File Transfer.
§3Services Reported by Hosts
A host-by-host list records socket numbers and the services reported at each site. The RFC presents the list as an aid to network users and invites corrections or missing entries, including information about services that were not considered official.
The host list shows which services had been reported at each computer. The authors invite readers to send corrections and additions.
§4Status of This List
The unit metadata records RFC 503 as the document that replaced RFC 433. The assignments and host listings here therefore describe the earlier list, not a current service directory.
This is an earlier version of the socket list. RFC 503 later replaced it.