Network Host Status
ARPANET host status for November 8-19, 1971, noting new users and servers.
Westheimer, E., "Network Host Status", RFC 267, DOI 10.17487/RFC0267, November 1971, <https://www.rfc-editor.org/info/rfc267>.
@misc{rfc267,
series = {Request for Comments},
number = 267,
howpublished = {RFC 267},
publisher = {RFC Editor},
doi = {10.17487/RFC0267},
url = {https://www.rfc-editor.org/info/rfc267},
author = {E. Westheimer},
title = {{Network Host Status}},
pagetotal = 4,
year = 1971,
month = nov,
} RFC text
Network Working Group Ellen Westheimer
RFC #267 BBN
NIC #7815 22 November 1971
Categories: F, G.3
Updates: RFC #266
Obsoletes None
This RFC reports on the status of most Network Hosts from November
8 to November 19. On November 18, however, the BBN prototype Terminal
IMP (Network Address 158) was inaccessible due to hardware debugging.
Several Hosts are currently excluded fron the daily testing.
These Hosts fall into two categories:
1) Hosts which are not expected to be functioning on
the Network as servers (available for use from
other sites) for at least two weeks. Included here
are:
Network
Address Site Computer
71 Rand PDP-10
74 Lincoln TX2
13 Case PDP-10
14 Carnegie PDP-10
15 Ames B6500
16 Ames IBM-360/67
2) Hosts which are curently intended to be users only.
Included here are the Terminal IMPs, which are
presently in the Network (AMES, MITRE, and BBN*).
This category also includes the Network Control
Center Computer (Network Address 5) which is used
solely for gathering statistics from the Network.
Finally, included among these Hosts are the following:
Network
Address Site Computer
7 Rand IBM-360/65
73 Harvard PDP-1
12 Illinois PDP-11
During these two weeks the Lincoln Labs TX2 Hosts became a Network
User. The SDC IBM 360/67 is now a server.
The tables on the next two pages summarize the information on Host
status for this period.
* The BBN Terminal IMP (Network Address 158) is a prototype and
as such is frequently not connected to the Network, but being
used to refine and debug the Terminal IMP programs.
NETWORK STATUS or STATUS or
ADDRESS SITE COMPUTER PREDUCTION PREDUCTION
OBTAINED FROM
1 UCLA SIGMA-7 Server Jon Postel
5 UCLA IBM-360/91 Remote Job Service
now, Telnet in
April Bob Braden
2 SRI
(NIC) PDP-10 Server John Melvin
66 SRI
(AI) PDP-10 "Soon" Len Chaiten
3 UCSB IBM-360/75 Server Jim White
4 UTAH PDP-10 "Soon" Barry Wessler
*5 BBN
(NCC) DDP-516 Never Alex McKenzie
69 BBN
(TENEX) PDP-10 Server Dan Murphy
6 MIT
(Multics) H-645 Server Mike Padlipsky
70 MIT
(DM) PDP-10 Server Bob Bressler
*7 RAND IBM-360/65 User only Eric Harslem
*71 RAND PDP-10 January '72 Eric Harslem
8 SDC IBM-360/67 Server Bob Long
9 HARVARD PDP-10 Server Bob Sundberg
*73 HARVARD PDP-1 User only Bob Sundberg
20 LINCOLN IBM-360/67 "Soon" Joel Winnet
*74 LINCOLN TX2 December Tom Barkalow
11 STANFORD PDP-10 "Soon" Andy Moorer
*12 ILLINOIS PDP-11 User only John Cravits
*13 CASE PDP-10 March '72 Charles Rose
*14 CARNEGIE PDP-10 January '72 Hal vanZoeren
*15 AMES B6500 September '72 John McConnel
*16 AMES IBM-360/67 January '72 Wayne Hathaway
*144 AMES TIP User only
*145 MITRE TIP User only
*158 BBN TIP User only
(Proto-type)
* host not included in daily testing.
NETWORK
ADDRESS SITE COMPUTER DAY, DATE and TIME (Eastern)
M Tu W Th F
11/8 11/9 11/10 11/11 11/12
1 UCLA SIGMA-7 O D O O O
*65 UCLA IBM-360/91 O D O D O
2 SRI (NIC) PDP-10 O O O O T
66 SRI (AI) PDP-10 D D D D D
3 UCSB IBM-360/75 O T O O D
4 UTAH PDP-10 D D H D D
69 BBN (TENEX) PDP-10 H O O O O
6 MIT (Mulics) H-645 D D D O O
70 MIT (DM) PDP-10 O H T D O
8 SDC IBM-360/67 #D #D #D #D #D
9 HARVARD PDP-10 D D D D T
10 LINCOLN IBM-360/67 H H H H D
11 STANFORD PDP-10 D T D D D
M Tu W F
11/15 11/16 11/17 11/19
1 UCLA SIGMA-7 O O O O
*65 UCLA IBM-360/91 O O D O
2 SRI (NIC) PDP-10 T T O O
66 SRI (AI) PDP-10 D D D D
3 UCSB IBM-360/75 O O O O
4 UTAH PDP-10 D D D D
69 BBN (TENEX) PDP-10 O D O O
6 MIT (Mulics) H-645 T D O H
70 MIT (DM) PDP-10 O O O D
8 SDC IBM-360/67 #D #D #D #D
9 HARVARD PDP-10 T D D T
10 LINCOLN IBM-360/67 D H D D
11 STANFORD PDP-10 D D D D
where
D = Dead (Destination Host either dead or inaccessible [due to
network partitioning or local IMP failure] from the BBN
Terminal IMP.)
R = Refused (Destination Host returned a CLS to the initial RFC.)
T = Timed out (Destination Host did not respond in any way to the
initial RFC, although not dead.)
H = 1/2 Open (Destination Host opened a connection but then either
immediately closed it, or did not respond further.)
O = Open (Destination Host opened a connection and was accessible to
users.)
* The UCLA IBM-360/91 currently has Remote Job Service (NETRJS),
but has not implemented a full server Telnet System. The BBN
Terminal IMP is not equipped to test NETRJS; however, we are
assuming that receipt of the UCLA explanatory message indicates
that NETRJS is also functioning.
# These sites advertise that they may not have their system
available at these times.
[ This RFC was put into machine readable form for entry ]
[ into the online RFC archives by Simone Demmel 1/98 ]
AI ELI5
On this page
§1Introduction and Exclusions
RFC 267 reports on ARPANET host status from November 8 to November 19, 1971. On November 18 the BBN Terminal IMP was offline for hardware debugging. The report lists hosts excluded from daily testing in two categories: those not expected to be servers for at least two weeks (Rand PDP-10, Lincoln TX2, Case, Carnegie, Ames B6500 and IBM-360), and user-only hosts (Terminal IMPs and the Network Control Center). During this period, Lincoln's TX2 became a network user and SDC's IBM-360 became a server.
A report from mid-November showed which computers were tested, which ones were skipped, and noted that one computer changed from being tested to being left alone.
§2Daily Test Results
Two tables summarize host status for November 8-12 and November 15-19 (November 18 was excluded due to Terminal IMP downtime). Tests used status codes where O meant open, D meant dead, T meant timeout, H meant half-open, and R meant refused. Some sites advertised unavailable times. UCLA's IBM-360 is now explicitly noted to provide Remote Job Service only, without a Telnet server.
Tables showed each day's test results for 12 hosts, using the same letter codes to mark how each computer responded.
§3Host Predictions and Server Status
The report includes host status predictions from operators, showing expected dates when hosts would become servers (for example, Case predicted March 1972, Carnegie predicted January 1972). Most major hosts like UCLA, SRI NIC, UCSB, and MIT Multics were servers or soon would be. SDC was now confirmed as a server after this period. Some hosts like Stanford and Illinois remained user-only or had uncertain status.
Site operators said when their computers would be ready to help others, and the test results showed which ones were already working.