Network Host Status
A 1972 status report on which ARPANET hosts were up, and which were left out of daily testing.
Westheimer, E., "Network Host Status", RFC 326, DOI 10.17487/RFC0326, April 1972, <https://www.rfc-editor.org/info/rfc326>.
@misc{rfc326,
series = {Request for Comments},
number = 326,
howpublished = {RFC 326},
publisher = {RFC Editor},
doi = {10.17487/RFC0326},
url = {https://www.rfc-editor.org/info/rfc326},
author = {E. Westheimer},
title = {{Network Host Status}},
pagetotal = 4,
year = 1972,
month = apr,
} RFC text
Network Working Group Ellen Westheimer
NIC # 9633 BBN
RFC # 326 3 April 1972
Categories: F, G.3
Updates: RFC #319
Obsoletes: None
NETWORK HOST STATUS
This RFC reports on the status of most Network Hosts from
March 13 to March 24. During this period the SRI-AI computer
became a server.
Several Hosts are currently excluded from 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) on a regular basis for at
least two weeks. Included here are:
Network
Address Site Computer
------- ---- --------
134 MIT-AI PDP-10
13 Case PDP-10
2) Hosts which are currently intended to be users only. Included here
are the Terminal IMPs, which are presently in the Network (AMES,
MITRE, NBS, ETAC, 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
19 NBS PDP-11
The tables on the next two pages summarize the 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.
"STATUS OR
SITE PREDICTIONS"
ADDRESS SITE COMPUTER STATUS OR PREDICTION OBTAINED FROM
------- ---- -------- -------------------- -------------
1 UCLA SIGMA-7 Server #Limited Jon Postel
65 UCLA IBM-360/91 NETRJS now Bob Braden
(Telnet in April)
2 SRI(NIC) PDP-10 Server John Melvin
66 SRI(AI) PDP-10 Server Len Chaiten
3 UCSB IBM-360/75 Server Jim White
4 UTAH PDP-10 Server Barry Wessler
*5 BBN(NCC) DDP-516 Never Alex McKenzie
69 BBN(TENEX-A) PDP-10 Server Dan Murphy
*133 BBN(TENEX-B) PDP-10 Server (Exper.) Dan Murphy
*158 BBN TIP User Only
(Prototype)
6 MIT(Multics) H-645 Server Mike Padlipsky
70 MIT(DM) PDP-10 Sever Bob Bressler
*134 MIT(AI) PDP-10 User Now Jeff Rubin
*7 RAND IBM-360/65 User Only Eric Harslem
71 RAND PDP-10 Server Eric Harslem
*8 SDC IBM-360/155 Server Bob Long
9 HARVARD PDP-10 Server Bob Sundberg
*73 HARVARD PDP-1 User Only Bob Sundberg
10 LINCOLN IBM-360/67 "Soon" Joel Winett
74 LINCOLN TX-2 Server Will Kantrowitz
11 STANFORD PDP-10 "Soon" Andy Moorer
*12 ILLINOIS PDP-11 User Only John Cravits
*13 CASE PDP-10 June Charles Rose
14 CARNEGIE PDP-10 "Soon" Hal VanZoeren
*15 AMES/(PAOLI) ILLIAC "Soon" John McConnell
(B6500)
16 AMES IBM-360/67 "Soon" Wayne Hathaway
*144 AMES TIP User Only
*145 MITRE TIP User Only
*19 NBS PDP-11 User Only Robert Rosenthal
*147 NBS TIP User Only
*148 ETAC TIP User Only
_________________
*Host not included in daily testing
#The NMC is a research site and would like
to have prior arrangement with each user.
SITE
NO. SITE DATE AND TIME (EASTERN)
---- ---- -----------------------
3/13 3/14 3/15 3/16 3/17 3/20 3/21 3/22 3/23 3/24
1530 1400 1530 1430 1730 1400 1300 1700 1700 1300
1 UCLA-NMC O O O O D O O O O O
65 UCLA-CNN O O O O O O O O O D
2 SRI-ARC #D D O O O D D D D T
66 SRI-AI D D D D O D D D D D
3 UCSB-MOD75 O O O O O O O O O D
4 UTAH-10 O D O O O O O O O O
69 BBN-TENEX O O O O D D D O O O
133 BBN-TENEXB #D #D #D #D #D #D #D #D #D #D
6 MIT-Multics D T D D D H D O O O
70 MIT-DMCG H O O O T O H O O H
71 RAND-CSG H H O O O O O O D T
8 SDC-ADEPT #D #D #D #D H #D #D #D D #D
9 HARVARD-10 O O O O O O D O O O
10 L.L.-360 H H H H H H H H D H
74 L.L.- TX-2 O O #D O O O O O O O
11 STANFORD-AI D D H D D D D D D D
14 CMU-10 D D D H H D H D O H
15 AMES-Illiac D D D D D D D D D D
16 AMES-67 D D D D D D 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.)
H = 1/2 Open (Destination Host opened a connection but then either
immediately closed it, or did not respond any further.)
O = Open (Destination Host opened a connection and was accessible to users.)
R = Refused (Destination Host returned a CLS to the initial RFC.)
T = Timed out (Destination Host did not complete the ICP and open a
connection within 60 seconds.)
________________
*The only service currently offered by the UCLA IBM-360/91 is a Network
Job Service (NETRJS), however, the BBN Terminal IMP is not equipped to
test NETRJS. We are assuming that initial connection to the NETRJS
logger 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 BBN Corp. under the ]
[ direction of Alex McKenzie. 12/96 ]
AI ELI5
On this page
§1Scope of the Report
The report covers the status of most Network Hosts from March 13 to March 24. During this period the SRI-AI computer became a server.
Some hosts were excluded from the daily testing. One group was not expected to function as servers on a regular basis for at least two weeks, including MIT-AI (address 134) and Case (address 13), both PDP-10s.
The report says which computers were checked every day and which were skipped, like roll call with a few kids marked as away.
§2Users-Only Hosts and Status Table
The second excluded group was hosts intended to be users only: the Terminal IMPs (AMES, MITRE, NBS, ETAC and BBN), the Network Control Center computer at address 5, which only gathers statistics, and four other hosts: Rand IBM-360/65, Harvard PDP-1, Illinois PDP-11 and NBS PDP-11.
A table lists each host by address, site and computer, with a status or prediction such as Server, User Only, Soon or June, and the person it was obtained from.
Some computers were only for people to sit at, not for helping others. The table says what each one was doing or when it would be ready.
§3Daily Test Results
A second table shows results for ten test times from 3/13 to 3/24, tested from the BBN Terminal IMP. Each cell is one letter: O Open, H half open (the host opened a connection then closed it or went silent), D Dead (dead or inaccessible), R Refused, and T Timed out (no completed ICP and open connection within 60 seconds).
The UCLA IBM-360/91 offers only a Network Job Service (NETRJS), which the Terminal IMP could not test, so a connection to the NETRJS logger was assumed to mean NETRJS worked.
Every day someone knocked on each computer's door. The letters say whether it answered, answered then went quiet, or never came to the door.
- OOpen — Host opened a connection and was accessible to users.
- H1/2 Open — Host opened a connection but then closed it, or did not respond further.
- DDead — Host dead or inaccessible from the BBN Terminal IMP.
- RRefused — Host returned a CLS to the initial RFC.
- TTimed out — ICP and connection not completed within 60 seconds.