Network host status
BBN's status report on which ARPANET hosts answered test connections from December 20 to 30, 1971.
Westheimer, E., "Network host status", RFC 288, DOI 10.17487/RFC0288, January 1972, <https://www.rfc-editor.org/info/rfc288>.
@misc{rfc288,
series = {Request for Comments},
number = 288,
howpublished = {RFC 288},
publisher = {RFC Editor},
doi = {10.17487/RFC0288},
url = {https://www.rfc-editor.org/info/rfc288},
author = {E. Westheimer},
title = {{Network host status}},
pagetotal = 4,
year = 1972,
month = jan,
} RFC text
Network Working Group E. Westheimer
Request for Comments: 288 BBN
NIC: 8274 January 6, 1972
Obsoletes: None
Updates: 287
NETWORK HOST STATUS
This RFC reports on the status of most Network Hosts from December 20
to December 30. (On December 24 and December 31 BBN celebrated
Christmas and New Year's Day respectively.)
During these two weeks the Lincoln Labs TX2 (Network Address 112)
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 SITE COMPUTER
ADDRESS
133 BBN PDP-10 (B)
15 Case PDP-10
13 Ames/(Paoli) ILLIAC/(B6500)
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 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 SITE COMPUTER
ADDRESS
7 Rand IBM-360/65
73 Harvard PDP-1
12 Illinois PDP-11
19 NBS PDP-11
* 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.
The tables on the next two pages summarize the Host status for this
period.
STATUS OR
NETWORK SITE COMPUTER STATUS OR PREDICTIONS
ADDRESS PREDICTION OBTAINED FROM
1 UCLA SIGMA-7 Server John Postel
65 UCLA IBM-360/91 Remote Job Service Bob Braden
(Telnet in April)
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-A) PDP-10 Server Dan Murphy
*133 BBN(TENEX-B) PDP-10 Server(Exper.) 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 SOON 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
10 LINCOLN IBM-360/67 SOON Joel Winnet
74 LINCOLN TX-2 Server Tom Barkalow
11 STANFORD PDP-10 SOON Andy Moorer
*12 ILLINOIS PDP-11 User only John Cravits
*13 CASE PDP-10 March Charles Rose
14 CARNEGIE PDP-10 SOON Hal VanZoeren
5 AMES/(PAOLI) ILLIAC September 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
*158 BBN TIP User only
(Prototype)
* Host not included in daily testing.
ADDRESS SITE COMPUTER DATE AND TIME (EASTERN)
NETWORK 12/20 12/21 12/22 12/23
1700 1200 1400 1700
1 UCLA SIGMA-7 O #D O O
65* UCLA IBM-360/91 O O D D
2 SRI(NIC) PDP-10 D O D D
66 SRI(AI) PDP-10 D D D D
3 UCSB IBM-360/75 T D D T
4 UTAH PDP-10 O O D D
69 BBN PDP-10 H O D O
6 MIT(Multics) H-645 D D D T
70 MIT(DM) PDP-10 O O H O
71 RAND PDP-10 D D D D
8 SDC IBM-360/67 #D #D #D #D
9 HARVARD PDP-10 D T D D
10 LINCOLN LAB IBM-360/67 H H H D
74 LINCOLN LAB TX2 H H #D T
11 STANFORD PDP-10 D D D D
14 CARNEGIE PDP-10 D D D D
16 AMES IBM-360/67 D D D D
ADDRESS SITE COMPUTER DATE AND TIME (EASTERN)
NETWORK 12/27 12/28 12/29 12/30
1730 1300 1600 1400
1 UCLA SIGMA-7 T #D O O
65* UCLA IBM-360/91 O O O O
2 SRI(NIC) PDP-10 D D D D
66 SRI(AI) PDP-10 D D D O
3 UCSB IBM-360/75 D D D D
4 UTAH PDP-10 D D D D
69 BBN PDP-10 O O O H
6 MIT(Multics) H-645 O O O O
70 MIT(DM) PDP-10 O D O D
71 RAND PDP-10 D D D D
8 SDC IBM-360/67 H #D #D #D
9 HARVARD PDP-10 T T D T
10 LINCOLN LAB IBM-360/67 D H T T
74 LINCOLN LAB TX2 D D #D H
11 STANFORD PDP-10 D D D D
14 CARNEGIE PDP-10 D D D D
16 AMES IBM-360/67 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 second)
* 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 indicated the 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 Kelly Tardif, Viag�nie 10/99]
AI ELI5
On this page
§1What the Report Covers
This RFC reports on the status of most network hosts from December 20 to December 30 (1971, per the RFC's January 1972 date). BBN celebrated Christmas and New Year's Day on December 24 and December 31, respectively. The report notes that the Lincoln Labs TX2 (Network Address 112) became a server during these two weeks.
It is a holiday-time report card for the network's computers.
§2Hosts Left Out of Daily Testing
Some hosts were excluded from daily testing in two categories. The first is hosts not expected to function as servers (available to other sites) on a regular basis for at least two weeks: addresses 133 (BBN PDP-10 B), 15 (Case PDP-10) and 13 (Ames/Paoli ILLIAC/B6500).
The second is hosts intended to be users only. These include the Terminal IMPs then on the network (AMES, MITRE, NBS and BBN), the Network Control Center computer (address 5), which only gathers statistics, and the Rand IBM-360/65, Harvard PDP-1, Illinois PDP-11 and NBS PDP-11. The BBN Terminal IMP (address 158) is a prototype that is often disconnected while its programs are refined and debugged.
Some computers were not tested because they only visit other computers and never serve anyone, or were not expected to be ready.
§3The Status Tables and Codes
One table lists each host's address, site, computer, status or prediction (such as Server, SOON, User only, or a month), and who supplied the prediction. Two more tables give the test result for each host on each test date, using the one-letter codes in the legend. A hash mark before a result means the site advertised that its system might not be available then.
A host counted as timed out (T) if it did not complete the ICP and open a connection within 60 seconds. The UCLA IBM-360/91 offered only a Network Job Service (NETRJS), which the BBN Terminal IMP could not test, so a successful initial connection to the NETRJS logger was assumed to mean NETRJS was working.
Each computer gets a letter for each day: open, dead, half-open, refused or too slow.
- DDead — Host dead or inaccessible from the BBN Terminal IMP.
- H1/2 Open — Host opened a connection, then closed it or stopped responding.
- OOpen — Host opened a connection and was accessible to users.
- RRefused — Host returned a CLS to the initial RFC.
- TTimed out — Host did not complete the ICP and open a connection within 60 seconds.