Network host status
A BBN snapshot of ARPANET host availability 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]
ISO Plain Language
On this page
§1The Reporting Period
This report covers the status of most Network Hosts from December 20 to December 30. BBN did not test on December 24 or December 31 because of its Christmas and New Year's observances. The report notes that the Lincoln Labs TX2, Network Address 112, became a server during this period.
The report is a dated operational snapshot. It includes both test results and status predictions supplied by people at the listed sites.
The report shows which hosts responded during the listed test period. It also notes that the Lincoln Labs TX2 began acting as a server.
§2Hosts Excluded from Daily Tests
The report excludes hosts not expected to function regularly as servers for at least two weeks. It also excludes hosts intended to be users only. These include Terminal IMPs, the Network Control Center computer used to gather network statistics, and several site computers listed in the RFC.
The BBN Terminal IMP at Network Address 158 is a prototype. It is often disconnected because its programs are being refined and debugged. A star in the tables marks hosts not included in daily testing.
Some hosts were left out because they were not expected to provide regular service or were intended only to use other hosts. The report marks these exclusions in its tables.
§3Test Results and Their Meaning
One table lists each host's network address, site, computer, reported status or prediction, and the person who supplied it. Other tables record tests by date and time. A hash mark means the site had warned that its system might not be available at that time.
The result codes distinguish an open and accessible host, a dead or inaccessible host, a connection that opened only briefly, a refusal, and a timeout. A timeout means the host did not complete the Initial Connection Protocol (ICP) and open a connection within 60 seconds. The BBN Terminal IMP could not test the UCLA IBM-360/91's NETRJS service, so the report treated a connection to its logger as evidence that the service worked.
The tables use short codes to show what happened during each test. A timeout means the host did not finish the connection process within 60 seconds.
- DDead — Host was dead or inaccessible from the BBN Terminal IMP.
- HHalf 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.