Status of Network Hosts
A December 1971 report of ARPANET host tests and excluded hosts
Westheimer, E., "Status of Network Hosts", RFC 287, DOI 10.17487/RFC0287, December 1971, <https://www.rfc-editor.org/info/rfc287>.
@misc{rfc287,
series = {Request for Comments},
number = 287,
howpublished = {RFC 287},
publisher = {RFC Editor},
doi = {10.17487/RFC0287},
url = {https://www.rfc-editor.org/info/rfc287},
author = {E. Westheimer},
title = {{Status of Network Hosts}},
pagetotal = 5,
year = 1971,
month = dec,
} RFC text
Network Working Group Ellen Westheimer
Request for Comments: #287 BBN
NIC: #8273 22 December 1971
Categories: F, G.3
Updates: RFC #267
Obsoletes: None
Status of Network Hosts
This RFC reports on the status of most Network Hosts from
December 6 to December 18. Due to hardware debugging, the BBN
prototype Terminal IMP (Network Address 158) was unavailable for most
of the two weeks from November 22 to December 6. There was, therefore,
no Host status reports for that period.
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
------- ---- --------
133 BBN PDP-10 (B)
71 Rand PDP-10
13 Case PDP-10
15 Ames/(Paoli) ILLIAC/(B6500)
16 Ames IBM-360/67
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
Address Site Computer
------- ---- --------
7 Rand IBM-360/65
73 Harvard PDP-1
12 Illinois PDP-11
19 NBS PDP-11
The NBS Terminal IMP (Network Address 147) was installed in
Washington at the beginning of December.
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.
NETWORK
ADDRESS SITE COMPUTER DAY, DATE AND TIME (EASTERN)
------- ---- -------- ----------------------------
M Tu W Th F
12/6 12/7 12/8 12/9 12/10
1300 1700 1300 1300 1630
1 UCLA SIGMA-7 D O O H T
*65 UCLA IBM-360/91 H H D H H
2 SRI (NIC) PDP-10 D T D D D
66 SRI (AI) PDP-10 D D D D D
3 UCSB IBM-360/75 O D O R D
4 UTAH PDP-10 T D D D T
69 BBN PDP-10 D D D D T
6 MIT (Multics) H-645 O O O T O
70 MIT (DM) PDP-10 O O D D O
8 SDC IBM-360/67 #D #D #D #D #D
9 HARVARD PDP-10 D T D O D
10 LINCOLN LAB IBM-360/67 D D D D H
74 LINCOLN LAB TX2 D D D D D
11 STANFORD PDP-10 D D D D D
14 CARNAGIE PDP-10 D D O 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.)
NETWORK
ADDRESS SITE COMPUTER DAY, DATE AND TIME (EASTERN)
------- ---- -------- ----------------------------
M Tu W Th F
12/13 12/14 12/15 12/16 12/17
1300 1700 1700 1600 1400
1000 1400 1400 1300 1100
1 UCLA SIGMA-7 D #D D O O
*65 UCLA IBM-360/91 O #D D O O
2 SRI (NIC) PDP-10 D D D T O
66 SRI (AI) PDP-10 D D D D D
3 UCSB IBM-360/75 T O D O D
4 UTAH PDP-10 D D D D D
69 BBN PDP-10 T H H O T
6 MIT (Multics) H-645 O H O D D
70 MIT (DM) PDP-10 D O D O O
8 SDC IBM-360/67 #D #D #D #D #D
9 HARVARD PDP-10 O D O D T
10 LINCOLN LAB IBM-360/67 H D H H H
74 LINCOLN LAB TX2 D D D H D
11 STANFORD PDP-10 D D D D D
14 CARNAGIE PDP-10 D D D D D
*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 NETJRS. We are assuming that initial connection to the NETRJS
logger indicates that NETJRS is also functioning.
# These sites advertise that they may not have their systems available
at these times.
"STATUS OR
NETWORK PREDICTIONS"
ADDRESS SITE COMPUTER STATUS OR PREDICTION OBTAINED FROM
------- ---- -------- -------------------- -------------
1 UCLA SIGMA-7 Server Jon Postel
65 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
*133 BBN (TENEX-B) PDP-10 Server (Experimental) 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
10 LINCOLN IBM-360/67 "Soon" Joel Winnet
74 LINCOLN TX2 "Soon" 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/(PAOLI) ILLIAC/
(B6500) September '62 John McConnel
*16 AMES IBM-360/67 Januray '72 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
(Prototype) User only
*Host not included in daily testing.
[ This RFC was put into machine readable form for entry ]
[ into the online RFC archives by Daniel Lang 4/97]
ISO Plain Language
On this page
§1Reporting Period and Exclusions
The report covers most Network Hosts from December 6 through December 18. The BBN prototype Terminal IMP was unavailable for much of the preceding period, from November 22 to December 6, because of hardware debugging; the report says there was no host status report then.
Hosts excluded from daily tests fall into two groups: those not expected to operate regularly as servers for at least two weeks, and hosts intended only as users. The Network Control Center computer is also listed as used solely for gathering network statistics.
BBN reports on the listed period and explains why no report covered the prior interval. Some hosts were omitted because they were not expected to serve other sites or were user-only systems.
§2Daily Status Codes
The daily tables show a result for each host on each listed test day. D means dead or inaccessible from the BBN Terminal IMP; H means a connection opened but immediately closed or stopped responding; O means the host opened a connection and was accessible to users.
R means the destination returned a close to the initial request. T means the destination did not complete the Initial Connection Protocol and open a connection within 60 seconds. Marks identify sites that warned they might not be available at those times.
The report uses letters to describe each test. One code means a host was accessible; the others show different kinds of failure or partial response.
§3Host Predictions and Replacement
A separate table gives host status or predictions supplied by operators, including labels such as Server, User only and Soon. It names the person who supplied each entry.
The unit metadata records RFC 288 as the document that later obsoleted RFC 287.
Operators also reported whether a host was a server, a user-only system, or expected to become a server. RFC 288 later replaced this report.