Traffic statistics (November 1973)
A snapshot of ARPANET traffic volume across all hosts in November 1973
McKenzie, A.M., "Traffic statistics (November 1973)", RFC 601, DOI 10.17487/RFC0601, December 1973, <https://www.rfc-editor.org/info/rfc601>.
@misc{rfc601,
series = {Request for Comments},
number = 601,
howpublished = {RFC 601},
publisher = {RFC Editor},
doi = {10.17487/RFC0601},
url = {https://www.rfc-editor.org/info/rfc601},
author = {A.M. McKenzie},
title = {{Traffic statistics (November 1973)}},
pagetotal = 5,
year = 1973,
month = dec,
} RFC text
Network Working Group A. McKenzie
RFC # 601 BBN-NET
NIC # 20905 14 December 1973
Updates: RFC # 586
Traffic Statistics (November 1973)
Attached are the Host traffic statistics for the month of November 1973.
AAM/jm
Attach.
HOST THROUGHPUT SUMMARY
(PACKETS OUTPUT)
NOVEMBER 1973
INTER- INTRA- AVG. DAILY
NODE NODE TOTAL INTERNODE DAYS
UCLA HOST 0 241273 30480 271753
UCLA HOST 1 1536918 56526 1593444
UCLA HOST 2 26253 4954 31207
-------- -------- --------
1804444 91960 1896404 60148 30
SRI HOST 0 6519907 208536 6728443
SRI HOST 1 574488 162319 736807
-------- -------- --------
7094395 370855 7465250 236480 30
UCSB HOST 0 2549879 76826 2626705
UCSB HOST 1 313615 2751 316366
-------- -------- --------
2863494 79577 2943071 95450 30
UTAH HOST 0 1304159 203988 1508147
UTAH HOST 2 87741 187693 275434
-------- -------- --------
1391900 391681 1783581 46397 30
BBN HOST 0 10 26935 26945
BBN HOST 1 5933376 336528 6269904
BBN HOST 2 52098 55531 107629
BBN HOST 3 247706 17072 264778
-------- -------- --------
6233190 436066 6669256 207773 30
M-MAC HOST 0 405008 78836 483844
M-MAC HOST 1 1139680 248773 1388453
M-MAC HOST 2 1071807 755648 1827455
M-MAC HOST 3 855130 755184 1610314
-------- -------- --------
3471625 1838441 5310066 115721 30
RAND HOST 0 1626780 36341 1663121 54226 30
SDC HAD NO TRAFFIC 30
HARV HOST O 1363275 1084755 2448030
HARV HOST 1 969135 1294673 2263808
-------- -------- --------
2332410 2379428 4711838 77747 30
LINC HOST 0 28913 15009 43922
LINC HOST 1 45842 19861 65703
LINC HOST 2 4772 19698 24470
-------- -------- --------
79527 54568 134095 2651 30
STAN HOST 0 1812959 6692 1819651 60432 30
ILL HOST 0 1944572 240 1944812
ILL HOST 1 34288 257 34545
ILL HOST 2 163 5 168
-------- -------- --------
1979023 502 1979525 65967 30
CASE HOST 0 2569407 36272 2605679 85647 30
CARN HOST 0 979677 451688 1431365
CARN HOST 1 592226 494991 1087217
-------- -------- --------
1571903 946679 2518582 52397 30
AMES HOST 0 3550158 27201 3577359 118339 30
AMEST HOST 0 129967 19797 149764
AMEST HOST 2 5340672 37480 5378152
-------- -------- --------
5470639 57277 5527916 182355 30
MITRE HOST 2 2939264 218 29394282 97975 30
ROME HOST 2 1248304 196 1248500 41610 30
NBS HOST 2 2343085 27095 2370180 78103 30
ETAC HOST 0 1150626 10 1150636 38354 30
LLL HOST 0 163639 319 163958 5455 30
ISI HOST 1 11056000 145966 11201970 368533 30
USC HOST 0 165622 2291501 2457123
USC HOST 2 4178240 2168615 6346855
-------- -------- --------
4343862 4460116 8803978 144795 30
GWC HOST 2 3671911 56 3671967 122397 30
DOCB HOST 2 127876 2706 130582 4263 30
SDAC HOST 0 35717 0 35717
SDAC HOST 2 807398 36 807434
-------- -------- --------
843115 36 843151 28104 30
BELV HOST 0 4895 126 5021
BELV HOST 1 1162 51 1213
-------- -------- --------
6057 177 6234 202 30
ARPA HOST 0 29820 387317 417137
ARPA HOST 2 1976769 382267 2359036
-------- -------- --------
2006589 769584 2776173 66886 30
ABER HAD NO TRAFFIC 30
BBN T HOST 2 2240310 674 2240975 74677 30
CCA HOST 0 781493 834094 1615587
CCA HOST 2 2956749 451325 3408074
-------- -------- --------
3738242 1285419 5023661 124608 30
XEROX HOST 0 2056013 415370 2471383
XEROX HOST 1 0 9736768 9736768
-------- -------- --------
2056013 10152140 12208150 68534 30
FNWC HOST 0 33 986 1019
FNWC HOST 2 63856 35 63891
-------- -------- --------
63889 1021 64910 2130 30
LBL HAD NO TRAFFIC 30
UCSD HOST 0 653614 46348 699962 21787 30
HAW T HOST 0 1 1398 1399
HAW T HOST 2 768335 109011 877346
HAW T HOST 3 6686 12 6698
-------- -------- --------
775022 110421 885443 25834 30
RML HOST 2 532132 173 532305 17738 30
NCC-T HOST 0 126 12559 12685
NCC-T HOST 2 540407 18493 558900
NCC-T HOST 3 16999 54771 71770
-------- -------- --------
557532 85823 643355 46461 12
NORSR HOST 2 146110 20 146130 4870 30
ULOND HOST 0 36630 25629 62259
ULOND HOST 2 527040 69483 596523
-------- -------- --------
563670 95112 658782 18789 30
TYMSH HOST 0 1484 23245 24729
TYMSH HOST 2 49015 18 49033
-------- -------- --------
50499 23263 73762 1683 30
M-IPC HOST 0 145 11083 11228 5 30
MOFF HAD NO TRAFFIC 30
RUTGS HOST 2 99059 117 99176 6191 16
WRPAT HOST 2 85688 41 85729 2856 30
----------------------------------------
TOTAL 85314100 23971670
DAILY AVERAGE 2843803 799056
AVERAGE PER 64730 18188
NODE-DAY
PACKETS/MESSAGES (INTERNODE) 1.08
[ This RFC was put into machine readable form for entry ]
[ into the online RFC archives by Alex McKenzie with ]
[ support from GTE, formerly BBN Corp. 1/2000 ]
AI ELI5
On this page
§1ARPANET Traffic Statistics
This RFC publishes the first public record of ARPANET traffic volume for a single month: November 1973. It tabulates, for each connected host, how many packets it transmitted, split between traffic destined for other hosts (inter-node) and traffic within the same node (intra-node). Each host typically operated multiple machines, so the data is broken down by individual host identity. The report includes daily averages, allowing readers to understand traffic patterns across a month.
This is a monthly count of how many data packets each computer on the ARPANET sent, listed so people can see which sites were busiest.
§2Traffic Distribution
The data reveals stark differences in traffic volume. ISI Host 1 was by far the heaviest user, sending 11.2 million inter-node packets. Other heavy users included Ames Host 0 (3.5 million), XEROX Host 1 (9.7 million intra-node but none inter-node), and several others in the millions. The lightest sites, like BELV, sent only a few thousand packets. In total, the network carried approximately 85 million inter-node packets and 24 million intra-node packets in November, for an average of 2.8 million packets per day. The ratio of total packets to messages was 1.08, indicating that most messages arrived intact in a single packet.
Some computers sent hundreds of millions of packets (the big research centers), others sent thousands (the small sites). The network as a whole handled about 85 million inter-node packets in the month.
§3Significance
This monthly traffic summary establishes a baseline for ARPANET operations in late 1973, about four years after the network's inception. The data shows a mature, active network with substantial traffic from research institutions, particularly ISI, Ames, and Stanford. The relatively low ratio of packets to messages (1.08) indicates the network was working well—most messages needed just one packet. This RFC begins a tradition of monthly traffic reporting that would inform network planning and operations decisions for years.
By 1973, ARPANET was healthy and busy, with lots of research centers actively using it. This count showed the network was ready for more growth.