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ARPANET Outage Data Breach

3x12 - ARPANET Continue

Appeared inAletheia

Mentioned in2πR

DateOctober 27, 1980

LocationLassiter, Iowa, U.S.

Caused byHarold Finch

If they don't want you to get inside, they ought to build it better.

— Harold Finch, 1969 (“Lethe”)

The ARPANET Outage Data Breach occurred on October 27, 1980 and lasted four hours. 73 nodes were affected, leading to 2,153 breached files. The U.S. Department of Defense conducted an investigation under tracking ID I-3557 that remains open as no culprit has been identified yet.


Funded by the U.S. Department of Defense, the Advanced Research Projects Agency Network (ARPANET) was built to connect universities and research laboratories engaged in defense-related projects. After several attempts to link various nodes, ARPANET went online in 1969 with a transmission from the University of California, Los Angeles to the Stanford Research Institute's Augmentation Research Center, the University of California, Santa Barbara and the University of Utah. ARPANET formally decommissioned on February 28, 1990, but it is widely regarded as the birthplace of the modern internet.

The breach was committed by Harold Finch during his efforts to build a prototype of the Machine, as a means to acquire more computing power for his device, Finch used a "Phone Phreak" to hack ARPANET. He is later pursued by the government for treason, apparently for hacking ARPANET. (“Aletheia”)


Chris Beckner, a computer science teacher, talks about a hacker who got into the ARPANET and opened it up to the world without ever getting caught. Later, Finch tells Caleb Phipps about how a kid with a homemade computer turned the ARPANET inside out during the Cold War. When Caleb asks how he knew that the ARPANET hacker had a homemade computer, Finch says that he must have heard it somewhere. (“2πR”)


Harold's Code

  • The code is Fortran, from Example F Program—Big Integers.[1]

function big_eq_int (b, i)
result (bi)

type (big_integer), intent

(in) : : b

integer, intent (in) : : i
logical : : bi
integer : : i0, i1
i0 = modulo (i, base)
i1 = i / base
bi = b % digit (0) ==

i0 .and. & b % digit (1) ==
i1 .and. &
all (b % digit (2 :
or_of_digits) == 0)

and function big_eq_int


  • It is implied Finch is wanted for a second act of treason, as he is stated to have been wanted for treason since 1974. (“The Day the World Went Away”)