---
created_at: '2018-01-14T21:22:07.000Z'
title: Parasitic Computing (2001)
url: https://www.nature.com/articles/35091039
author: dedalus
points: 76
story_text: 
comment_text: 
num_comments: 25
story_id: 
story_title: 
story_url: 
parent_id: 
created_at_i: 1515964927
_tags:
- story
- author_dedalus
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objectID: '16146553'
year: 2001

---
Reliable communication on the Internet is guaranteed by a standard set
of protocols, used by all
computers[1](/articles/35091039#ref1 "Peterson, L. L. & Davie, B. S. Computer Networks, A Systems Approach 2nd edn (Morgan Kaufmann, San Francisco, 2000).").
Here we show that these protocols can be exploited to compute with the
communication infrastructure, transforming the Internet into a
distributed computer in which servers unwittingly perform computation on
behalf of a remote node. In this model, which we call ‘parasitic
computing’, one machine forces target computers to solve a piece of a
complex computational problem merely by engaging them in standard
communication. Consequently, the target computers are unaware that they
have performed computation for the benefit of a commanding node. As
experimental evidence of the principle of parasitic computing, we
harness the power of several web servers across the globe, which—unknown
to them—work together to solve an NP complete
problem[2](/articles/35091039#ref2 "Garey, M. & Johnson, D. S. Computers and Intractability: A Guide to the Theory of NP-completeness (Freeman, San Francisco, 1979).").