Parasitic ComputingAritra Mukherjee

If you’re one in a billion in INTERNET..

…..there are millions of people like you.

Who Are Being Used..

In the world of internet, millions of peopleJust like you…

And You Will Never K

now

Someone else is using your computer

He is slowing your Connection Speed for his own purpose..

No, Its Not Cracking…

You are a victim of Parasitic Computing..

What is Parasitic Computing?

First Reported in journal ‘Nature’ in 2001 by Barabasi, Freech, feong and Brockman

A form of Distributed Computer Architecture

Used for solving Complex Computational Problems

Target could never know

Exploit Standard set of communication protocol in internet.

Potential standard protocols are TCP, HTTP, IP

To know how it works we need to know something first….

How The Communication through Internet is done?

When a user selects a URL….

Actions at Sender

Open a TCP connection to web server

Issues a HTTP request over TCP connection

TCP message is carried via IP

Establishing TCP Connection

Initiator Node

Acceptor Node

Connection Established

SYN

SYN+ACK

ACK

Time→

When a user selects a URL….

Actions at receiver

Recieve message through IP

Validate checksum at TCP

Validated pushed to HTTP

Not validated discard the packet

Internet Communication

HTTP > TCP > IP > TCP > HTTP

Implementation Implementation takes place at

many layers in internet

Several protocols may be exploited to perform parasitic computing

Implementation made using TCP or higher levels

Implementation Using TCP

TCP Checksum

Provide enough logic to compute any Boolean function.

HTTP Service

Protocol always send a response to any message received.

TCP Checksum

The Proof of Concept..

Solved 3 SAT problem

Solved other NP- Complete Problems..

How it works…

A Single home parasite node initiates the computation

Sends a specially created TCP packet containing a possible solution.

If the possible solution is correct, the HTTP server returns an error message.

If the solution is wrong, then packet is dropped at TCP Layer

Creating Parasitic Message

The problem is constructed as the data part

TCP checksum sent is a representation of expected answer

Parasitic checksum and the variable string are sent to the remote machine for verification

Algorithm

S= create TCP segments (x1, x2, x3, x4……….x15)S.checksum = checksumfor each x

S.data = pad with zeros (x)send Sreceive answerif answer = true

write x as a solution

Prototype of Parasitic Computing

Problem for Parasite

Several computational cycles are taken to process the solutions

Possibility of false negative

Possibility of false positive

Problem for Servers

Delay due to the parasitic message could cause a denial of service

Almost impossible to prevent

Removing or changing the exploited functions would cause the server unable to communicate.

Ethics in Parasitic computing

Future…

Computation to communication ratio must increase.

Exploiting HTTP or encryption / decryption could execute in an efficient manner.

The ethical dilemma could lead it to a vulnerable future..

Parasitic Computing logically moves computation onto the communication infrastructure of internet, blurring the distance between computation and communication

References

Barabasi et.al. Parasitic Computing, NATURE 412, 30 Aug 2001. Barabasi et.al. Supplement material for Parasitic Computing: http://www.nd.edu/~parasite/ Barger N. Robert & Crowell R. Charles, The ethics of Parasitic Computing, Sept 2003 : www.nd.edu/~ccrowell/Parasitic%20Computing.pdf

Ivars Peterson, Sneaky Calculations, Science News 160, 17 Nov 2001. www.hindu.com/thehindu/2001/09/13/stories/08130001.htm