30-09-2016, 02:24 PM
1457070404-parasitic.pptx (Size: 190 KB / Downloads: 4)
INTRODUCTION
During package transfer across the internet message can
be corrupted .TCP contains a checksum that provides some data integrity.
Sender compute checksum and transmits that with message. the receiver also compute the checksum and if does not agree with the sender’s then the message was corrupted and discarded . the abstract discusses the technical aspects of what has already been carried out and related issues .
Definition
Parasitic computing is a technique in which one computer or server links to other servers and uses that equipment to provide computation capacity .It is normally , not considered hacking ,or theft of computer services because the program does not defeat any locks or safeguards on the other equipment .Rather ,a legitimate message can be delivered to the other computers .And they will provide computing capacity without any beach of security.
Details of parasitic computing
Parasitic Computing is a concept by which one can use the resources of machines that are connected on the Internet.
This technology exploits open Internet protocols to use the resources of remote machines.
As name suggests ,the machine that requires the services of others does not need to be authorized by the latter.
Implementation Using TCP
Sending a message over an Internet is a very sophisticated process as the message is processed across many layers from HTTP then to TCP then to IP layer ,going through data link layer finally to the physical layer and in the same manner the message is constructed back at the destination.
To implement this concept of parasitic computing we can choose to exploit processing theoretically any of this layers but below TCP layer it is not very beneficial.
Till now there has been only one implementation , which has exploited this concept of parasitic computing .Idea is to use some feature of the protocol in such a manner
The main target problems for such distributed environments are NP-complete problems i.e. non-deterministic polynomial problems
Implementation one first needs to have a brief idea of TCP checksum
TCP CHECKSUM
The checksum field is the 16-bit one’s complement of the sum of all 16-bit words in the header and text.
If a segment contains an odd number of header and text octets to be check summed ,The last octet is padded on the right with zeros to form a 16-bit word of checksum
The pad is not transmitted as part of the segment , While computing the checksum ,the checksum field it self is replaced with zero’s.
Information is carried in the Internet protocol and is transferred across the TCP/Network interface in the arguments or results of calls by the TCP on the IP .
ADVANTAGES
Server side parasitic computation determines the take clients
At schools, colleges and workplaces admin monitoring is achieved
Computational capacity of Remote computer is analyzed .
DISADVANTAGES
Trust Relationship is breaked
Denial of service attack without breaking security law.
Remote target computer’s ability to communicate with rest of the internet is eliminated.
CONCLUSION
TCP layer can be exploited and also cannot guarantee correctness of result due to false-positive and false-negation
At present ,parasitic computing may be slow technique to solve ,but it could be used to load heavy request on server and get the solution for its problem