Q2. Describe the important and distinguishing properties of Peer to Peer computing and the Grid.

How is this Peer to Peer and the Grid architecture changing work flow and service-oriented applications?

Answer:

Peer to Peer (P2P) means computer network uses diverse connectivity between diverse connectivity between participants in a network and the cumulative bandwidth of network participants rather than conventional centralized resources where a relatively low number of servers provide the core value to a service or application. P2P networks are typically used for connecting nodes via largely ad hoc connections. Such networks are useful for many purposes. Sharing content files containing audio, video, data or anything in digital format is very common, and real time data, such as telephony traffic, is also passed using P2P technology. A pure P2P network does not have the notion of clients or servers but only equal peer nodes that simultaneously function as both "clients" and "servers" to the other nodes on the network. This model of network arrangement differs from the client-server model where communication is usually to and from a central server. (Wikipedia, 2009)

Grid Architecture / Computing is a parallel processing architecture in which CPU resources are shared across a network, and all machines function as one large supercomputer. A well known example of grid computing in the public domain is the ongoing Search for Extraterrestrial Intelligence (SETI) in which thousands of people share the unused processor cycles of their PCs in the vast search for signs of rational signals from outer space. Grid computing depends on the software to divide and apportion pieces of a program among several computers. It is cost-effective and can solve problems that can’t be approached without an enormous amount of computing power. (4to40.com, 2009)

With my own words, P2P computing shares bandwidth among each peer nodes and Grid computing shares CPU power amongst network' machines. P2P and Grid Computing are important nowadays. It is because the multimedia becomes popular. Multimedia containing Video, Audio, Image and Sound is always a big file in size. The traditional client/server file transfer like FTP becomes insufficient for such large file (eg. over 1G file). As a result, P2P and Grid computing would be the cost-saving solution for multimedia information sharing. P2P and Grid computing have changed the work flow and service-oriented applications because the client/server method cannot share huge data in the limited resources, like bandwidth and CPU power.

The following Diagram-7 from Wikipedia and 4TO40.com shows P2P, Grid and Client/Server computing.

Diagram-7, P2P, Grid & Client/Server


Reference:

1. Wikipedia (2009). "Peer-to-Peer". Wikipedia The Free Encyclopedia, Retrieved Mar-15th-2009 from URL - http://en.wikipedia.org/wiki/Peer_to_peer
2. 4to40.com (2009). "Question: What is Grid Computing?". 4to40.com, Retrieved Mar-15th-2009 from URL - http://www.4to40.com/qa/index.asp?id=3303