Peer-to-peer (P2P) networks have become very popular of late. This is because of its ability to allow distributed users to share their resources, good bandwidth, and content from the edge of the Internet. The node of the P2P network functions as both a server and a client. This is contrary to the old server-client model that has a workstation, which operates, either as a client or a server. In this model, it is only the server that is capable of distributing its resources to the other computers (clients), therefore, making the clients highly dependent on the server. This network restricts certain files and programs only to the server such that the other machines cannot be able to access such resources. This is done as a way of ensuring the privacy of some sensitive documents in the office being accessed by unauthorized users. Hence server-client network symbolizes an example of a centralized network where most of the activities are restricted only to the server. This puts such a network in great danger because most of the activities in the network can stop in case the server crashes. On the other hand, a peer-to-peer network is a network that has an architecture that facilitates all the computers in the network to download from and provide materials to each other.
In a peer-to-peer network, all the computers possess the same power and, therefore, serve as a server and client simultaneously. This architectural arrangement facilitates direct communications of the computers without relying on a server as a mediator. Hence in this network computers exchange their contents directly.
The P2P model has a number of merits which makes it one of the best networks at the moment. One of its strengths lies in the good design of its architecture. These designs include centralized, decentralized, and hybrid models. The design of the centralized model architecture is designed to allow this network to possess a centralized directory that stores an index of P2P content, with the physical copy of the contents still residing on the individual peers. This makes the processing requests impose low overheads on individual peers. The strength of this network is its big bandwidth, which enables serving a large number of users with plenty of data at an affordable fee, which is free sometimes which is not possible with other current networks.
For example, the cost of serving about ten million users with ten petabytes is very huge for other networks but very convenient and cheap in a peer-to-peer network. This is made possible by the ability of this network to use its spare bandwidth, storage, and processing cycles. Therefore, this network has greatly boosted the minor producers in their production and distribution of materials like songs due to its affordability. Also, the major companies are currently using this network to promote their music through the use of free sampling on the network. On the other hand, this network has some problems. These shortcomings are; the centralized P2P index that makes the central server act as a bottleneck and a single point of failure. The other problems of this network include the failure of the peers to consider their impacts on the consumption of the network resources by other users. This occurs when one user sends so many download requests that the responding node becomes very busy processing requests of other users. This network has a problem of promoting illegal distributions such as piracy. The advantages of the server-client network include the ability to produce information (report) that is very efficient and reliable. This is because it does not allow unauthorized users to access its resources. There is also no sharing of processors like in the peer-to-peer network. The other advantage is that in this network the application programs are tailored very well to meet the end-users needs. The major problem is its inability to allow a free exchange of resources among the workstations.