Nowadays the number of people who are using Internet is dramatically increasing. With no hesitation, it can be said that the Internet is indeed the most popular media of communication prevailing in the present world scenario. But many of the users are nowadays facing the problem of failure in maintaining the connection with the cyber world. The solution to the problem is RAIN-Reliable Array Of Independent Nodes developed by the California Institute of Technology (Caltech), in collaboration with NASA's Jet Propulsion Laboratory and the Defense Advanced Research Projects Agency (DARPA). RAIN technology was able to offer the solution by minimizing the number of nodes in the chain connecting the client and server and also by making the existing nodes more robust and independent of each other. Also RAIN technology provides the novel feature of replacing a faulty node by a healthy one there by avoiding the break in information flow. In effect with the aid of RAIN connection between a client and server can be maintained despite all the existing problems.
Keywords: Rainfinity, fail-over protocols.
The Internet is changing the way that people manage and access information. In the last five years, the amount of traffic on the Internet has been growing at an exponential rate. The World Wide Web has evolved from a hobbyists' toy to become one of the dominating media of our society. Ecommerce has grown past adolescence and multimedia content has come of age. Communication, computation and storage are converging to reshape the lives of everyone. Looking forward, this growth will continue for some time. The question is: what can we do to scale the Internet infrastructure to meet this growth?
There are four trends in the current growth of the Internet:
- Internet clients are becoming more numerous and varied. In addition to the ever-increasing number of PCs in offices and homes, there are new types of clients, such as mobile data units, (cell phones, PDAs, etc.) and home Internet appliances (set-top boxes, game consoles, etc.) In the next five years, these new types of Internet devices will pervade the Internet landscape.
- To support these new clients, new types of networks are being designed and implemented. Examples are wireless data networks, broadband networks and voice-over-IP networks. Technologies are being developed to connect these new networks with the existing Internet backbone.
- The content delivered over the Internet is evolving, partly because of the emergence of the new clients and new networks. There will be a growing presence of multimedia content, such as video, voice, music and gaming streams. The growth in content adds not only to the volume of the traffic, but also to the computation complexity in transporting and processing the traffic, thus accelerating the convergence between communication and computation.
The primary function of the Internet is for information to flow from where it is stored, traditionally known as a server, to where it is requested, commonly referred to as a client. The Internet is the network that interconnects all clients and servers to allow information to flow in an orderly way. While people become more and more dependent on this network, they demand that it become faster and more reliable. As a result, reliability and performance are becoming key challenges in many parts of the Internet infrastructure.
The communication path between a client and a server can be viewed as a chain. Each device along the path between the client and the server is a link in the chain. For example, for a user to receive a HTML page from yahoo.com, he or she would issue a request, which travels from the user's client, through a number of routers and firewalls and other devices to reach the Yahoo web server, before the data will return along the same or a similar chain. The strength of this chain, both in terms of throughput and reliability, will determine the user experience of the Internet. So, how do we make this chain stronger?
A chain is only as strong as its weakest link, and the longer the chain, the weaker it is overall. To increase reliability and performance, one should look for ways to reduce the number of links in the chain, and make each remaining link more robust. The weak links in the Internet infrastructure are single points of failure and performance bottlenecks. Single points of failure are devices that have no inherent redundancy or backup. Bottlenecks are devices that do not have enough processing power to handle the amount of traffic they receive. Rainfinity 's RAIN technology was invented to eliminate single points of failure and performance bottlenecks in the Internet infrastructure. In the chain of links analogy, it is equivalent to strengthening one link without adding additional links. In some cases, it may even allow several links to be consolidated into one.
The key to reliability is redundancy. If one device fails, there must be a second device ready and able to take its place. If the second device fails, there must be a third, and so on. The key to performance is processing power. To increase capacity and speed, the customer has the choice of using a bigger, faster processor, or by dividing the task among several processors working in concert. Using a single processor limits scalability to the state of the art in processors, so that performance can only be what Moore's Law will allow. Multiple processors working in a cluster provide a more flexible and scalable architecture. Capacity can be added or subtracted at will; the overall performance to price ratio is higher; and combined with intelligent fail-over protocols; such a cluster enables higher reliability.
A clustering approach must allow multiple machines to work together as if they were a single system. The key challenge here is that all the machines in the cluster need to have consensus on the exact state of the cluster, and make collective decisions without conflicts. To address the issue of reliability, a cluster must also allow healthy machines within the cluster to automatically and transparently take over for any failed nodes. To address the issue of performance, all healthy nodes in the cluster must be actively processing in parallel, and each additional node must add processing power to the group, not detract from it. Creating such a clustering solution for the Internet infrastructure is an extremely difficult task.