Direct Use Of The Underlying Network Service example essay topic

The Internet has transformed the computer and communications world like nothing before. The Internet is also known as the world-wide web, which has the capability of gathering information, and can communicate between individuals and their computers no matter where the geographic location. The Internet started some thirty years ago; it has been one the best investments that researchers have spent their time and commitment on. Today millions of people use the internet.

The Internet is a widespread information infrastructure. Its history is complicated and its influence reaches not only to the technical fields of computer communications but throughout society as we move toward increasing the use of online tools to accomplish electronic commerce, information acquisition, and community operations. The Internet History The original name of the Internet was the Arpanet. The internet was based on the idea that there was going to be more than one independent network, with the Arpanet as the ground-breaking packet switching network. The Arpanet would soon include ground based packet radio networks, packet satellite networks, and other networks.

In this approach, the choice of any individual network technology was not dictated by particular network architecture but rather could be selected freely by a provider and made to work with the other networks. Up until that time there was only one general method for federating networks. This was the traditional circuit switching method where networks would interconnect at the circuit level, passing individual bits on a synchronous basis along a portion of an end-to-end circuit between a pair of end locations. 1 1. Cerf, Vinton Pages 10-20 In 1961 Klein rock showed that packet switching was a more efficient switching method.

Distinctive purpose interconnection preparations between networks were another possibility, along with packet switching. While there were other limited ways to interconnect different networks, they required that one be used as a component of the other. As an open-architecture network, individual networks could be designed separately and developed so each can have its own distinctive interface which it may offer to users and other Internet providers. Each network can be designed in accordance with the specific environment and user requirements of that network. There are typically no constraints on the type of network that can be included.

Open architecture networking was introduced by Kahn in 1972, after his arrival at DARPA. This work was originally part of the packet radio program, but then became a separate program in its own right. The program was called "Internet ting" at that particular time. Kahn thought about developing a local protocol available only to the packet radio network, that would avoid having to deal with the massive amount of different operating systems, and continuing to use NCP (network control protocol).

However, NCP did not have the capability to address networks (and machines) further downstream than to destination IMP on the ARPANET. So some changes to NCP would have to be done. (The assumption was that the ARPANET was not changeable in this regard). NCP relied on ARPANET to provide end-to-end consistency. If any packets were lost, the protocol would come to a halt. 2 1.

Cerf, Vinton, Pages 10-50 Kahn developed a new version of the protocol which could meet the needs of an open-architecture network environment. This protocol would eventually be called Transmission Control Protocol / Internet Protocol (TCP / IP). While NCP tended to act like a device driver, the new TCP / IP would be more like a communications protocol. Four rules were critical to Kahn's early thinking: 1. Every separate network would have to stand on its own and no internal changes could be required to any network to connect to the Internet. 2.

Communications would be on a best effort basis. If a packet didn't make it to the final destination, it would shortly be retransmitted from the source. 3. Black boxes would be used to connect the networks; these would later be called gateways and routers.

There would be no information retained by the gateways about the individual flows of packets passing through them, thereby keeping them simple and avoiding complicated adaptation and recovery from various failure modes. 4. There would be no global control at the operations level. There were also other key issues that needed to be addressed: Algorithms were needed to prevent lost packets from permanently disabling communications and enabling them to be successfully retransmitted from the source. There was a need for host to host 'pipe lining', so that multiple packets could be en route from source to destination at the carefulness of the participating hosts, if the intermediate networks allowed it.

There was a use for gateway functions to forward packets appropriately. This included interpreting IP headers for routing, breaking packets into smaller pieces if necessary, and handling interfaces. The need for end-end checksum's, reassembly of packets from fragments and detection of duplicates, and the need for global addressing. 3 1.

Cerf, Vinton pages 45-50 There were more concerns about techniques for host to host flow control, and interfacing with the various operating systems. While working at BBN Kahn began working on a communications-oriented set of operating system principles. Kahn realized it was necessary to learn the performance level of each operating system. This would embed any new protocols in an efficient way.

In the spring of 1973 Kahn asked Vint Cerf to work with him on the detailed design of the protocol. Cerf was deeply involved in the original design and development of the NCP. He already had the knowledge about interfacing to existing operating systems. They teamed up to spell out the details of what became TCP / IP. These are some basic approaches that emerged from this collaboration between Kahn and Cerf: o Communication between two processes would logically consist of a very long stream of bytes (they called them octets).

The position of any octet in the stream would be used to identify it. o Flow control would be done by using sliding windows and acknowledgments. The destination could select when to acknowledge and each acknowledgement returned would be cumulative for all packets received to that point. o It was left open as to exactly how the source and destination would agree on the parameters of the windowing to be used. Defaults were used at first. The Arpanet / Internet was designed only to be used on a national level; little did they know what was in store for the future. Then a 32 bit IP address was used, the first 8 bits signified the network and the remaining 24 bits designated the host on that network.

It was assumed, that 256 networks would be sufficient for the unpredictable future, it was clearly in need of rethinking when LANs began to appear in the late 1970's. 41. Cerf, Vinton Pages 60-81 Cerf and Kahn described TCP, as providing all the transport and forwarding services in the Internet. Kahn intended that the TCP protocol would support a range of transport services, from the reliable sequenced delivery of data to a service in which the application made direct use of the underlying network service, which might imply an occasional lost, corrupted or reordered packets. Early motivation for both the ARPANET and the Internet was resource sharing. Connecting the two together was far more economical than duplicating these very expensive computers.

Though file transfer and remote login were very important applications, electronic mail has probably had the most significant impact of the innovations from that time. Email provided a new way of how people could communicate with each other, and changed the nature of collaboration, first in the building of the Internet itself and later for much of society. There were other applications proposed in the early days of the Internet, including packet based voice communication, various models of file and disk sharing, and early 'worm' programs that showed the concept of agents and, viruses. A key concept of the Internet is that it was not designed for just one application, but as a general infrastructure on which new applications could be conceived. Commercialization of the Internet Commercialization of the Internet involved not only the development of competitive, private network services, but also the development of commercial products implementing the Internet technology. 51.

Cerf, Vinton Pages 60-812. Quarterman, John Pages 30-43 In the early 1980's, dozens of vendors were incorporating TCP / IP into their products because they it was a good way for networking. Sadly they lacked both real information about how the technology was supposed to work and how the customers planned on using this approach for networking. The DOD had mandated the use of TCP / IP in many of its purchases but gave little help to the vendors regarding how to build useful TCP / IP products. In 1985 Dan Lynch was working with LAB; he had arranged a three day workshop for all vendors to come learn about how TCP / IP worked. Most of the speakers came from the DARPA research community who had both developed these protocols and used them in day to day work.

The results were surprises on both sides: the vendors were amazed to find that the inventors were so open about the way things worked and the inventors were pleased to listen to new problems they had not been considered, but were being discovered by the vendors in the field. After two years of conferences, tutorials, design meetings and workshops, a special event was organized that invited those vendors whose products ran TCP / IP well enough to come together in one room for three days to show off how well they all worked together and also ran over the Internet. In September of 1988 the first Interop trade show was born. Like the commercialization efforts that were highlighted by the Interop activities, the vendors began to attend the IETF meetings that were held 3 or 4 times a year to discuss new ideas for extensions of the TCP / IP protocol suite. 61. Quarterman, John Pages 30-43 Starting with a few hundred attendees mostly from academia and paid for by the government, these meetings now often exceed a thousand attendees, mostly from the vendor community and paid for by the attendees themselves.

We have seen a new phase of commercialization in the last few years. In the start of commercialization, commercial efforts mainly comprised vendors providing the basic networking products, and service providers offering the connectivity and basic Internet services. The Internet has now become almost a 'commodity's ervice, and much of the latest attention has been on the use of this global information infrastructure for support of other commercial services. This has been greatly accelerated by the widespread and rapid adoption of browsers and the World Wide Web technology, allowing users easy access to information linked throughout the globe. The Internet Today The Internet is much more than what it initially started out to be more than two decades ago. The Internet was founded during the time of time-sharing, but has survived into the time of personal computers, client-server and peer to peer computing, and the network computer.

It was designed before LANs existed, but has accommodated that new network technology, as well as the more recent ATM and frame switched services. It was seen as supporting a range of functions from file sharing and remote login to resource sharing and collaboration, and has spawned electronic mail and more recently the World Wide Web. But most important, it started as the creation of a small band of dedicated researchers, and has grown to be a major success, making billions of dollars yearly. 7 1. Quarterman, John Pages 30-432. web Internet is now changing to provide new services like, real time transport, in order to support audio and video streams. The Internet also allows the availability of networking along with powerful affordable computing and communications.

This evolution will bring us new applications. It is evolving to permit more sophisticated forms of pricing and cost recovery. It is changing to accommodate another generation of fundamental network technologies with different characteristics and requirements, from broadband residential access to satellites. New modes of access and new forms of service will grow to new applications, which in turn will drive further evolution of the net itself. With the success of the Internet has come a proliferation of stakeholders - stakeholders now with an economic as well as an intellectual investment in the network.

Today there are debates over control of the domain name space, the form of the next generation IP addresses, and a struggle to find the next social structure that will guide the Internet in the future. The form of that structure will be harder to find, given the large number of concerned stake-holders. At the same time, the industry struggles to find the economic rationale for the large investment needed for the future growth. The Internet has evolved tremendously over the past decades, since the started out of the Arpanet. The evolution of the TCP / IP was a major success, with the start of commercialization of the protocol. Eventually the public would get their hands on this new type of networking.

Today we have the World Wide Web and it is used all across the world. The internet brings in billions of dollars a year, and many companies earn a living from the internet today. 8 1. web people can communicate through instant messenger and email through the internet. People can also receive and send information. The internet makes things so much easier for people.

There is no telling what the internet holds in the future, hopefully it's as easy and fun as today.