QUESTION 1: Why do we need protocols in computer networks? Discuss in your own words.
A network protocol is a formal set of rules, conventions and data structure that governs how computers and other network devices exchange information over a network.Network engineers have written rules for communication that must be strictly followed for successful pc-to-pc communication. If we don’t use these protocols then we can’t do successful networking. So we need these protocols which apply to different layers of sophistication such as:
In modern protocol design, network protocols are "layered" according to the OSI 7 layer model or similar layered models. Layering is a design principle which divides the protocol design into a number of smaller parts, each of accomplishes a particular sub-task, and interacts with the other parts of the protocol only in a small number of well-defined ways. Layering allows the parts of a protocol to be designed and tested without a combinatorial explosion of cases, keeping each design relatively simple. Layering also permits familiar protocols to be adapted to unusual circumstances.
The need for protocols also applies to network devices. Computers have no way of learning protocols, so network engineers have written rules for communication that must be strictly followed for successful host-to-host communication. These rules apply to different layers of sophistication such as which physical connections to use, how hosts listen, how to interrupt, how to say good-bye, and in short how to communicate, what language to use and many others.
Detection of the underlying physical connection (wired or wireless), or the existence of the other endpoint or nodeNegotiation of various connection characteristicsHow to start and end a messageHow to format a messageWhat to do with corrupted or improperly formatted messages (error correction)How to detect unexpected loss of the connection, and what to do nextTermination of the session and or connection.From the features stated above, we could understand the need for protocols in networking.
QUESTION 2: In internet IP Version 4 is going to be replaced by IP Version 6, discuss the major factor behind this change.
IPv4 is currently update the dominant Internet Protocol version, and was the first to receive widespread use. In December 1998, the Internet Engineering Task Force (IETF) designated IPv6 as the successor to version 4IPv6 has a much larger address space than IPv4. This results from the use of a 128-bit address, where IPv4 uses only 32 bits. The new address space thus supports 2128 (about 3.4×1038) addresses.The following are the major reasons for that if the IPv4 is replaced by IPv6:-.
A recent study by google indicates that penetration is still less than one percent of Internet traffic in any country. The leaders are Russia (0.76%), France (0.65%), Ukraine (0.64%), Norway (0.49%), and the United States (0.45%). Although Asia leads in terms of absolute deployment numbers, the relative penetration is smaller (e.g., China: 0.24%). IPv6 is implemented on all major operating systems in use in commercial, business, and home consumer environments.IPv6 has better security, because the IPSec security frame-Work is mandatory in IPv6, while it is optional in IPv4;Plug-and-play capabilities have been improved;There are improvements with Quality of Service because of an additional flow label in the IPv6 header.Peer-to-peer communication is simplified, because the huge number of IP-addresses makes address translation obsolete.IP mobility with IPv6 has been simplified because, unlike IPv4, we can rely on a communication partner’s address to be visible throughout the Internet.
The new generation of Internet Protocol provides more addresses than ever will be needed: theoretically, every square millimeter on earth could be provided with many billions of addresses.A remaining and most important advantage of IPv6 over IPv4 is the vast number of IP-addresses it provides to the Internet world.
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