In the first part of these lectures, we discussed core elements of the TCP/IP protocol suite, including the IP v.4 protocol. Now read about IP v.6 and, in your own words and using accepted source referencing standards, write about 800 words explaining the reasons why IPv6 was developed, and what new features it introduces into IP.
DiTEL
EDU 5640 Section C ASSIGNMENT PART 1 Josmar Borg
EDU 5640 - Introduction to Technology Enhanced Learning
Josmar Borg
In this report, I intend to briefly describe the TCP/IP (Transmission Control Protocol/Internet Protocol) protocol as an important layer of the OSI (Open System Interconnection) Reference Model called the ‘network layer’. No detailed explanation is given as the main focus will be on the differences between the currently used IP v.4 with the emerging version 6 …yes version 5 was never launched as it was an experimental protocol called the Internet Stream Protocol, which was never widely set up. TCP/IP is a network standard that defines how messages (data) are routed from one end of a network to another while ensuring that data arrives correctly. TCP/IP defines rules that divide ‘whole’ messages into ‘smaller chunks’ called ‘packets’ or ’datagram’. It provides addresses for each datagram, checking for and detecting errors, sequencing packets and regulates the flow of messages along a network. This technique is called ‘packet switching’. These set of rules (TCP/IP) has been adopted as a network standard for Internet communications. Therefore, all hosts on the Internet follow the same rules, thus creating a standard across all hosts. When a computer sends data over the Internet, the data is divided into packets. Each packet contains the data and a header that contains extra data such as recipient, sender address, sequence information used to assemble packets together at destination and more. IP v.4 was created in the 1970’s and an IP v.4 address is a 32 bit number, represented by 4 numbers separated by periods such as 207.46.197.32. At that time no one could foresee that a 32-bit address space, representing approximately 232 addresses (4 billion addresses) could possibly be fully exhausted. But in the early 90s there was a concern about the rapid depletion of IP addresses and this escalated by 2000 as there was an increase in IP addresses demands due to an explosion of Internet applications, games, information sources and business transactions, millions of new IPenabled mobile handsets, emerging IP-enabled sensor networks for industrial, medical, and military applications and much more. As a consequence, a new version of the protocol supporting more available addresses was needed and so, IP v.6 was adopted. IP v.6 addressing jumps all the way to 128 bits and this represents a truly remarkable increase in the address size to 2128 addresses. IP v.6 addresses are assigned as groups of 4 hexadecimal digits separated by colons such as 2001 : 0db8 : 85a3 : 08d3 : 1319 : 8a2e : 0370 : 7334. In addition, this addressing scheme also eliminates the need of the Network Address Translation (NAT) technique used to overcome the shortage of unique IP addresses for individual network resources over the Internet. NAT allows multiple resources within an organization or connected to a local LAN to use a single IP address to access the Internet. Since a new IP protocol needed to be created, thus it made sense that apart from increasing the number of bits used but also modify some of the existent features or add new features too. One important change is the address types supported. IP v.4 supported three address types: Unicast: A transmission to a single interface card. Multicast: A transmission to a group of interface cards on the network....a message sent to a multicast address goes to all devices in the group. Broadcast: A transmission that represents to all interface cards on the network Computer Science Concepts – Elements of Web Science
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EDU 5640 - Introduction to Technology Enhanced Learning
Josmar Borg
Unicast was the most addressing type used as Multicast was not widely used (it was optional) and the use of Broadcast had to be severely restricted for performance reasons. IP v.6 has Unicast like in IP v.4 and a much better Multicast addressing scheme that is required rather than being optional as in version 4. IP v.6 has no Broadcast but a new type, the Anycast address, has been added. With Anycast addressing a message must be sent to any member of a group of IP devices (the easiest to reach), and does not need to be sent to them all. A new header format was designed to keep the header from taxing the system to a minimum. This was altered by moving both non-essential fields and optional fields to extension headers that are placed after the IP v.6 header. Thus the IP v.6 header is faster and more efficiently processed especially at intermediate routers. Through the introduction of these header extensions, there is better security as there is a better implementation of encryption and authentication of the datagram sent. IP v.6 Security (IPSec) functionality is almost identical to that in IP v.4, but in version 6 the IPSec can be utilized along the entire route, from source to destination. A new feature included in IP v.6 is Extensibility, meaning that it can easily be extended for new features by adding extension headers after the IPv6 header. More added and improved features are introduced with the new emerging IP Protocol such as Mobile IP v.6. This feature allows a host to remain reachable regardless of its location in an IP v.6 network. Even though the host changes locations and addresses, the existing connections through which the host is communicating are maintained. Another feature is that IP v.6 is a Stateless Auto Configuration protocol. With IP v.4, you need a DHCP (Dynamic Host Configuration Protocol) server to assign an IP address (if not done manually). This works quite well if there is a single DHCP server, but problems arise when there is more than one server that can supply conflicting information. Another problem is that is hard to have the same address when the DHCP server is rebooted. Stateless Auto Configuration is a mechanism whereby routers send out router advertisements (RAs) that contain the upper 64 bits of an IP v.6 address, and the hosts generate the lower 64 bits themselves in order to form a complete address. This way, if all the routers send out the same prefix for the upper 64 bits, the host will always configure the same IP v.6 address for itself. No configuration is required, either on the host or a DHCP server. Generally desktops, laptops, net books and the like were connected to the Internet but through a larger IP Address pool available with the use of IP v.6 now we will see embedded systems connected to the Internet in innovative ways. Many embedded systems will now have their own IP addresses, thus eliminating the need for NAT. This will enable direct peer-to-peer communication, better security with IPSec, Quality of Service, Seamless Connectivity and Auto Configuration. All this progress would take the future the internet beyond what is now seen as impossible!
Computer Science Concepts – Elements of Web Science
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EDU 5640 - Introduction to Technology Enhanced Learning
Josmar Borg
Bibliography Das, K. (n.d.). Retrieved from IPv6.com - IPv6 and the Next Generation Internet: http://www.ipv6.com/articles/general/ipv6-the-next-generation-internet.htm Kozierok, C. M. (2005, September 20). Retrieved from The TCP/IP Guide : http://www.tcpipguide.com/free/index.htm Network Broadcasting and Multicasting. (n.d.). Retrieved from http://www.comptechdoc.org/independent/networking/guide/netbroadcasting.html Noteboom, L. A. (2007). What is TCP/IP V.6? Retrieved from Ask LEO: http://askleo.com/what_is_tcpip_v6.html Quasney, J. J., Sebok, S. L., & Freund, S. M. (2010). Chapter 9: Communications and Networks. In Discovering Computers 2010: Living in a Digital World, Complete (p. 478). USA: RRD Menasha.
Computer Science Concepts – Elements of Web Science
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