AbstractThe number of internet users are rapidly increasingenormously now a days.
The user avails the services of the Internet throughdifferent types of devices like computer, mobile etc. the internet protocolprovide the connectivity the connectivity and identification of these device ofthe internet. In this paper we discuss the Internet Protocol Version 4, itsfeature and shortcomings, Internet Protocol Version 6, its features, deploymentissues and the techniques to migrate from Internet Protocol Version 4 (IPV4) toInternet Protocol Version 6 (IPV6).Keyword- IPV4, IPV6, the Internet, Transition, Translation,Tunnelling, Dual Stack, Introduction The Internet Protocol Version4 which is in use in the today’s Internet was lunched in 1980s but due to somelimitation the Internet Engineering Task Force (IETF) decided to launch a newversion in 1991 in order to overcome the shortcomings of IPV4. The use ofinternet is increasing day by day.
There are many daily activities that needthe users to be connected with The Internet and there are enormous serviceslike social networking and websites, video call and chatting .To avail theseservice, it is necessary to be a part of The Internet. To be connected with TheInternet we use devices like computer, mobile phone, tablet, handheld devices andpersonal digital assistant (PDA).
Allthese devices can communicate with each other through the network using internetprotocol (IP).It is pertinent to mention that each and every device has aunique Internet Protocol address in order to communicate with other devices inThe Internet. Due to large number of users the IPV4 addresses become exhausted.Migration from Internet Protocol Version 4 to Internet Protocol Version 6 wasimpossible instantly due to the huge number of IPv4 users. Literature ReviewInternet Protocol version 4 (IPv4) is the fourth version of the InternetProtocol (IP) and it is the first version of the protocol to be widelydeployed. Together with IPv6, it is at the core of standards-basedinternetworking methods of the Internet. IPv4 is still by far the most widelydeployed Internet Layer protocol. It uses a 32 bit addressing and allows for4,294,967,296 unique addresses.
Even though the name seems to imply that it’sthe fourth iteration of the key Internet Protocol, version 4 of IP was thefirst that was widely used in modern TCP/IP 3. IPv4, asIt is sometimes called to differentiate it from the newer IPv6, is theInternet Protocol version in use on the Internet today, and an implementationof the protocol is running on hundreds of millions of computers. It providesthe basic datagram delivery capabilities upon which all of TCP/IP functions andit has proven its quality in use over a period of more than two decades. 3Internet Protocol version 6 (IPv6) is a version of theInternet Protocol (IP) intended to succeed IPv4, which is the protocolcurrently used to direct almost all Internet traffic. IPv6 stands for InternetProtocol version 6 also known as Ipng (IP next generation) is the secondversion of the Internet Protocol to be used generally across the virtual world.The first version was IPv4.
3 IPng was designed to take an evolutionary stepfrom IPv4. It was not a design goal to take a radical step away from IPv4.Functions which work in IPv4 were kept in IPng. Functions which didn’t workwere removed. The Internet operates by transferring data between hosts inpackets that are routed across networks as specified by routing protocols.These packets require an addressing 3Scheme, such as IPv4 or IPv6, to specify their source and destinationaddresses. Each host, computer or other device on the Internet requires an IPaddress in order to communicate.
The growth of the Internet has created a needfor more addresses than are possible with IPv4. Like IPv4, IPv6 is aninternet-layer protocol for packet switched internetworking and providesend-to-end datagram transmission across multiple IP networks. While IPv4 allows32 bits for an IP address, and therefore has 232 (4 294 967 296) possibleaddresses, IPv6 uses 128-bit addresses, for an address space of 2128(approximately 3.4×1038) addresses. This expansion allows for many moreDevices and users on the internet as well as extra flexibility inallocating addresses and efficiency for routing traffic. It also eliminates theprimary need for network address translation (NAT), which gained widespreaddeployment as an effort to alleviate IPv4 address exhaustion. 3Transitionto IPv6 The IPv6 and IPv4 are notcompatible protocols, thus, the resources available over IPv6 cannot be reachedby IPv4 node and vice versa. Fortunately, the network architecture allows theusage of these two protocols in parallel which make the transition from IPv4 toIPv6 done smoothly.
2There are different strategiesfor transition from IPv4 to IPv6 such as • Upgrade the wholenetwork architecture along with the operating systems and applications to beIPv6 compatible. This option will guarantee the maximum benefit from all IPv6features but it is very expensive. • Wait for the last minuteto deploy, which means nothing will be used from IPv6 features till IPv4address exhaustion. This option is very risky and will lead to loss of marketshare. • As a middle strategy,the deployment to IPv6 could be made at incremental levels, which guarantee thebenefit from IPv6 features and at the same time it will lower the cost ofdeployment and allow the risk management.
From our research, we havefound that many countries prefer to follow the incremental transition of IPv6.2Although NAT in IPv4 helped reduce the number of public IP addressesneeded in an organization, NAT still has some security and performance issues.NAT being good for client server communication such as email and web has issueswhen it comes to peer-peer communication. IPv6 provides an end to end networkconnection which is a peer-peer system used in applications like VOIP. It alsohas an auto configuration system that allows clients to communicateindependently without any need for a manual setup and also makes use of IPSeccompulsorily in all its communication. This make IPv6 more secure thanIPv4.
Also, because IPv4 has fewer addresses than IPv6, this will require theuse of proxies and other forms of network mapping, thereby increasing the riskin packet sniffing through proxies but IPv6 contains more address space therebyreducing the use of proxies and ultimately increasing the level of security onthe network. 4Global DeploymentInitiatives and Policies Since the deployment of IPv6 has not been done atglobal scale in all countries, lot of deployment problems are still unknown. Inorder to uncover any problem related to the movement towards IPv6; governmentpolicies and global experiments and awareness campaigns have been set up suchas World IPv6 day and Test-Bed.
2I. World IPv6 day: the idea wasstarted on the 6th of June 2012 when major Internet service providers (ISPs),home networking manufacturers and web companies around the world united tolaunch a new era for the Internet by collaborating in a 24-hour globalexperiment – World IPv6 Day. The goal of this day is to discover the problemsand challenges regarding movement towards IPv6 and to find solutions for theseproblems. More than 300 organizations participating in the Day have enabledIPv6 for their products and services and advertised both IPv4 and IPv6addresses in the DNS 2II. Test-bed: Test bed allows the examination of the IPv6environment (development, testing, and deployment) without breaking theproduction network. There are various Test-bed experiments made around the worldwe will discuss some of them below. • Worldwide Test bed – The 6bone: since many peopleand network manufactures and vendors started to implement and experiment theIPv6; this test bed was established to give more support for the evolution anddevelopment of IPv6.
It was first started at 1996. • Indonesia Test Bed: this started when the”Institute Teknologi Bandung” (ITB) in Indonesia was connected to the”Asian Internet Interconnection Initiatives” (AI3) in order tosupport the academic research on this field. 2 III. InternationalPolicies: a national IPv6 network wasestablished to support the practical testing and usage of IPv6 technology bymany developers, researchers and operators around the world.
The network wasestablished by many countries such as India, Korea and Japan. 6. some of theimportant examples are shown below: • India: In 2004, the Minister of Communicationsand Information Technology declared the Ten Point Agenda to boost IT andcommunications, and includes the migration to IPv6.
6• Japan: Japan believes that IPv6 is very helpfulin leveraging the Internet to rejuvenate Japanese economy. Because of that,Japanese took a leadership to design a roadmap for IPv6 in 2000. Japanesegovernment forced the incorporation of IPV6 and decided a deadline forupgrading all existing systems in both public and business sectors. On 2003,the Japanese government announces a tax credit program that eliminates thetaxes from the purchase of any IPv6 routers. • South Korea: In 2003, the South Korean Ministryof Information and Communication announced its funding to the IPv6 products andservices as a promotion program. • China: In 2003, the Chinese government started aplan to make their network fully operated on IPv6 by the end of 2005. Thegovernment issued licenses and assigned budget for the construction of the”China Next Generation Internet” (CGNI). DiscussionInternet Protocol Version4(IPV4) Internet protocol version 4(IPV4)has been introduced in The Internet since the early 1980s .
It is the fourthversion of Internet Protocol (IP). IP networks provides host to host connectivity and addressing scheme used to identify each andevery device connected with the network and follow datagram (connectionless)model of data delivery. This service model issometimes called best effort 9Because although IP makes every effort to deliver datagrams, it makes noguarantees. Examplesof IPV4 addresses are:192.168.0.0123.120.
4.5 The packet format is ofthe Internet Protocol Version 4 is Version Hlen TOS Length Iden Flags Offset TTL Protocol Checksum SourceAddr DestinationAddr Options Padding Data The version filedspecifies the version of the IP Hlen field specifies thelength of headerTOS field to allow packetsto be treated differently based on application needsLength field describes thelength of the datagramIden, Flags and Offsetfields are used in fragmentation.TTL field this field isused to count the number of hopes the packet passesProtocol Field: This fieldis used to identify the upper layer protocol to which the packet should bepassedChecksum field: This fieldis used for error checkingSourceAddr field: It showsthe address of the source hostDestinationAddr field:This shows the address of the destination host on the network Option field: This fieldgives to add different options in the IP headerPad field: When the sizeof the packet is lessen the 46 bytes then padding field is used for padding In 1977 IP address shouldbe 32 bit, was decided after long discussion. It was invented by Robert Kahnand Vint Carf. The total possible IP addresses are almost 4.
3 billion. At thebeginning it was considered that these IP address are sufficient to uniquelyidentify each and every device connected with The Internet. The Internet Protocoladdress consists of five classes which are:Class AIn Class A the maximumnumber of network are 126 and number of hosts are 16 million. Largeorganization having huge number of users acquire Class A addressClass BThe number of network andhosts are 16 thousand and 64 thousands respectively.
The organizations whoseusers are in thousands prefer to use Class B address. Huge pressure on thisClass have been observed over the yearsClass CIn Class C the number ofnetworks are 2 million and number of possible hosts are 256. The smallorganization having hundreds of users obtain class C address.Class DClass D address have beenreserved for multi casting but the Internet router never allowed it except infew cases.Class EClass E addresses havebeen reserved for future use and experimental purpose.
Each class allocated a certain number of bitsfor the network portion of address and rest of the bits are for hosts. Class’sD addresses are reserved for multicasting and routers on The Internet did not supportmulticasting except few virtual private network. To differentiate between anetwork address and hosts, subnet masks are used in IP addressing scheme. Forexample an IP address 192.168.
0.1 with sub net masks 255.255.255.
0identifies the network and 1 identifies a host.On Feb 2011 the InternetCorporation for Assigned Names and Numbers (ICANN) released the last block ofIP address. It means new organization cannot obtain new IP address. The IPV4addresses become short due to assigned of IP address inefficiently. If anOrganization has 10 nodes, then it can obtain class c address it means 256addresses are assigned to that organization. 10 addresses can be used and remainingaddresses will be wasted. An organization having 260 nodes can obtain class Baddress. It means we are using 260 IP addresses out of 65, 536 IP addresses Inthis case for example address assignmentefficiency in 256/65,536 … To overcome this inefficient assignment of IPaddress following methods/ techniques have been introduced:Network AddressTranslation (NAT)Classes Internet Domain Routing(CIDR)Dynamics HostConfiguration Network Address Translation(NAT) It allows multiple devicesto use local private address within an enterprise with sharing one or moreglobal IPV4 address for external communication .
NAT translates public IPaddresses into private IP network. By using NAT the Internet Service Providers(ISPS) do not need to assign individual IP address to each and every customer’sdevice. It assign a single IP address to a costumer and this address can be usevia NAT to provide more private IP address to other devices.
The costumer mayhave thus enabling more IP address to be available to more customers Classes Internet DomainRouting (CIDR)Classless inter domain routing (CIDR, pronounced “cider”) is a techniquethat addresses two scaling concerns in the Internet: the growth of backbonerouting tables as more and more network numbers need to be stored in them, andthe potential for the 32-bit IP address space to be exhausted well before thefour-billionth host is attached to the Internet.Shortcomings of IPV41) IPV4 has the followingshortcomings /limitations Addressing spaceDay by day the numbers ofusers are increasing enormously. Of course these internet users are usingvarious kinds of devices like mobile, computer, tablets and PDA. The IPV4addresses are limited 4.3 billion out of these 4.
3 billion addresses a largenumbers of IP address wasted due to inefficient assignment. It was the core shortcomingof IPV4 that it cannot accommodate more hosts. 52) Security IPV4 does not provide anysecurity when packets are transmitted. Security like authenticating packets or encryptionso that to avoid unauthorized access to packets during transmission process .Securityfeature was optional in IPV43) Network congestion IPV4 has a broadcastfeature.
Broadcast means packets are sent to all devices connected to theInternet. This lead to the congestion on network and packets are dropped 4) Packet loss:An IPV4 header contains afield called time to live (TTL). By this field the time of expiry is set whenthe packet / datagram does not reach the destination within that specific timethen the receiver has to request to the sender again to resend that datagram. 8This multiple sending of same packets and delay may lead to the packet loss.
Inparticular application like real time it cannot be tolerated.5) Data Priority In IPV4 it is not possibleto recognize the data being transmitted so high priority data cannot betransmitted on priority basis.Internet Protocol Version 6(IPV6)IPV6 is also known as nextgeneration of IP (IPng) which is the successor of IPV4 which is in use in todaythe Internet. IPV4 address example is 47CD:1234:4422:ACO2:0022:( 234; A456:0124)48CE:0000:0000:0000:0000:0000:A456:1245Address with a largenumber of successive 0s can be written 48CE:A456:1245The IPV6 packet format is Version Traffic Class Flow Label Pay Load Length Next Header Hope Limit Source Address Destination address Version field identifiesthe version of the protocolThe Traffic Class and flowlabel fields are used to ensure the quality of service.Pay load length shows thelength of the packet excluding packet headerThe next header has mergedthe options and protocol field in IPV4Hope limit counts thenumber of hopes a packet passesSourceAddress andDestinationAddress fields identify the source and destination address of thepacket.The concept of IPV6 wasput forwarded to overcome the limitation / shortcoming of IPV4 so the mainfeature for IPV6 are dismissed below 1) Address Space IPV6 uses 128 bit addressspace therefore the possible number of IPV6 address are 3.4 1038.
Theses addresses are enough to accommodate each and every day on thesurface of the earth truly uniquely. This expansion of IPV6’s address spaceTo make NAT not necessary To improve totalconnectivity To improve reliability To improve flexibility 2) Security In IPV6, Internet Protocolsecurity (IPsee) was integrated which was optional in IPV4 IPV6 offers three types ofAuto configuration Stateless Autoconfiguration IPV6 includes a plug andplay mechanism that facilitates the connection of equipment to the network. Thisis called stateless auto configuration. In stateless mechanism router willprovide the prefix from router advertisement3) IPV6 provides thefacility to facilitate the large number of hosts.4) Multicast facility In IPV4 multicastcapabilities were present but never routers support it and was optional but inIPv6, multicast is ………………..5) IPV6 also definedanother service called any cost besides uncast and multi cast 6) Some optional fieldwere removed from IPV4 and a few more are added in IPV6 7) Mobility is another keyfeature of IPV6 this feature enables hosts to ream around in differentgeographical area and remain connected with same IP address.
8) The header format ofIPV6 is simple which make packet handling more efficient 9) IPV6 allows fragmentationat end host instead of router IPv6 hosts are required either perform path MTOdiscovery and fragment packet before sending them out or only send packetswhich are larger than minimum MTU. Due to this feature processing at routerbecome easier.10) In IPV6 header, thereis a field called flow label which allow the Internet service providers toperform traffic engraining and quality of service etc. IPV6 Migration Issues andtechniqueMigration or transitionfrom IPV4 to IPV6 is not possible at one day due the reason that the Internetis too big and no centralized.
Before discussing the technique for transitionfrom IPV4 to IPV6 let discuss the issues that need to cared 1) In order to supportIPV6 many protocols like DHC, OSPF, RIP, BGP and other protocols need to beredesigned.2) To migrate from IPV4 toIPV6 the networks devices like switches, router and other device need toreplace by such device which can support IPV6 but which is costly or expensive 3) IPV6 has been lunchedbut till now it has not been tested properly so security may be a problem The techniques that can beused for transition from IPV4 to IPV6 are:1) Dual Stack In dual stack technique totransition from IPV4 to IPV6 both IPV4 and IPV6 protocol runs simultaneously ondevices in the network. It means to implement dual stack technique we have tocreate a stack that supports both protocols. Currently this technique is used asa deployment stately for network but there are many issues to be solved likeall routers need to be upgraded to IPV6 and dual management of IPV4 and IPV6routing tables2. Tunnelling In this mechanism andtechnique the existing IPV4 network can be used to carry IPV6 traffic and viceversa.
Tunnelling may be IPv6 over IPV4 or IPV4-over –IPV6 networks. Using thistechnique an IPV4 network user can communicate to an IPV4 network .Tunnellingmay be manual, Automatic and semi-automatic .In manual tunnelling the end pintof the tunnel must be configured manually.
The end point may either a router orhost In automatic tunnellingthe IPV4 address information is embedded in an IPV6 address.