“With the growth of Internet, will IPv4 survive?” Note: Please focus on security, quality of service, and migration method.
Introduction
Humans are social who depend on the interaction with others for daily needs. Throughout human history, people some of them with few exceptions, have expended on the structure of various community networks for carrier, safety, food and companionship. Actually, people have been networked for a very long time. The ways in which humans interact are constantly changing. For this time being, sounds and gestures were all humans used to communicate is now replaced by the Internet which allows people share all types of communication such as documents, pictures, sound and video with billions of people near and far using computers. For the students and educational purposes the internet is widely used to gather information so as to do the research or add to the knowledge of any sort of subject they have. Even the business personals and the professions like lecturers, engineers doctors need to access the internet to filter the necessary information for their use. The internet is therefore the largest encyclopedia for everyone, in all age categories. Besides, not to forget internet is useful in providing with most of the fun these days such as games, social network service, instant messaging, networking conferences, video sharing or the online movies, songs, dramas and quizzes. In that, internet has provided people with a great opportunity to eradicate the boredom from their lives. What is internet actually? Basically, internet is a combination of networks connected to each other. Internet becomes the world’s largest network as it exist such a huge network of several different interlinked networks relating to the business, government, academic, and even smaller domestic networks Therefore, internet is known as the network of all the other networks. These networks enable the internet to be used for various important functions which include the several means of communications like the file transfer, the online chat and even the sharing of the documents and web sites on the WWW, or the World Wide Web. Since, it is a network of the interlinked computer networking world wide, so it is accessible to public. These interconnected computers work by transmitting data through a special type of packet switching which is known as the IP or the internet protocol.

Internet Protocol (IP) is the primary network protocol used on the Internet. It is developed in the 1970s. IP is commonly used together with the Transport Control Protocol (TCP) and referred to interchangeably as TCP/IP on the Internet and other networks. The Internet Protocol is responsible for addressing hosts and routing packets from a source host to the destination host across one or more IP networks. For this purpose, the Internet Protocol defines an addressing system that has two functions which are identifying hosts and providing a logical location service.
IP supports unique addressing for computers on a network. For this time being, most networks use the IPv4 standard that features IP addresses four bytes (32 bits) in length. Currently, people are using IPv4. IPv4 is stands for Internet Protocol Version 4 address. The newer Internet Protocol version 6 (IPv6) standard features addresses 16 bytes (128 bits) in length. Internet Protocol Version 4 (IPv4) is the dominant protocol of the internet. Yet, the successor is Internet Protocol Version 6 (IPv6) which is increasing in use starting Jun 2012 where it is start to launch in certain country.
Internet Protocol version 4 (IPv4) is the fourth revision in the development of the Internet Protocol (IP) and the first version of the protocol to be widely deployed. Together with IPv6, it is at the core of standards-based internetworking methods of the Internet. As of 2012, IPv4 is still the most widely deployed Internet Layer protocol. Furthermore, the Internet Assigned Numbers Authority (IANA) organizes IPv4 addresses into classes. The number of hosts that a network has determines the class of addresses that is required. IANA has named the IPv4 address classes from Class A through Class E. The current system which is IPv4 only supports about 4 billion individual IPv4 addresses.

Body As the internet become larger and largest worldwide, while 4.3 billion addresses might seem more and more, the Internet was going to exceed the number of devices by the end of 2012. Every personal computer, notebook, PDA, smart phone and handheld (Blackberry or Samsung), every tablet like iPad, or Samsung Galaxy Tab, printer, or even play station require an IP address. As a result, there are not enough IPv4 addresses for all these devices.
Let's say, we know that one of the uses of IPv4 is to provide addresses. With rapid growth of the internet user, many devices duplicate the addresses to support massive user at the same time. In that case, many users will have same IP address which is not in the same network. So, the IPv6 is the solution for this. IPv6 can be used like MAC. Meaning that, every device has one IP. So, all the devices will be uniquely identified. However, in theory, IPv4 has 32 bit. 2 to the power 32 will give 4 294 967 296 possible addresses. Furthermore, IPv6 has 128 bits which provide (2 to the power 128) 79 228 162 514 264 337 593 543 950 336 possible addresses. To conclude all these things, IPv4 and IPv6 still will be used in the future because if one of the architecture is not in used, it means that we just reduce some connectivity in the network.
Internet Protocol version 6 (IPv6) is currently being rolled out across the globe, and it is enlarged addressing system that will fix the limitation of IPv4. IPv6 uses 128 bits instead of 32 bits for its addresses, creating 3.4 x 10^38 possible addresses that is a trillion-trillion-trillion an impossibly large number. These trillions of new IPv6 addresses will meet the internet demand for the foreseeable future. Thus, the IPv4 tend to not survive with the existence of IPv6.
Security
Now, let’s explore the reason why IPv6 is concern now in term of security. It has been said that IPv6 supports improved security because the specifications mandate the inclusion of the IP Security (IPsec) suite of protocols in products. For more information, IPsec (Internet Protocol Security) is a framework for a set of protocols for security at the network or packet processing layer of network communication. In IPv4, including IPsec is optional, but it is commonly available. Because the IPsec protocol suite is designed to be indifferent to IP versions, the technology works generally the same way in both IPv4 and IPv6. In this way, the benefits of using IPsec are similar in either environment.
The increased address space provided by IPv6 does eliminate the need to use NAT (Network Address Translation) devices, which are pervasive in many IPv4 networks. Broadly speaking, security is harder to deploy and troubleshoot when NATs are present in a network as they disrupt IP layer traceability and therefore security audit trails. In addition, the address rewriting that NAT performs is considered by some security protocols to be a security violation. Thus, with the increased address space eliminating the need to use NATs, IPv6 potentially facilitates deployment of end-to-end security.
As IPv6 is still new and the percentage of country have migrated from IPv4 to IPv6 is still less, a lot of the IPv6 security issues reported today have to do with vulnerabilities in individual products, not the IPv6 protocol. IPv4 is widely deployed and individual IPv4 products have gone through the recurring cycle of discovering and fixing security vulnerabilities and other bugs. Because IPv6 products are comparatively new, they have not benefited from similar experience. Consequently, security vulnerabilities in IPv6 products will need to be discovered and repaired, just like for other products.
As the world is going to use IPv6, the operational practices built up over many years for IPv4 networks will have to be adapted for IPv6. New practices will need to be developed for the dual stack IPv4 and IPv6 environment. This will be accelerated as more network operators deploy IPv6 and continue to exchange information about experience and best practices through established operators groups, the IETF Operations area, and other forums.
Overall, maintaining network security will continue to be a challenging undertaking in both IPv4 and IPv6 contexts. Neither protocol provides a simple solution to the complexities associated with securing networks. Like with IPv4, network operators should become educated on IPv6 security practices and keep up-to-date with developments as they plan for and deploy IPv6.
For now, the conventional method for networks and websites to allow access to both IPv4 and IPv6 protocols is dual stacking, however, this act of encompassing makes the networks more complex, and less secure. Unfortunately, the future of internet protocols will continue to look gloomy in terms of security. IPv6 has been around for a while, but the motivation for users to switch over from IPv4 has not been readily apparent because most of them are unaware of any of the advantages beyond those of moving on after the exhaustion of IPv4 addresses. Service providers and web-based companies are not under pressure to switch completely over to the new protocols either.
Of course, being older, IPv4 holds a majority of users, and without incentives, pressure or bans, the less secure IPv4 will prevail nearly indefinitely, forcing dual-stacking, and its inherent complexity. Further, until IPv4 is almost completely exhausted, new IPv4 addresses will continue to be assigned for a while, including those behind Network Address Translation (NAT), and its allotment of multiple private IP addresses to a single IP.
Quality of service
Conceptually, Quality of Service (QoS) relates to applications. For example, to guarantee high quality for phone calls established over IP, VoIP packets get higher priority compared to other traffics types. This means that QoS policies should be independent of IP version and should depend exclusively on application types. Thus, in a dual-stack network, the same priority is assigned to the packets of a given application independent of the IP version it runs over. However, for those very specific conditions that require one IP version to be privileged over the other, it is possible to assign different priorities based on IP version.
There are a lot of speculations saying that IPv6 offers better QoS than IPv4? This is mainly driven by the presence of a 20-bit field named Flow Label in the main IPv6 header, a field that does not exist in IPv4. The Flow Label field, as specified in RFC 2460 and RFC 3697, is used by a source to label packets of the same flow. Its guarantees that the information carried has an end-to-end, meaning that its value cannot be modified by intermediate systems. Although some interesting proposals do exist for the use of the Flow Label field. The field is currently unused and may not have practical value in the overall Internet where no definition of Flow Label value has been published or agreed upon by service providers. However, these 20 bits in the main IP header are very precious real estate, so forms of Flow Label usage will surely be developed in the future.
IPv6 QoS is neither better nor worse than IPv4 QoS. It follows the same architectural models and faces the same inherent challenges. However, the presence of the 20-bit Flow Label field in the IPv6 header is not enough to justify the claim of better QoS

Migration method
There are many techniques that enable network administrators to migrate their network from IPv4 to IPv6 without making any interruptions for the operation of the network. Firstly, in terms of dual stack routing, both IPv4 and IPv6 are running on the router simultaneously. Assuming that, both IPv4 and IPv6 devices will be able to work on your network. Thus, the Network administrator may gradually increase the number of IPv6 devices until he has a pure IPv6 network in a particular place or organization.
In addition, based on Cisco, by tunnelling, IPv6 packets are encapsulated into IPv4 packets in order to make IPv6 devices able work in an IPv4 network unless protected by deep packet inspection, because this could provide another risk. Such IPv6 security issues will need to be addressed, especially when many customers will still be on legacy IPv4 networks while others will have transitioned to IPv6. There are many types of tunneling such as “6 to 4 tunneling”, “Teredo tunneling” and “ISATAP tunneling”.
Also, Cisco saying that proxying and translation is other method of migration where the device is used that can translate between IPv4 and IPv6 to work as the translator agent between IPv4 devices and IPv6 devices. This process of this device is the same as NATting but the NATting here is between IPv4 and IPv6.
What does it mean to be IPv6 ready in an organization? It means spending money, including training network staff to handle IPv6 configuration and troubleshooting, plus modifying applications that use IP addresses. If most of the contacts still have IPv4 addresses or are happy with NAT, this won’t provide immediate return on investment.
After recognizing the return on investment might not be immediate, a plan needs to be developed taking key migration considerations into account. Firstly, security policies need to be revised. While IPv4 security issues are well documented, IPv6 remains largely unexplored. So, we have to take into consideration in term of security if we want to migrate IPv4 to IPv6. In this case, firewalls will need to be updated to recognise both IPv4 and IPv6 because a firewall that does not recognise IPv6 addresses could simply pass such packets blindly through.
Secondly, application compatibility needs to be verified. This is because not all existing applications are IPv6 compliant or reliable and definitely upgrades may be required to avoid any incompatibility. The network management systems (NMS) will need to be upgraded for IPv6, where the address fields are larger, the databases bigger and both IPv4 and IPv6 devices will be shown in the user interface. If the NMS is not ready for IPv6 it will need to be replaced
Lastly, we need to test the service of IPv6 for compatibility. Nevertheless, IPv6 compatibility in networking equipment often comes with added risks. Unlike IPv4, several IPv6 implementations are still to be optimized, and they may not have been used long enough for their reliability to be confirmed.
Managing the transition to IPv6 is a complex task and therefore prone to human error unless supported by automation. The right automated network management system will not only address NMS issues, but also greatly reduce the impact of the other costs by reducing problems, simplifying and making network management more transparent. Migrating from IPv4 to IPv6 in an instant is impossible because of the huge size of the Internet and of the great number of IPv4 users. Moreover, many organizations are becoming more and more dependent on the Internet for their daily work, and they therefore cannot tolerate downtime for the replacement of the IP protocol. As a result, there will not be one special day on which IPv4 will be turned off and IPv6 turned on because the two protocols can coexist without any problems. The migration from IPv4 to IPv6 must be implemented node by node by using auto configuration procedures to eliminate the need to configure IPv6 hosts manually. This way, users can immediately benefit from the many advantages of IPv6 while maintaining the possibility of communicating with IPv4 users or peripherals. Consequently, there is no reason to delay updating to IPv6.

Conclusion
As discussed in the previously, the IPv4 address space cannot sustain the Internet’s growth as well as in terms of security and quality of service. While, in order to migrate to IPv6 is not an easy way because it takes time to change it at all. What can I say that is for any long-term perspective, IPv6 becomes a natural choice. Moreover, as the resources become limited and getting less, the IPv4 address space will be exhausted one day. IPv6 will pick up where IPv4 left off and it will plumb the Internet for a long period of time to accommodate a very large number of devices that we can say that is in cloud computing.
As a conclusion, the IPv4 address space cannot sustain the growing number of Internet users and the many new ways in which the Internet is facilitating today’s communications. This evolution was not envisioned by the initial developers of the TCP/IP protocol suite. The only real option to address the growth pressures faced by IP is IPv6. Although IPv6, similar to IPv4, is a live and evolving protocol, it has already reached the level of maturity needed for safe, large-scale deployments. In recognition of a need for IPv6, organizations worldwide are already deploying it or aggressively planning its deployment in the foreseeable future.

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