IOSR Journal of Computer Engineering (IOSR-JCE) e-ISSN: 2278-0661,p-ISSN: 2278-8727, Volume 17, Issue 1, Ver. IV (Jan – Feb. 2015), PP 72-75 www.iosrjournals.org DOI: 10.9790/0661-17147275 ww.iosrjournals.org 72 | Page Performance Evaluation of IPv4 Vs Ipv6 and Tunnelling Techniques Using Optimized Network Engineering Tools (OPNET) Abass Mohamed Ahmed Kapashi Ahmed 1 , Dr. Amin Babiker A/Nabi Mustafa 2 Dr: Gasm Elseed Ibrahim 3 1,2, Faculty Of Engineering, Neelain University ,Khartoum -Sudan Abstract: Internet Protocol version 6 (IPv6) is the latest version of the Internet Protocol (IP). IPv6 is intended to replace IPv4, which is still widely used, in order to deal with the problem of IPv4 address exhaustion. In addition to evaluating the performance of IPv6, it is important to consider the interoperability between IPv4 and IPv6 networks, in addition to the migration process from IPv4 to IPv6. One way for IPv4 users to access IPv6 users/hosts is by encapsulating IPv6 packets within IPv4, in effect using IPv4 as a link layer for IPv6. This is known as tunnelling. The aim of this paper is to compare and evaluate the performance of IPv4, IPv6 and tunnelling (6to4) using OPNET 17.5. A computer simulation shows the theoretical comparison in terms of delay, throughput and packet loss. Keywords: Automatic tunnelling, Delay, IPv4, IPv6, Manual tunnelling, OPNET, Packet loss, Throughput I. Introduction A. Background Today hundreds of millions of users are interconnected by communication channels allowing them to communicate and to share information. These users and the devices that interconnect them are what constitute the Internet. The Internet is a network of networks with a myriad of computer devices, including smart phones, game consoles (handheld/stationary), IP televisions, tablet computers, laptop computers, desktop computers, palmtop Computers. B. IPv4 The IP layer of abstraction is mainly charged with delivering Internet Protocol (IP) packets from source to destination. In order to perform this task, the source and destination IP addresses are identified by unique fixed length addresses. In IPv4, a 32 bit numeric identifier was deemed sufficient when the Internet was created. However, as the Internet growth has been exponential it is clear that there is a need for a revision of the IPv4 addressing scheme. We will not delve deeply into the techniques that have been employed to delay IPv4 address exhaustion; instead we show the progression of events in order to better understand the proposed solutions. introduces class full network addressing architecture, the first classification of IP addresses. This scheme supported few individual networks and clearly could not support the growing Internet. C. IPv6 The described IP address space exhaustion mitigation techniques, each with their own draw backs. These techniques were only short-term solutions to delay exhaustion, while more tangible solutions were sought. In this section we look at a long-term solution, the next generation addressing scheme, IPv6. The steep growth of the Internet has determined the fate of the Internet Protocol. The Internet Protocol version 6 or IPv6 emerged amidst concerns about whether the Internet would adapt to increasing demands. IPv6 is now gaining momentum as the apocalyptic predictions concerning address exhaustion have been fulfilled. We start our study by identifying problematic areas in IPv4 and examining the solutions provided in IPv6. D. Tunnelling Techniques Tunnelling techniques can be used to deploy an IPv6 forwarding infrastructure while the overall IPv4 infrastructure is still the basis and either should not or cannot be modified or upgraded. Tunnelling is also called encapsulation. With encapsulation, one protocol (in our case, IPv6) is encapsulated in the header of another protocol (in our case, IPv4) and forwarded over the infrastructure of the second protocol (IPv4). Transition mechanisms that allow IPv6 hosts to communicate via intervening IPv4 networks are based on a technique known as tunnelling or software, which ensures there is no disruption to the end-to-end IP communications model. To accommodate different administrative needs, two types of tunnelling techniques are available: configured (static) and automatic (dynamic).