يررسي مشكلات وچالش هاي پيش روي همزيستي شبكه هاي IPv4و IPv6 و ارزيابي عملكرد راهكارهاي ارائه شده

چكيده انگليسي :

The Investigation of IPv6 and IPv4 Coexistence Challenges and Evaluate of Presented Solutions for this Issue Seyedali Mirkhandouzy Sa mirkhandouzy@ec iut ac ir March 3 2012 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Dr Hossein Saidi hsaidi@cc iut ac ir Dr Massoud Reza Hashemi hashemim@cc iut ac irAbstractInternet which plays an important role in the communication all across the world has grown widely as a result ofextensive efforts in sharing information and expansion of widespread applications Cisco reported that the number ofconnected portable devices to the internet will exceed the world population in 2012 The latest report about globaldata communication via portable devices that has been released by Cisco predicts that more than 10 billion portabledevices such as tablets and cell phones will be connected to the internet all over the world by 2016 Development of voice and video communications over the internet advent of IP based mobile expansion ofwireless internet increase in the number of users and in general has increased the demand for IP addresses But 32bit address space of current protocol of internet has constrained IPv4 ability in allocating addresses to users Although some mechanisms such as NAT and CIDR may expand the IPv4 life for a while and delay the IPv4 adressexhaustion but address space limitations and some intrinsic problems of IPv4 header remain as before Thereforetransition to the new version of the IP protocol IPv6 for solving the limited address space and other problems ofIPv4 protocol is inevitable IPv6 stands for Internet protocol version 6 This protocol has been designed by IETFto solve many problems of current and previous versions of the protocol IPv6 as a substitution for IPv4 has solvedthe problem of IPv4 address space by assigning 128 bits for internet addresses Furthermore it has added newfeatures such as mobility security and automatic configuration to IP based networks However it should be notedthat we cannot consider a specific day for migration of all networks to IPv6 since IPv4 networks and services havebeen spread widely all over the world In addition most of the organizations have such a deep dependency to theInternet which they cannot tolerate the internet interrupt even for single day So it is necessary to consider a periodof time for network migration from current IPv4 to IPv6 which is called the coexistence time Three main mechanisms have been proposed in the literature for the transition from current networks to IPv6 Thesemechanisms are tunneling IPv6 packets in IPv4 packets and vice versa Dual Stack mechanism and addresstranslation between these two protocols To provide a smooth transition while maintaining the current equipment upgrades of network should be done based on the current IPv4 network IPv6 should be implemented in a smallerscale and then it should gradually extended to larger environments In this thesis we investigate IPv6 protocols its features and its facing challenges An experimental test bed based onIsfahan University of Technology network is implemented using OPNET software Different coexistencemechanisms of the two protocols have been simulated and compared using this test bed in various conditions AnAlysis of the results and We also simulate different suggested scenarios to determine which mechanism in whichconditions would be better Finally based on the simulation results and review of the advantages or disadvantages ofeach mechanism a comparative analysis of the results is presented

ميرخاندوزي، علي

يررسي مشكلات وچالش هاي پيش روي همزيستي شبكه هاي IPv4و IPv6 و ارزيابي عملكرد راهكارهاي ارائه شده

پروتكلIPV6 , تونل زدن , مسيرياب , كپسوله كردن بسته ها