  Currently IPv6 is extremely popular with companies, organizations and
Internet service providers (ISP) due to the limitations of IPv4. In order to
prevent an abrupt change from IPv4 to IPv6, three mechanisms will be used to
provide a smooth transition from IPv4 to IPv6 with minimum effect on the
network. These mechanisms are Dual-Stack, Tunnel and Translation. This research
will shed the light on IPv4 and IPv6 and assess the automatic and manual
transition strategies of the IPv6 by comparing their performances in order to
show how the transition strategy affects network behaviour. The experiment will
be executed using OPNET Modeler that simulates a network containing a Wide Area
Network (WAN), a Local Area Network (LAN), hosts and servers. The results will
be presented in graphs and tables, with further explanation. The experiment
will use different measurements such as throughput, latency (delay), queuing
delay, and TCP delay.
