Last century brought us the dawn of the Information age and in this century information technology continues to rapidly enhance in all aspects of personal, social and business activities. Times are changing, technology is changing, and so do the demands and the expectations of its users. Undoubtedly, the Internet is playing a vital role by providing a global information superhighway. Internet Protocol (IP) v4 is the standard for the design and interconnection of networks today; however IPv4 has limitations that hinder growth of the Internet. IPv6 is the solution and it has two-fold advantage - it addresses inherent problems in the earlier version protocol, and it offers new opportunities that can enhance communication experiences of users beyond current scope. However, IPv6 has larger data overhead than its counterpart, which hints network performance issues. In this paper, performance of four software routers with IPv4 and IPv6 has been evaluated in a test bed setup. It is seen that throughput, jitter and delay differ between the operating systems and IP versions when all else remains constant in the test bed.