According to United Nations survey the world population is likely to reach 7 billion by 2050 and around 70% of them will be living in cities sine around 50,000 people across the globe move from rural areas to urban areas every day. At the present trend of ICT penetration rate by 2020 more than 50 billion devices will be connected to web, hence IPv4 will not be able to assign Internet Protocol (IP) address to this exponentially growing networked society. In 2019 IPv6 is likely to replace the current IPv4 and to be established as standard Internet protocol. This paper is a comparative study of IPv4 and IPv6 and role of IPv6 in the future scenario of growing connected society.