Abstract: Block chain is a technology which stores the information in decentralized way and distributing it evenly among the network of private computers. The major advantage of this system is you cannot corrupt the information, because it is backed up with several sources. Several small things such as intelligent thermostats, start lightnings and smart refrigerator, smart washing machine and smart beds are set to make life more convenient and pleasant. in traditional approach there are many security holes in a cloud based connections. the major problems are improper authentication weak password, and the neglect of transport layer security are also the serious problems