The Internet, as we know of it is based on request and reply mechanism, where a client (that could be a laptop, a tablet, a mobile phone etc) makes request to a centralized server, the server looks up into its database (if database is needed), processes the request, prepares a reply and sends it to the client again. An example could be, when we type ethereum.org, in our browser and hit enter, the browser sends request to a DNS server,saying “What IP is this name ethereum.org mapped to?” which returns the respective IP address of Ethereum’s server (near to our location). Our client device then uses this IP to send a request to Ethereim’s server to send its webpage to us. Upon receiving the request, Ethereum’s server sends us the appropriate web page. The system, as it is now, looks properly working. But, there is one problem. The DNS server and Ethereum’s server that are centralized servers. If they go down, the entire process can go down. Recently, a DDOS attack was executed on Dyn which is a centralized DNS service provider. AirBnB, Amazon and Netflix are some of the top names that were highly affect by this attack. The problem : a single point of failure.