P2P was used to share files earlier and now it is used to transmit voice over it. Skype is a state of the art IP based telephony. When a computer is connected to the network the processing power of that network is increased and the bandwidth is also increased. This is taken advantage in skype. There is no special configuration needed for skype to work behind firewalls. The calls are encrypted and hence there is no security risk. Usually a centralized directory is used to connect the users by logging each user. If the number of users is increased in the order of millions the cost of a centralized directory is also very large. Understand this, skype uses a decentralization technique and uses the network efficiently to connect the resources together. A Global Index technology is used by skype where there are many super nodes that connect to the nodes down the line. The calls are routed through an effective path which increases the quality of the call.
Technorati Tags: Internet Telephony, Chat, Conferencing, VOiP