Routing and Packet Forwarding

The history of the internet and Peer-to-Peer networks starts in the 60s with the ARPANET (Advanced Research Project Agency Network). Back then, when computers were expensive and linked to several terminals, the aim of ARPANET was to establish a continuous network inbetween mainframe computers in the U.S. Starting with only three computers in 1969, mainly universities were involved in establishing the ARPANET. The ARPANET became a network inbetween networks of mainframe computes and therefore was called inter-net. Today it became the internet which links millions of computers. For a long time nobody knew what use such a Wide Area Netwok (WAN) could have for the population. The internet was used for e-mails, newsgroups, exchange of scientific data and some special software, all in all services that were barely known in public. The spread of