A mental model of the Internet

The most important change in the way I started to view the Internet was that I ceased to imagine it like some form of telephone network where computers connected to each other in order to communicate. I'd always viewed the Internet as a complex arrangement of wires and switching mechanisms. I was shocked to find it wasn't like this at at. In its place I now had a "name space", where the names were like islands in a vast ocean of water with no connection between them other than the currents in the water.

For these islands to communicate, they had to break all their messages up into bits, put each bit in a bottle and throw the bottles into the ocean to let the currents take them to their destination. This was the key break through. It wasn't about making connections with other computers: the moment a message or any part of a message is sent it becomes stateless and the sender loses all contact with it and there is no contact at all with the intended recipient or any of the computers through which the messages are passed.

Note: The way these stateless messages get passed around from computer to computer on their way to their destinations is both ingenious and remarkably simple. To limit the effect of a breakdown the messages are all sent as small data packets (about 1,000 characters long i.e., 1 kilobyte). All the data packets are sent to a main highway (the backbone of the Internet). This consists a number of heavy duty computers — known as routers — that pass all Internet messages between then.

They each carry continuously updated maps of the Internet that tell them the location of every computer currently on line. This allows them to be able to work out the best way to send the packets to be able to reach their destination. However they don't just send a packet the physically shortest route, they try to send it in the shortest time which might mean routing it around heavily congested parts of the Internet.

Each data packet, passing through a router, contains a record of its travels through the network together with the times at which it reached each computer it passes through. This allows routers to work out all the current transmission speeds throughout the entire network and calculate the probable fastest routes to pass the packets on towards their destinations. Routers pass these data packets to each other until they reach the locality of the destination computer. Then it is passed into a local network to be passed on to the computer the packet is addressed to. This destination computer will wait until all the packets of a particular message arrive and then put them all together to recreate the original message as it was sent by the sender.

Routers are constantly communicating with each other, updating each other about maps and transmission speeds, working as a kind of team to ensure all packets of data get to their destination in the shortest time possible. They correspond with each other every three to 30 seconds and if a communication goes over the thirty second limit the receiving router assumes the late sender is out of action and tells all the other routers to route messages around it.

Once it dawns upon you that all data packets and messages are stateless — quite isolated and independent of sender and receiver while they are in transit — you can look at the environment of the Internet in a completely different way. Not only are the data packets and messages stateless, so are the senders and receivers

A sender can pop up anywhere on the Internet to send a message. It doesn't matter where they are physically located. Similarly with receivers, they can change their position in this name space at any time and still receive messages that are addressed to them. This can give rise to a phenomenon that it impossible to create in the world of bricks and mortar, a virtual entity.

A virtual entity is an entity that has no fixed form or shape. It is created out of components that are connected together only by the imagination. Such things are impossible in the physical world. Imagine creating a perfect partner for yourself, choosing all the best features and body parts from a host of film and television personalities and putting them all together to create the perfect person. Imagine being able to give this virtual partner the personality of the nicest person you know and the intelligence of the cleverest.