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The Information Channel

Note: in order to run the simulation referred to in this slide, go here, to the Java Applet version. You will be directed to download the latest version of the Java plug-in.

For the moment, we suppress what happens at the ends and focus on the information channel in the middle. An information channel may represent physical wires, radio broadcast, a beam of light, or some other system used for transmitting information. For the moment, we will consider the simplest representation of a channel, one without noise. This means that the channel output equals the channel input.

The defining characteristic of a channel is that the message transmitted is not "hard coded" into the channel when it is constructed. Rather, a message is chosen from a set of possible messages and then transmitted. Furthermore, an information channel does not act instantaneously. Each symbol transmitted requires a certain duration of time. This places a limit on the speed at which a channel can transmit information, which we will call the channel capacity.

The most familiar type of discrete channel is the simple binary channel, represented to the left. This channel transmits a series of 0's and 1's between the transmitter and receiver. Press "Go" repeatedly, and this will happen. The receiver will write the symbols that he is sent in the received code variable. Notice that one symbol is sent in every time step.

The size of each agent corresponds to the number of symbols they process. Thus, the agents start with no size and approach the same size over time.

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