🌐 Internet Simulator

Do Now (In Classroom)

Open the code.org invitation and join our group.

Signals & Protocols

Yesterday you made a device a set of rules. What you were developing is called a protocol.

Protocol - A set of rules governing the exchange or transmission of data between devices.

Bit - a single binary digit

We’re going to use the Internet Simulator to send 2-bit messages.

Login and see what you can figure out. Click all the buttons, try typing, see what happens.

Internet Simulator

Neither partner is β€œsending” or receiving anything. You can always set or see the state of the wire.

Challenge: figure out a protocol to send messages back and forth. Your goal should be to develop a protocl that sends messages as quickly as possible. This is what’s called a bitrate.

Bitrate - the number of bits that are conveyed or processed per unit of time. e.g. 8 bits/sec.


A binary message consisting of four bits was sent to you by a friend. The message was supposed to be ABAB. Unfortunately, your friend set the bit on the wire once every 2 seconds, but you read the wire once every second.

Assuming that the first bit was sent and read at the same time, what message did you receive instead?