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Computer Networks. First Quarter Marking Period Review. Signals. Digital Signals. Computer systems use binary code to communicate. Ones and zeros are strung together to form instructions to the computer . Computer networks use electric pulses across wire to communicate.
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Computer Networks First Quarter Marking Period Review
Digital Signals • Computer systems use binary code to communicate. Ones and zeros are strung together to form instructions to the computer. • Computer networks use electric pulses across wire to communicate. • The pulses travel with less static and interference than analog signals, which tend to degrade more across longer distances.
Packet-Switching • Information is broken down into packets and sent across the Internet via different routes • Each packet is labeled with sending computer and destination computer addresses • Network switches and routers use these addresses to forward the packets to their destination • By sending packets through many computers instead of one direct route, computers can be added to the network and if one crashes the packets can go a different way • The packages have a specific order and are reassembled in that order when they arrive at the destination
IP Protocol • A protocol is a set of rules that governs how something works • Internet Protocol (IP) breaks data into packets and puts them in the correct order. • All IP packets have a header that contains information such as the total number of packets and the order they should go in. • The actual data in the packet is sometimes called the payload.
TCP Protocol • Transmission Control Protocol selects the best route for a packet to travel and takes care of any problems along the way. • TCP can request re-sending of packets, reroute a packet to avoid problems, and helps minimize network congestion.
TCP/IP Packet • This is what a packet might look like:
Diagram • You will be create a diagram of a packet switching network showing how information is broken into packets that travel across different routes to get to their destination. • Include the following in your diagram: source and destination computers; several routers; two packets going different routes with arrows showing direction they are traveling; a description of what IP and TCP are doing.