Computer Networks
Computer Networks


- A computer network allows computers to interchange information. This networking happens with the use of a data link.

- Data link configurations include but are not limited to:
1) Simplex communications: The communication here is made in one direction only. For example commercial radio and baby monitors.
2) Half-duplex communications: The communication happens both ways, but not at the same time. So if side A communicates, transmissions must stop before side B communicates. An example of this would be a walkie-talkie.
3) Full-duplex communications (double-duplex): The two devices both communicate, and at the same time. For example, landline telephones and cell phones.

- The items used to connect devices to make a computer network are electric cables, optical fibers, and radio waves.

- Information is carried in packets through a computer network. Data is formatted into packets and once it reaches its destination its is put back together and reformed into the original content.

- Packets include two types of data: control information which is the data used to deliver to the specific destination, and the payload which is the actual content of the message being sent.

- Node: A point in a network where it can receive, create or store data. Nodes have the capability to recognize, take care of, and forward broadcasts to other nodes.

- Network structures have different layouts, some examples are:
1) Bus network: All nodes are connected to one cable referred to as the bus.
2) Star network: All nodes are connected to one specific node, and each node has its own cable.
3) Ring network: Each node is connected to two other nodes with a cable forming a ring.

- A network can be typified depending on the physical capacity, some of the different types are:
1) Personal Area Network (PAN): It involves the communication between a computer and other devices, belonging to one person. The reach of is most usually 10 meters.
2) Local Area Network (LAN): This is a network that connects computers and devices within a specific geographical area. For example, a home, school, or building.
3) Campus Area Network (CAN): This network connects different LANs. For example, in a university campus, this network would connect the LANs of different buildings.
4) Wide Area Network (WAN): A network that covers a large area like a city or country. A company that uses a WAN network would use it to connect the branches and the headquarter.


Questions

1) Can we expect to rely solely on wireless networks in the future?
2) The internet is a huge network, how can we break it?


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