Course Website with 3D Materials
Data communication and ISM
Open System Interconnection model (OSI)
The Open Systems Interconnection model (OSI model) is a conceptual model that describes the universal standard of communication functions of a telecommunication system or computing system, without any regard to the system's underlying internal technology and specific protocol suites.
Twisted-Pair Cable
There are two common types of twisted-pair cables:
UTP: Unshielded twisted pair
STP: Shielded twisted pair
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UTP is a cable with wires that are twisted together to reduce noise generated by an external source.
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STP is a twisted pair cable with an additional mesh shield that guards the cable against electromagnetic interference. Thus it can also eradicate a phenomenon called crosstalk. Because of the incorporation of the additional shield, the data transfer rate of STP is higher than UTP.
A straight through cable is a type of twisted pair cable that is used in local area networks to connect a computer to a network hub such as a router. This type of cable is also sometimes called a patch cable and is an alternative to wireless connections where one or more computers access a router through a wireless signal.
A crossover Ethernet cable is a type of Ethernet cable used to connect computing devices together directly. Unlike straight through cable, the RJ45 crossover cable uses two different wiring standards: one end uses the T568A wiring standard, and the other end uses the T568B wiring standard. The internal wiring of Ethernet crossover cables reverses the transmit and receive signals.
Hub, Bridge, Router and Switch
The Hub
An Ethernet hub, active hub, network hub, repeater hub, multiport repeater, or simply hub is a network hardware device for connecting multiple Ethernet devices together and making them act as a single network segment. It has multiple input/output (I/O) ports, in which a signal introduced at the input of any port appears at the output of every port except the original incoming. A hub works at the physical layer (layer 1) of the OSI model.
The Bridge
A network bridge is a computer networking device that creates a single, aggregate network from multiple communication networks or network segments. This function is called network bridging. Bridging is distinct from routing. Routing allows multiple networks to communicate independently and yet remain separate, whereas bridging connects two separate networks as if they were a single network. In the OSI model, bridging is performed in the data link layer (layer 2)
The Router
A router is a layer 3 or network layer device. It connects different networks together and sends data packets from one network to another. A router can be used both in LANs (Local Area Networks) and WANs (Wide Area Networks). It transfers data in the form of IP packets.
The Switch
A network switch (also called switching hub, bridging hub, and, by the IEEE, MAC bridge) is networking hardware that connects devices on a computer network by using packet switching to receive and forward data to the destination device.
Network hardware tools
The network hardware tools that are used in networking. Such as a wire stripper, wire crimper, multimeter, time domain reflectometer, optical time domain reflectometer, loopback adapter, cable tester, punch down tool, and tone generator.
Internet Path
The internet works through a massive global network of optical fiber cables. In this animation, you can see how data typically flows between the different levels of internet service providers in the modern internet. The optical fiber cables carry signals in the form of light. However, your laptop or mobile phone processes electrical signals.
Technology behind Mobile phone
For most of us, a mobile phone is a part of our lives, but I am sure your curious minds have always been struck by such questions as to how a mobile phone makes a call, and why there are different generations of mobile communications. Let's explore the technology behind mobile communications.
Telecommunication Base
In telecommunications, a base station is a fixed transceiver that is the main communication point for one or more wireless mobile client devices. A base station serves as a central connection point for a wireless device to communicate.