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Internet Communication | TCP/IP, Modem, Switch, Router... | Page 1



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Your Computer --->Data Stream [0000100111]---> Wireless Card / Modem ---> Switch --->





Your computer can only understand the machine language which is usually a string of 0s and 1s. Whatever files like docx, image file, etc. all are nothing but a combination of 0's and 1's. Similarly, all computer commands are also in binary code to execute programs inside the CPU. Whenever you are trying to send a file to another computer it is modulated with high-frequency carrier waves for proper transmission and another benefit. if you want to read further about the requirement of modulation, then click here. 

Your computer contains a Wireless card or an inbuilt modem inside. it converts the digital commuter data into analog data by using various modulation techniques. Here, transforming your digital data into an analog one is required for many reasons as follows

  • transmission mediums like wireless channels, copper cables, optical fiber, etc., - all are analog in nature. You can't transmit a digital signal thru an analog medium. why?
  • Modulation is required to multiplex the data.
Now, come to the swathing or switch. You know previously we were using HUBs to broadcast router signals to all computers connected to the same router. If that data's destination address is matched with any computer then it is received by that computer; otherwise, it is discarded. We observed a lot of collisions and bandwidth inefficiency in HUBs. 
Nowadays, we use switches instead of HUBs. Here each device connected to the router is connected through different switches. Switches are usually termed ports (of the router). It is bandwidth efficient as compared to HUBs.     



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