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Modem vs Gateway vs Router

Modem — process the signal from ISP and interfaces to the home network .

https://www.youtube.com/watch?v=Ea4rMYM_Mz8

Modem:

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  • Not intlligent
  • Not programmed
  • Not data protection
  • Do not has a firewall

Router — create a local network with each device has uniq ip adds.

  • Intelligent device
  • Every digital router contains a modem
  • Router provides firewall func
  • Tunel options provides (IPsec, GRE , PPTP ,OpenVPN tunes options)
  • May include IO functionality.

Gateway — they provide protocol translation (zigbee, mudbus , celluar, PCI , RS-232 ….)

  • Less traffic control
  • Simple to configure
  • I/O options
  • Gateway is a protocol translator .

Switch — one port to many. But don’t assign different ip.

Network bridge — link devices together linear.

Network hub — dose not analyze traffic, just broadcast anything to every port .

Modem — Translates different form of data (analog to digital, digital to analog)

Gateway — Translates same data for different protocols

Router — includes a modem sometimes (wires to wifi for example)

RF modem

调制解调器(英语:Modem,modulator-demodulator的英文缩写)是一个将数字信号调变模拟信号上进行传输,并解调收到的模拟信号以得到数字信号的电子设备

Модем (ағылш. modem, modulator-demodulator) — сандық сигналдарды аналогтық сигналдарға айналдыратын және керісінше амал жасайтын электрондық құрылғы.

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Modem — modulator-demodulator

Modulations

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Digital modulation is more immune to noise .

Binary digital modulation ;

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