VPN

Virtual Private Network:

Telephone Network                                                                 Internet network
    
If something fails in middle on telephone network then there is no chance of connecting itSo Us military developed internet network with thousand of routers in middle so if some thing fails it will automatically chooses other path

If a hacker enters into any router he can grab all the info. So the need of VPN arrises
             
Basically works on Tunneling protocol                Changes tunnel if it feels any attacks

A client server technology
closes tunnel and recreates it when it feels something is happened in middle

Necessary things to have for VPN

Good upload speed
Routers must allow VPN pass through(all new routers support)
Good wiring since bad wiring causes packet loss which vpn thinks hacker and keeps on changing tunnel

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