Networking Devices
In earlier blogs we discussed about how the client server system works, but the main thing that carries all that is our internet connection. The resolving of DNS through finding the ip address, or sending or recieving a http response/request, all this is done with help of an internet connection.
There are many devices around us which help us reach the internet or in better words , they let us connect our devices to the internet. One such most commonly used device is our modem. It acts like a direction sign for the internet which help it reach to us by directing it.
Internet to Devices
The flow of internet is like Internet → Modem → Router → Switch → Devices flow
Internet
Its the network provided by our Internet Service Provider(ISP) like jio,airtel etc. This kind of network is not accessible by our devices. This is the nework which they get through connectiong to other global networks using fiber optics cables, under land and ocean at the exchange stations.
Internet is formed by connecting many of these networks together.
Modem
Its the first device to directly contact the ISP. It directly access the internet provided by the ISP and converts it to the type of data that is accessible by our devices.
Router
Once our data is passed through modem it reaches our Router which further directs it according to requirement and manages the traffic. Its the device that provides wifi access to our computer, mobile and other devices which we use at our home or office locally.
Switches
In workplaces,offices people prefer wired connections, due to stabilty and speed of the connections. At places like these switches are used to increase the limited number of switches in a router. It helps connect much more wired devices to the router.
Devices
The final place where the internet reaches is our devices where its required for our work. These devices access internet and send the relevant requests and responses in form of http request and the data travels back in the same way it orignally came.
All the layers in this system have a dependency on each other and even failing of one causes our internet connection to go down.
Firewall:
For law and orderm, there is always a enforcer needed along with a set of rules. Similar is for the case of internet , as internet is an open network anything can be sent or recieved by anyone, but so that doesnt happen firewalls are in place to keep these things away.
It prevents the unwanted/malicious packetes entry.
It allows recieving from the server that has been initially connected and block any other incoming data packets or request
It helps in ignoring malware and random traffic on the internet
It works like a guard for our instance of connection to the internet, by keeping only the safe traffic in.
Local Area Network (LAN)
So as we talked about the how internet reaches our home, workplaces etc.. A particular thing always come to mention in with concurrent to network in a place where multiple people work and that is LAN. It helps conect multiple devices in a local area and help them talk to each other directly, without using the internet .
Now comes the question how does it do that???
So, the LAN does that by creating a private ip address which is connected wirelessly through a switch or wifi. This network uses the router only when the traffic needs to leave the LAN.
Device searches for a DHCP server
Router replies with ip address and dns server along with other required information
Device accepts and configures itself
Now the device is connected to LAN
Every device knows each other ip and registered on the LAN network
Load Balancer
As we have talked about multiple devices on one network , there must be a system which decides which one goes first or there will always be a conflict. A system a was designed to prevent this conflict along with preventing overloads, improving speeds, increasing reliability.
It checks the current server load and health and choose the server based on many optimised algorithms to decide the next server. Also ensuring the working continously and checking the servers is also its responsibility, but to manage all that it also has to be fast, accessable to the ip and have understand of http.
This covers the Physical working of our network, it may be different from the tech stuff like DNS, http but its essential for them to work together as one. More related blogs coming soon
