We all use all our devices and gadgets seamlessly at our home and offices. But, have you ever thought how these devices are connected to the network wirelessly? what is the technology that makes it work so easily? There is device called as router which enables you to connect your devices and gadgets to Internet either in wired or wireless form. We have read how does internet work, this article will add more to that series. There are several technologies which makes Internet easier to work and use.
Router is a network device which allows a different type of devices to connect to Internet. It work as a gateway in between your local network and the internet. All the network traffic generated has to pass through the router. Main job of router is to route the traffic to proper destination, it works as a traffic police man, that is why it is called as Router. A device can be connected to a router in wired or wireless manner.
How Does Router Work
Working of a router is very easy to understand. As I mentioned earlier router works much similar to a traffic police man. Let’s say 5 devices are connected to the router at a same time. Does the router provide the service to all the device at same instance of time? No, the router can provide service to only one device at a time. But it does the work so fast, it feels like all the devices are served simultaneously.
Every device connected to the router has a IP address assigned to it. You can read more about IP address here. This is a local network address and is not visible to outside network. Your network’s IP address is assigned to your router. As we mentioned earlier, all the network request from local network passes through the router.
Router has a routing table in which it keeps track of source and destination IP addresses of every network packet.
We will break down the working of a router in following logical steps. Consider three devices are connected to the router device A, device B and device C.
Device A sends a network request to the router
When device A tries to access a website say “thehappylearning.com”, the request is passed to the router. The request has source and destination IP address. In our case the source address would be our local network address say “192.0.0.1” and the destination address would be something else.
Router Receives The Request From Device A
Now, when router receives the request from the device A. Router scans the packet for source and destination IP addresses. Router makes an entry of the packet and also makes the entry of source and destination address into the routing table. Then, router replaces the source address of the packet by the network address or its own IP address (network IP address and router’s IP address is same), and forwards the packet to the destination address. And then waits for the reply from the destination server.
Router Gets Back The Reply From Destination Server
Our router gets back the reply from “thehappylearning.com” server. Now, our router has an entry of the IP address of the “thehappylearning.com” server against our device A’s IP address. At this time the source address in the network packet is the address of “thehappylearning.com” and the destination address would be our network or router’s IP address. Router identifies that Device A is waiting for the reply.
Router Send Back Reply To Device A
Again router scans the network packet and replaces the destination address with our local device’s IP address. Then the packet reaches the Device A. Finally, device A got the reply.
All this process happens so fast that we don’t feel that something like this is happening at the end of our router.
Responsibilities Of Router
- Routing of network traffic : Main work of router is to route the network traffic. Router achieves this with the help of routing table. Routing table keeps the track of all the incoming and outgoing requests.
- Prioritize the network request : Router often prioritizes the networks requests. There are some requests which have high priority over other. Like a webpage has a priority over the video.
- Can work as a security provider : Router can be configures to allow only certain traffic. That means, we can restrict the packets passing through the router. This be done by applying certain filters at the router end.
- Work as a default gateway : Router works as a default gateway and allows every single bit of network traffic through it. It ensures that all the traffic passes through and not a single packet gets dropped.
This was pretty much non-technical about the router. We tried to explain this in very simple language, so that every single of you should understand. If you still have any doubts feel free to ask us in the comment section below.