What is ip address, subnet mask and default gateway
- To uniquely identify a system in a network every system is given an unique address which is referred as IP address
- Execute ipconfig (ifconfig) from terminal
- From the above image we can understand ip address which is unique id given to the system in a network for communication
- Basic Network Rules
- A system (laptop/mobile) can communicate with any other system (laptop/mobile) in the same network
- Two Questions to be answered
- How does system know that other system is from same network?
- Google.com is not in my home network then how is it working?
How does system know that other system is from same network?
- IP Address: Ip address is combination of network id and host id
- The ipaddress in the above example was 192.168.0.198 What is network id in this & What is host id in this?
- Just by looking at ip we will not be able to tell network id and host id, we need subnet mask for that
- Lets try the below sample.
192.168.0 (255) => Network Id
198(0) => Host id
ip : 10.10.10.18
sm : 255.255.0.0
10.10 (255) => Network Id
10.18 (0) => Host id
- System will come to know if the other system is in same network if it has same network id
- Little bit more ip:
- The ip we have used is reffered as IPv4 which is a 32 bit number. Ip’s are represented as x.x.x.x where x => 8 bit number. x has minimum value of 0 and maximum value of 255
Google.com is not in my home network then how is it working?
- Lets ping google
- In networking based on rule two systems can communicate only if they are in same network.
- There is a networking component called as router. The responsibility of router is to forward packets from one network to other.
- Generally router ip address is stored as Default Gateway
- Your router forwards the packet to other network which forwards to other this happens till google.com is reached (hopping).
What are components of my home internet connection & its relavance
- Router: Router is used forward packets to the internet
- Modem: connects to the internet service providers network
- What happens if modem is down?
- Will we have network? Yes we will have network without internet access
- What will happen if router is down?
- We will have no network (Network will be down)
- Create AWS Account Refer Here
- Create one ec2 instance and delete it Refer Here
- Install necessary Softwares Refer Here