The Network layer is the process of routing and forwarding data packets across different networks.
This layer ensures that data is transmitted efficiently and securely between devices. Beginners should focus on understanding how the Network layer enables communication between different networks, laying the groundwork for secure data transmission.
Remember, the Network Layer ensures smooth data flow, like a well-regulated traffic system
IP (Internet Protocol)
IP (Internet Protocol) communicate across networks, not just physical links. It bridges the gap between different router networks.
There are two versions:
- IPv4 (IP Version 4)
- IPv6 (IP Version 6)
- IP networks can be divided into smaller sections called subnets.
- Subnets are defined using an IP address and an accompanying netmask.
- Netmasks determine the network size and routing rules.
Examples of reserved IP networks include:
- 10.0.0.0/8: Over 16 million IP addresses.
- 172.16.0.0/12: About 1 million IP addresses.
- 192.168.0.0/16: 65,534 IP addresses.
Broadcast Addresses and Localhost
Each network segment has a broadcast address for sending data to all hosts within the network.
Broadcasting means reaching everyone simultaneously.
The smallest netmask is 255.255.255.255 (a single IP address).
To communicate within the same host, we use the local host address: 127.0.0.1.
- For example, in the network 192.168.0.0/24, the broadcast address is 192.168.0.255.
Routers and Packet Routing
Routers are networking devices that forward data between networks. They understand IP formats and route packets accordingly.
The IPv4 Header contains essential details for routing.