The Internet: The Network of Networks Explained

The Internet, often referred to as the network of networks, is a vast system that connects millions of smaller computer networks worldwide. This article explores the structure and nature of the Internet, highlighting its role as a network of networks, and explaining how the Border Gateway Protocol (BGP) plays a crucial part in its functioning.

Understanding the Internet as a Network of Networks

To truly appreciate the Internet's magnitude, it helps to understand its foundational definition. The Internet is not a single network but rather a collection of interconnected networks that communicate using a common set of protocols and standards. Each smaller network, such as Local Area Networks (LANs), Metropolitan Area Networks (MANs), and Wide Area Networks (WANs), contributes to the grand scale of the Internet.

Wide Area Networks (WANs)

Wide Area Networks (WANs) are networks that span large geographic areas, connecting distant devices over long distances. They use high-speed devices and infrastructure like routers, switches, and backbone lines to facilitate communication across vast distances. For instance, Internet itself is a prime example of a WAN, as it connects personal area networks (PANs), LANs, and MANs through these high-speed devices.

The Role of Border Gateway Protocol (BGP)

Among the protocols that maintain the Internet's functionality, Border Gateway Protocol (BGP) is particularly significant. BGP is the de facto standard for carrying routing information between autonomous systems. Each autonomous system (AS) on the Internet acts as a network of routers with a single unique AS number. These AS networks are interconnected, forming a network of networks.

External BGP and OSPF Networks

While External BGP and other Interior Gateway Protocols (IGPs) like Open Shortest Path First (OSPF) are important, they serve slightly different roles. External BGP is used to exchange routing information between different ASes, making it a critical component for the Internet's structure. In contrast, OSPF networks, which are part of a backbone, operate within a single AS.

Types and Topologies of Networks

A network topology describes the physical or logical arrangement of network nodes (like computers and servers) and the links between them. This topology can range from simple point-to-point connections to complex, hierarchical structures.

For example, a home network typically uses a star topology, where all devices are connected to a central hub or modem. In the Internet, the topology is far more complex, with various types of networks and topologies interwoven to form a vast and intricate infrastructure.

The First Computer Network: ARPANET

The story of the Internet begins with ARPANET, one of the first computer networks to use packet switching. Developed in the mid-1960s, ARPANET is considered the direct predecessor of the modern Internet. On October 29, 1969, the first message was sent on ARPANET, marking a pivotal moment in the development of the Internet.

Conclusion

In summary, the Internet is a vast network of interconnected networks, each contributing to the global communication infrastructure. The Border Gateway Protocol (BGP) plays a crucial role in maintaining the functionality of the Internet by facilitating communication between different autonomous systems. Understanding the structure and protocol of the Internet is key to leveraging its power in today's digital world.