Internet Architecture

The internet is the hardware that runs applications like the World Wide Web, which is software. This lesson covers basic internet architecture, packet switching for routing information, TCP/IP protocol for managing traffic, and organization into different abstraction layers.

The Internet is a network of disparate networks connected by routers. Host computers are represented as colored dots and messages travel through routers to reach their destination. Hosts have IP addresses or domain names, while routers transmit data between networks within the internet.

Using Network Tools for Pinging Learn how to use network tools, specifically the ping utility, to reach hosts on the Internet. By entering a domain name and clicking 'Go', you can view information such as IP address, sent packets, round-trip time, and average latency.

Data Traveling Through the Internet Understand packet switching as the protocol used for data transmission over the internet. Messages are broken into small packets (p1 p2 p3) which take different routes through networks before being reassembled at their destination in order.

In the 1950s, concerns about nuclear attacks led to the development of a decentralized network architecture with multiple paths between any two points. This design allowed messages to be divided into small packets and routed independently, providing redundancy that could withstand outages and disasters.

Packet switching is different from circuit switching. Circuit switching uses a dedicated channel that remains constant throughout the call, like landline communication.

In a packet switch network, there is no sustained connection. Each voice packet in a phone call is shipped through the internet along multiple routes, creating the impression of continuous connection.

Traceroute, also known as trace route, allows us to track the path of packets through the Internet. By using network tools like MIT's trace tool, we can observe packets being routed through different routers and computers on the network. The number of hops may vary each time a traceroute is performed. We can use network tools to trace routes to different addresses and explore how geographical location affects latency.