Como funciona a Internet? Parte 2: Sistemas Autônomos, BGP, PTTs.

Summary

This video explains how the internet works by breaking it down into key concepts. It highlights the importance of collaboration between independent networks, known as Autonomous Systems (ASes), that form the backbone of the internet. It discusses how these networks use protocols like BGP to share routing information, enabling data to travel across the global network. The video also touches on the role of Points of Traffic Exchange (PTTs) and how networks negotiate commercial or collaborative agreements. Ultimately, it helps viewers understand how the infrastructure of the internet operates behind the scenes to support everyday services.

Takeaways

• 😀 A single attacker, no matter how skilled, cannot win a football match alone—collaboration is essential in daily life, including on the Internet.
• 😀 The Internet is made up of thousands of independent networks, each known as an Autonomous System (AS), which interconnect to form the global network.
• 😀 The Internet relies on a logical layer that separates it from telecommunications, using the IP protocol to assign unique numeric addresses to devices.
• 😀 Services like Google, Facebook, and Netflix are hosted in independent networks, called Autonomous Systems, and are interconnected to enable global access.
• 😀 The backbone of the Internet is made up of large transit providers that link networks globally, forming the core of the network infrastructure.
• 😀 The Internet’s core is neutral and simple—it only transfers data packets, without examining their contents, which allows for scalability and innovation.
• 😀 The BGP (Border Gateway Protocol) is used by ASes to exchange routing information, helping to build maps of the best paths for data packets.
• 😀 In 2014, nearly 50,000 Autonomous Systems were interconnected, with almost 500,000 routes leading to billions of devices worldwide.
• 😀 Many ASes interconnect through Traffic Exchange Points (PTTs), where multiple networks physically connect, enabling efficient data exchange.
• 😀 The relationships between ASes can be commercial (transit) or collaborative (peering), allowing for flexible and independent network interactions across the Internet.

Q & A

What is the main analogy used in the script to explain the importance of collaboration in the Internet?

The script uses the analogy of a football player. It explains that just like a single attacker cannot win a football game alone, collaboration is crucial for the functioning of the Internet. Various systems, services, and networks must collaborate for the Internet to work.

How does the script describe the role of ISPs (Internet Service Providers) in the context of the Internet?

ISPs, like the one Patricia uses, are described as part of a larger network of independent companies that form the Internet. They connect users to the Internet, and each ISP might rely on other providers to form a broader network.

What is a System Autônomo (AS) in the context of the Internet?

A System Autônomo (AS) is an independent network on the Internet, managed and controlled by different companies. These networks collaborate with each other to form the global Internet but have autonomy in their internal operations.

What does the ASN (Autonomous System Number) represent?

The ASN is a unique number that identifies each System Autônomo (AS) on the Internet. This number is used to differentiate and manage these independent networks that make up the global Internet.

What are the different types of Systems Autônomos (AS) mentioned in the script?

The script mentions three types of ASes: service providers or content providers (like Google, Facebook, etc.), access providers (which connect users to the Internet), and transit providers (who offer backbone infrastructure to other ASes).

What role do transit providers play in the Internet?

Transit providers offer large-scale backbone infrastructure that connects different networks across the Internet. They provide 'wholesale' services, much like suppliers in a traditional commerce model, helping other ISPs to route traffic across the network.

What is the 'backbone' of the Internet, and how is it formed?

The backbone of the Internet is formed by large, high-capacity networks operated by transit providers. These networks are present in multiple countries and serve as the central core of the Internet, routing data between different parts of the network.

How does BGP (Border Gateway Protocol) function in the Internet?

BGP is a routing protocol that allows different Systems Autônomos to exchange information about the best routes for data to travel across the Internet. It helps build and maintain a routing table, enabling efficient data transfer between networks.

What is the role of Points of Presence (PTTs) in Internet connectivity?

PTTs are physical locations where multiple networks interconnect. They allow different networks to connect with each other directly, reducing costs and improving efficiency. Networks use PTTs to exchange traffic with many other networks at once.

How does the Internet manage the interconnection between different networks without a central authority?

The Internet operates without a central authority by allowing each network to negotiate its own interconnection agreements. Networks collaborate using common standards and protocols, but they are free to choose their commercial or non-commercial relationships with other networks.