Networking II - Ports, Layers, Client-Server Architecture, Web Servers
Learning Goals
After this lab you will be able to
- Recognise the importance of ports in networking
- Understand how computer networking is organized into protocol layers
- Get familiar with the popular client-server architecture for network-based services and see it in action in the context of a web server
Layers and Ports
Protocol Layers
To better understand how computer networking is organized you should read section 1.5.1 from page 77 to page 82 of the book. Again, if you read the entire first chapter, this is already covered.
Optionally, you can also read section 1.5.2 to get a better overview of how information is handled through different layers (encapsulated).
Ports
We saw that IP address are useful for identifying a machine/server's location, or address. We also mentioned that in each address we can have several services or applications, with their respective ports or doors to reach them. To learn more about this, you should read sections 2.1.1 and 2.1.2, on pages 114 to 118.
Client-Server Architecture
In our next lab, you will use one container as a client and the other as a server. To better understand what a server is, watch the following videos.
This first video explains the most basic concept (relevant segment: 09:36-11:36).
This one goes into significantly more detail. You only need to watch the first 3 min. but the rest of the video is also interesting and provides generally useful information.
Docker
You already worked with Virtual Machines, which can virtualize the hardware of an entire computer and run different operating systems. Additionally, you have already seen Docker containers in action when you created hosts in the GNS3 environment. Docker offers an alternative to fully virtualizing an entire machine by utilizing containerization. Check the video below for an introduction on Docker's approach.
To read more about the difference between VMs and containers, you can read this blog post.