class12.md

Class 12 Reading: Socket.io

Resources

• Web Sockets
• Socket.io Tutorial
• Socket.io vs Web Sockets
• OSI Model Explained
• TCP Handshakes Explained
• Socket.io Docs
• Socket.io Server API
• Socket.io Client API
• Socket Testing Tool
• Class README

Web Sockets

1. What is a web socket?

   • A web socket is a communication protocol that provides a full-duplex communication channel over a single TCP connection. It is used to create interactive web applications that support real-time communication between a client and a server.

2. Describe the Web Socket request/response handshake and what happens once the connection is established.

   • The client sends a request to the server to establish a connection. The server responds with a 101 status code if the connection is successful. Once the connection is established, the client and server can send messages to each other.

3. Web Sockets provide a standardized way for the server to send content to a client without first receiving a ____ from that client.

   • Web Sockets provide a standardized way for the server to send content to a client without first receiving a request from that client.

Socket.io Tutorial

1. What does the event handler io.on() do?

   • The event handler io.on() listens for events and executes a callback function when the event is triggered.

2. Describe some possible proof of life or proof that the code works as expected:

   • The server console logs a message when a client connects to the server.
   • The client console logs a message when the client connects to the server.
   • The client console logs a message when the client receives a message from the server.
   • The server console logs a message when the server receives a message from the client.

3. What does socket.emit() do?

   • The socket.emit() method sends a message to the server.

Socket.io vs Web Sockets

1. What is the difference between WebSocket and Socket.io?

   • WebSocket is a communication protocol that provides a full-duplex communication channel over a single TCP connection. Socket.io is a library that enables real-time, bidirectional and event-based communication between the browser and the server.

2. When would you use socket.io?

   • Socket.io is used to create interactive web applications that support real-time communication between a client and a server.

3. When would you use WebSockets?

   • WebSockets are used to create interactive web applications that support real-time communication between a client and a server.

OSI Model Explained

1. What are a couple of takeaways from this video?
   • The OSI model is a conceptual model that describes the communication functions of a telecommunication or computing system without regard to its underlying internal structure and technology.
   • The OSI model is a conceptual model that describes the communication functions of a telecommunication or computing system without regard to its underlying internal structure and technology.
   • The OSI model is a conceptual model that describes the communication functions of a telecommunication or computing system without regard to its underlying internal structure and technology.

TCP Handshakes Explained

1. Translate the gist of the video to a non-technical friend.
   • The TCP handshake is a three-way process that establishes a connection between a client and a server. The client sends a SYN packet to the server. The server responds with a SYN-ACK packet. The client responds with an ACK packet. The connection is established.

Bookmark and Review

• Socket.io Docs
• Socket.io Server API
• Socket.io Client API
• Socket Testing Tool

Reflection

• Class README

1. What are your learning goals after reading and reviewing the class README?

   • Goal 1: I want to understand how to use Socket.io to create interactive web applications that support real-time communication between a client and a server.

Things I Want to Know More About

1. Question 1?
   • Answer 1.