Rudra Gupta’s Post

Before an HTTP request is sent from a client to a server,  a TCP connection is established. It is also called a TCP 3-way handshake. The connection is established in the following steps- SYN: The client sends a TCP SYNchronize packet to the server to inform the server about the client's communication. SYN-ACK: The server receives the SYN and sends back a SYNchronize-ACKnowledgement packet confirming what sequence number it should able to start tracking the packets. ACK: The client acknowledges the response from the server and sends an ACK packet. The server receives the ACK packet, thereby establishing the TCP socket connection. Once the connection is established, the data in our POST/GET requests are transmitted over the network. #softwareengineering #softwaredevelopment #networking

Just a friendly reminder!! TCP/IP 3 Way Handshake : Between the client and the server, there is a system for synchronizing and acknowledging any request that is known as a three-way handshake. This handshake is used to establish a TCP connection between two devices. Here, we will take a simplified look at how communications are established to a web server. Depending on the exact protocol, there may be additional connection negotiation taking place. First, the client sends synchronization (SYN) packet to the web server’s port 80 or 443. This is a request to establish a connection. The web server replies to the SYN packet with an acknowledgement known as a SYN/ACK. Finally, the client acknowledges the connection with an acknowledgement (ACK). At this point, the basic connection is established, and the client and host will further negotiate secure communications over that connection

In a nutshell - TCP Handshake Simplified When a client and server talk to each other, they often use TCP (Transmission Control Protocol). TCP connection between client and server starts with a process called TCP Handshake. It occurs in 3 steps, sometimes referred as 3-way handshake. The handshake is for both client and server to confirm that when they send a message through, the opposite party can receive. SYN ( Synchronise ) Client sends a message to the server and requires proof from the server it has received. SYN ACK ( Synchronise Acknowledge) The server receives the message from the client and sends two messages back to the client: 1. Acknowledging it is able to receive the message from client 2. Requesting proof from the client it has received this message from the server ACK (Acknowledge) Client sends back a message to the server acknowledging that it is able to receive the message from the server

The server generates HTTP status codes that indicate the outcome of an HTTP request. Here are the most important ones you should know: 👇

HTTP status codes are used by a server to respond to a client’s request. They are typically returned in the format of 3-digit codes. The first digit represents the class of response, while the second two digits represent the specific response.

HTTP Response Status Codes [1] 1xx Informational - 100 Continue - 101 Switching Protocols - 102 Processing [2] 2xx Successful - 200 OK - 201 Created - 204 No Content [3] 3xx Redirection - 301 Moved Permanently - 302 Found (Moved Temporarily) - 304 Not Modified [4] 4xx Client Errors - 400 Bad Request - 401 Unauthorized: - 403 Forbidden - 404 Not Found [5] 5xx Server Errors - 500 Internal Server Error: - 502 Bad Gateway: - 503 Service Unavailable - 504 Gateway Timeout