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🌐 What Happens When You Hit a URL in the Browser?

📝 Steps​

  1. DNS Resolution
  2. TCP Three-Way Handshake
    1. The client creates a connection to the server to transfer and receive data. TCP is one of the underlying protocols in Hypertext Transfer Protocol (HTTP).
    2. The client performs a three-way handshake with the server to establish a TCP connection. TCP requires a three-way handshake because of the bi-directional communication channel. If you make a two-way handshake, you can only start a single-directional communication channel.

    1. The following synchronize (SYN) and acknowledge (ACK) messages are sent between the client and the server to open a TCP connection:
      1. The client sends a SYN request with a random sequence number (x).
      2. The server responds with SYN-ACK. The acknowledgment number is set to one more than the received sequence number (x+1). The server sends another random sequence number (y).
      3. The client sends ACK. The client sends an acknowledgment number that is one more than the received sequence number (y+1).