WHAT IS TCP UDP ICMP AND HOW IT WORKS

What is TCP/IP and how it works?

TCP stands for Transmission Control Protocol. If you want what is protocol you can read this tutorial, networking protocols with Nmap. I already said to you that it is the most used protocol on the net and if you want to know why it is used that much heavily continue to read. Another point is TCP is also called an Internet protocol and TCP/IP.

TCP and UDP are the two protocols that are used to transfer data and here we are with TCP. Before TCP is going to transfer data it performs a three-way handshake to confirm some details about the destination

  1. Sync handshake (SYN) contains all the details of important port numbers and initialization sequences about data transfer. When all the port numbers and permissions to that port numbers are going good then it sends acknowledgement details to the source
  2. Sync and Acknowledgement(ACK) shake is after performing above step the acknowledgement is sent to the source with SYN/ACK details then the third handshake takes place
  3. ACK shake is again an acknowledgement from the source that it received all the acknowledgement and sync details and now it is able to send all the data to the source and destination

This happens whenever the TCP connection is going to be established.

Why TCP is mostly used?

TCP performs all the steps mentioned above and this helps TCP to confirm that the device is present and working actively. What if these steps are not performed? If data is sent directly, for example, the data is sent to port 21(ftp) and if that port is closed then all the data sent there will be discarded which leads to data loss. In the place of TCP, this won’t happen. First, it confirms the device and then transfers the data so this most used.

This is what is TCP and working on it. If you like this you can share it if it is possible.

What is UDP and how it works?

UDP stands for User Datagram Protocol is direct connection protocol.

It will have the data and the destination data from the source and then it moves to deliver the data. It won’t confirm that there is a device or not whether the port is open or not if the port is closed when the data sent is discarded or it is delivered.

How it is helpful?

It is helpful while transferring the data of VoIP (Voice Over IP) while calls they use UDP because we won’t have that much time to make sure whether the device is there or not, ports are open or not because the data will be lost so in these type of situations UDP is very helpful.

What is ICMP and how it works?

Finally now in this article, I am going to say you what is ICMP and how it works.

ICMP stands for Internet Control Message Protocol. If you already looked at my last tutorials on UDP and TCP you will understand this protocol very easily. If you didn’t go and have a look at it these are the links

As UDP and TCP ICMP won’t carry any data then how this is useful. ICMP is an informing protocol. For example a packet of data sent to UDP port then the source won’t get any info about the delivery of the packet. In UDP if the port is closed when the data will be ignored and no information is sent to source that data is ignored and here there will be ICMP to inform about the data. The name itself says that it is a message protocol.

This is what is ICMP and its working. If you like this don’t forget to share this.