Understanding Delays in Computer Network

Does the data sending and reciving occures at the same instance? What causes the delay?

Way back before, when the concept of 4G was less popular and was not introduced to every corner of the world, people still used to have a craze about social media and online communication platforms. Do you ever observed anyone doing chat during those times? Person A sending a message…..waitng for a second to get his message reached…..Person B receiving the message and giving reply….again waiting for some time to get it received at the other end. A tremendous delay we used to observe at that time. Where does the delay come from? Does it caused due to less bandwidth? What if the bandwidth is far far greater than the actual data size? Does it still gives the delay?

To answer all the questions of this kind, one must have an idea of trasmission of the data packets when data is sent over a network. Let’s consider a well known example of sending a whatsapp message to a friend. The process proceeds in the following way-

1. Message is made (may be in any format audio,video etc.) and send button is clicked. ▶
2. The operating system converts that data into machine understandable form, breaks it and converts it into data packets. And those data packet are put on the link. and that is indicated by a single tick ✔ .The time taken in this process is termed as Transmission Delay.
3. The data packets sent are processed by intermediate routers which processes the header of the packet and chooses the path to which the packet has to be sent. The time taken by the intermediate sites adds Processing delay to the communication.

1. Now, the time taken by the data packet to reach to receivers end from senders end is called as Propagation Delay. Distance and speed of propagation are some of the factors which affects this delay. In case of packet switching when the data is divided into chunks and transmitted, The receiver has to wait for all the data packets to reach, this delay is often termed as Queuing Delay. Once all the packets gets reached, they are arranged and merged in the sequenced format. The data is later fed to the receiver for execution.
2. And finally, When message is reached at the receivers destination and is indicated by double tick ✔✔.

Not only whatsapp, but Delays are observed everywhere in the data communication. However with the increase in bandwidth and strength of the signals etc. factors it can be redused and minimised in the order of miliseconds and microseconds but it is still there. Hope you understood.

Thank You!!