Understanding the communication between the server and browser

Inbanithi R — Mon, 22 Jun 2026 04:45:13 +0000

Hello everyone this post is all about what I learned for few days about the system design and web technologies.

Isolation:

To get to know about the isolation we need to understand about transactions. Transaction is a multiple query runs as single operation.
If one of the queries fails, then all the queries in that transaction are canceled (Rollback).

Isolation allows multiple transaction to work simultaneously without interfering with changes made by one transaction.
There are various Isolation levels some includes:

Repeatable Read
Serializable

Short Polling:

It is a technique were frontend send a request to the backend over fixed time to get the new changes in the data.
Disadvantage:

Many unnecessary http requests are sent to the server

Long Polling:

It is a technique were frontend sends a request to the backend and server holds the request and sends back a response when new data arrived.
The request may be closed after timeout.

Server Sent Events (SSE):

SSE allows browser to connect to the server, and server will be able to send the data to browser continuously.
It is one way communication (Server to Browser).

Web Socket:

It creates a channel between the server and frontend, unlike SSE it allows two-way communication.
Both server and frontend can send messages continuously.