---
title: What is a Load Balancer?
description: Distributes network traffic across multiple servers to optimize resources.
image: 'https://assets.bytebytego.com/diagrams/0261-what-is-a-load-balancer.png'
createdAt: '2024-02-28'
draft: false
categories:
  - api-web-development
tags:
  - Load Balancing
  - Networking
---

![](https://assets.bytebytego.com/diagrams/0261-what-is-a-load-balancer.png)

A load balancer is a device or software application that distributes network or application traffic across multiple servers.

*   **What Does a Load Balancer Do?**

    *   Distributes Traffic
    *   Ensures Availability and Reliability
    *   Improves Performance
    *   Scales Applications

*   **Types of Load Balancers**

    *   Hardware Load Balancers: These are physical devices designed to distribute traffic across servers.
    *   Software Load Balancers: These are applications that can be installed on standard hardware or virtual machines.
    *   Cloud-based Load Balancers: Provided by cloud service providers, these load balancers are integrated into the cloud infrastructure. Examples include AWS Elastic Load Balancer, Google Cloud Load Balancing, and Azure Load Balancer.
    *   Layer 4 Load Balancers (Transport Layer): Operate at the transport layer (OSI Layer 4) and make forwarding decisions based on IP address and TCP/UDP ports.
    *   Layer 7 Load Balancers (Application Layer): Operate at the application layer (OSI Layer 7).
    *   Global Server Load Balancing (GSLB): Distributes traffic across multiple geographical locations to improve redundancy and performance on a global scale.