Apr 11, 2025
What is a Load Balancer ?
What is Load Balancing ?
Load balancing is the method of distributing network traffic equally across a pool of resources that support an application. Modern applications must process millions of users simultaneously and return the correct text, videos, images and other data to each user in a fast and reliable manner.
A Load Balancer is a device that sits between the user and the server group and acts as an invisible facilitator, ensuring that all resource servers are used equally.
Benefits of Load Balancing
1. Application Availability
Increases fault tolerance by redirecting traffic from failed servers to healthy ones
Enables server maintenance without downtime
Supports disaster recovery and regular health checks
2. Application Scalability
Distributes traffic efficiently across multiple servers
Prevents bottlenecks and adapts to varying traffic loads
Adds system redundancy to support growth
3. Application Security
Protects against DDoS attacks by spreading traffic
Filters malicious traffic and integrates with firewalls
Enhances overall application defense mechanisms
4. Application Performance
Balances server loads to improve speed and reliability
Reduces latency by routing requests to the nearest server
Optimizes the use of computing resources
How does Load Balancing work ?
Load balancing works by analyzing incoming requests and routing them based on specific policies or algorithms. Traffic is then distributed according to different criteria:
Round Robin: requests are sent sequentially to each server in turn.
Least Connections: Requests are directed to the server with the fewest active connections.
Hash IP: Requests are routed according to the client's IP address to ensure session persistence.
Weighted Round Robin: Servers with higher capacity receive more requests.
For more advanced configurations, load balancers can also perform health checks on the servers. These checks ensure that they are responsive and healthy before directing traffic to them, adding a layer of reliability.
Load balancer definition
A load balancer is a physical or virtual device that distributes network traffic and workloads across multiple servers. This can be a hardware device, software application, or cloud service, with each being adapted to different environments and requirements.
Load balancer types
There are several types of load balancers, each of which meet different needs:
Hardware load balancers: Physical devices used in high-performance datacentres.
Load Balancers software: software solutions installed on servers or containers, offering greater flexibility.
Cloud Load Balancers: Cloud solutions provided by cloud solution providers , offering scalability, ease of use, and reduced overheads for cloud load balancing.