Load Balancing in AWS

What is Load Balancing

Load Balancing is the process of distributing network or application traffic across multiple servers to improve performance, reliability, and resource utilization. By spreading the load, it ensures no single server becomes overwhelmed, enhancing response times and maintaining high availability. This provides redundancy to minimize downtime to minimize downtime in case of server failures and supports scalability by allowing easy addition or removal of servers as demand fluctuates. Load Balancers can be hardware, software or a combination, using algorithms like round-robin, least connections, or IP hash to allocate traffic efficiently.

Load Balancing is required to optimize the performance, reliability and scalability of network services or applications. It prevents any single server from becoming a bottleneck by distributing traffic across multiple servers, thereby ensuring faster response times and better utilization. This distribution also provides redundancy, so if one server fails, others can take over, minimizing downtime and ensuring continuous availability.

AWS Load Balancing

AWS load balancing is a service from AWS that distributes In coming traffic cross multiple targets such as Amazon EC2 instances, containers, and IP addresses , to ensure high availability and reliability.

Target Groups

Target Groups in AWS are collections of targets that receive traffic from AWS load balancers. They facilitate efficient load distribution allowing load balancers to route requests across multiple targets based on configured rules. Target groups include features such as health checks to monitor target status and automatically remove unhealthy targets, flexible routing options based on criteria like path patterns and HTTP headers, and seamless integrations with AWS services for automated scaling and deployment management. They are essential for optimizing application availability and ensuring scalable and reliable traffic handling with AWS environments.

Types of load balancers in AWS

Application Load Balancer(ALB):

ALB distributes incoming application traffic across multiple targets. It operates at application layer, it routes requests based on content such as URLs and HTTP headers, making it perfect for micro services and container applications. With Automatically scaling, ALB ensures high availability and fault tolerance, offering a flexible and scalable solution for web applications on AWS.

In AWS ALB, rules specify how incoming traffic is directed to different target groups based on conditions like path patterns, host headers, HTTP methods, and query strings. These rules enable precise traffic routing with a single ALB instance, allowing dynamic adjustments through the AWS management console,CLI or API. This flexibility is crucial for efficiently managing traffic in micro services architectures and adapting to evolving application needs and traffic patterns.

ALB supports:

1. WebSocket and HTTP/2

2. Provides SSL/TLS security

3. Integrates with AWS CloudWatch and CloudTrail for monitoring and logging

4. Supports user authentication via AWS Cognito or OpenID Connect.

Network Load Balancer(NLB):

The NLB in AWS is a highly scalable and performant load balancing solution that operates at the transport layer(Layer 4) of the OSI model. It efficiently distributes incoming TCP and UDP traffic across multiple targets. NLB supports static IP addresses for clients, reserves the source IP of incoming requests(ideal for applications that require client IP preservation), and provides high throughput and low latency. It integrates seamlessly with other AWS services, supports health checks for automatic target registration and deregistration, and offers configurable cross-zone load balancing to ensure even distribution of traffic across all available targets.

Gateway Load Balancer(GWLB):

The Gateway Load Balancer in AWS streamlines the deployment and scaling of network virtual appliances, such as firewalls and intrusion detection systems. It functions as a managed service that distributes traffic across multiple instances of these appliances, ensuring scalability and high availability for inbound and outbound traffic without necessitating alterations to your current network setup.GWLB seamlessly integrates with AWS services, providing automated scaling, health checks for resilience, and centralized management via AWS console or APIs. This makes it well-suited for improving the security, dependability , and efficiency of network infrastructure on AWS.

Another type of load balancer is Classic Load Balancer, which is currently deprecated.

To summarize, Load Balancers play a vital role in the world of networking.They are the devices that actually takes the requests to the application from the end user.