Types of Elastic Load Balancing (ELB)

When I was preparing for my AWS Solutions Architect - Associate (SAA-C03) exam, I found so many good topic that I want to share. One of them is Types of ELB.

So here are few question that click in my mind:
What is ELB ??
Are there 3 or 4 types of ELB ??.
Do we use all types, when and where ??

So here are my finding on this topic.

ELB - Elastic Load Balancing. ELB automatically distributes incoming applications traffic across multiple targets such as Amazon EC2 instances. This can be done across multiple AZs.

Types: 3 or 4 ??

There are 4 types of ELB.

Application Load Balancer - ALB
Network Load Balancer - NLB
Gateway Load Balancer - GWLB
Classic Load Balancer - CLB
Are we using all ???

No CLB is a Legacy and so it is deprecated. But AWS encourages users to migrate to ALB or NLB - Why ?? See Details of each LB.

Application Load Balancer - ALB :

1. Routing HTTP/HTTPS traffic
2. Support Websocket
3. ALB Operate on Layer 7 of OSI Model. 7th Layer is Application Layer of OSI Model.
4. Intelligent Load Balancers

Network Load Balancer - NLB :

1. Routing TCP,TLS,UDP,TCP_UDP traffic
2. NLB operates on Layer 4 of OSI Model. 4th Layer of OSI model is Transport Layer.
3. It can handle millions of request per second. So when a user need to route thousands or ten thousands of concurrent connections they need NLB.
4. Performance Load Balancer

Classic Load Balancer - CLB :

1. Legacy load balancer.
2. Load Balance for HTTP/HTTPS traffic.
3. Use Layer 7 OSI Model specific features such as X-Forwarded & sticky sessions .

Gateway Load Balancer - GWLB :

1. Routing IP traffic
2. GWLB operates on Layer 3 of OSI Model. 3th Layer of OSI model is Network Layer.
3. GWLB used to deploy, scale and run third-party virtual appliances like custom firewalls. More details on third-party appliances can be found here:
   

   Third-party Virtual Appliances

   KomalLM ・ Feb 12

   #aws #elb #gatewayloadbalancer #beginners

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