AWS Elastic Load Balancing (ELB) vs Google Traffic Director: What are the differences?

Key Differences between AWS Elastic Load Balancing (ELB) and Google Traffic Director

Amazon Web Services (AWS) Elastic Load Balancing (ELB) and Google Traffic Director are both load balancing solutions that help distribute network traffic across multiple servers or instances. However, there are several key differences between these two services.

1. Infrastructure: One major difference between AWS ELB and Google Traffic Director is their underlying infrastructure. AWS ELB is a fully managed service provided by Amazon, which means that AWS takes care of all the hardware and software required to run the load balancer. On the other hand, Google Traffic Director is a software-defined networking (SDN) solution that operates at the edge of Google's network.

2. Load Balancing Algorithms: While both AWS ELB and Google Traffic Director support various load balancing algorithms, they have different default algorithms. AWS ELB uses a round-robin algorithm by default, meaning that each incoming request is distributed sequentially to the available servers in a circular order. Google Traffic Director, on the other hand, uses a least request algorithm by default, which directs each request to the server with the fewest active requests.

3. Service Discovery: Another notable difference is the approach to service discovery. AWS ELB supports both DNS-based and API-based service discovery. It offers features such as Amazon Route 53 DNS and AWS Cloud Map for managing the service endpoints. In contrast, Google Traffic Director relies on xDS-based service discovery, which uses the Envoy proxy as the sidecar to communicate with the control plane for discovering and routing to services.

4. Integration with other Services: AWS ELB integrates seamlessly with other AWS services, making it easier to deploy and manage applications within the AWS ecosystem. It has native integrations with services like Amazon EC2, Amazon ECS, and AWS Auto Scaling. Google Traffic Director, on the other hand, is tightly integrated with the Google Cloud Platform (GCP), allowing direct integration with services like Google Kubernetes Engine (GKE) and Google Compute Engine (GCE).

5. Protocol Support: AWS ELB supports a wide range of protocols, including HTTP, HTTPS, TCP, and SSL/TLS. It also provides advanced features like SSL/TLS termination and load balancing of WebSockets. In comparison, Google Traffic Director focuses primarily on HTTP and gRPC-based applications, providing more advanced features for those protocols.

6. Pricing and Billing: Pricing models and billing structures differ between AWS ELB and Google Traffic Director. AWS ELB offers various pricing options, including pay-as-you-go and reserved instances, with charges based on factors such as the number of load balancers, data transfer, and SSL certificates. Google Traffic Director, on the other hand, falls under the standard pricing structure of Google Cloud, with charges based on factors like network egress, instance usage, and any additional services used.

In summary, AWS Elastic Load Balancing (ELB) and Google Traffic Director differ in terms of infrastructure, load balancing algorithms, service discovery, integration, protocol support, and pricing. Both options have their own strengths and suitability depending on the specific requirements and ecosystem in which they are being used.