Unlocking AWS Savings: 10x Advanced Network Cost Optimization in AWS techniques
In my latest blog post, I dive into effective strategies for optimizing AWS network costs,
Published Nov 9, 2024
Introduction
As organizations accelerate their journey to the cloud, cost optimization quickly becomes a critical focus, especially as cloud spend can fluctuate widely monthly. This variability often leads to increased organizational scrutiny and drives the need for proactive cost management to keep cloud expenditures in check. With a suite of native tools from hyperscale cloud providers and a range of third-party solutions, the options for cost optimization are robust and varied. Some System Integrator Organizations (Sis) even offer cost optimization as a managed service, guiding end customers through complex savings strategies.
Cost optimization is a top priority, and while hyper-scalers offer various strategies for optimizing cloud services, much of the effort tends to focus on computing and database resources, which are usually the major contributors to monthly spend. However, in modern application architecture built on services like EKS, Lambda, API Gateway, S3, and SQS, network costs become a significant factor. Unlike other areas, there are fewer built-in strategies for optimizing network expenses in the cloud.
This blog will explore effective strategies specifically for reducing network costs in AWS Cloud.
Refer to my previous post on Cloud Financial Management and Cost avoidance strategies:- https://www.linkedin.com/feed/update/urn:li:activity:6915574816464928768/
1. Centralized Network Design
In this approach, a central network account (often called a "Hub") hosts all core network components. This setup manages connectivity among VPCs, data centers over VPN or Direct Connect, and security systems like firewalls and intrusion detection. By routing traffic to the internet and data centers through a single exit point, it reduces the need for multiple Direct Connect links, VPNs, and security devices. This consolidation streamlines resources and cuts costs by avoiding redundant network stacks
2. AWS NAT Gateway vs. NAT Instance vs. Third-Party Solutions
AWS offers NAT services to enable outbound internet access from private subnets, replacing private IPs with a public IP on the NAT system for secure communication. NAT Gateways simplify management by avoiding the need for individual public IPs. However, AWS charges NAT services based on data transfer, with costs for internet egress and ingress.
For larger private subnets or repetitive usage patterns (e.g., frequent access to the same URLs), third-party NAT solutions may be more cost-effective. These solutions often include features like DNS firewalls, caching, and URL filtering, which can reduce the need for additional security tools and offer enhanced functionality.
3. Interface and VPC endpoint
Most AWS services—such as KMS, Lambda, S3, DynamoDB, and CloudWatch—are configured with public endpoints by default. When workloads in private subnets access these services, traffic flows through a NAT Gateway, incurring network egress (internet outbound) charges. This setup adds costs as traffic from private subnets must traverse the NAT Gateway to reach public interfaces of these services. The data flow is as shows in the below diagram.
VPC Interface endpoint using AWS Private Link
As show in the above diagram, In VPC Interface endpoint setup, AWS deploys a network interface within one of your defined subnets to connect directly to the AWS service. Traffic destined for the service resolves to the private IP of the endpoint's network interface via DNS, enabling a private connection between the VPC and the AWS service. For example, CloudWatch can use an interface endpoint for this connection.
Data transfer via an interface endpoint costs $0.01 per GB for the first 1 PB within the same region, compared to $0.045 per GB when routing through a NAT Gateway, which also incurs a fixed monthly fee of $32.85 per gateway. This cost difference becomes significant at high data volumes, making interface endpoints a more cost-efficient choice.
4. Transit Gateway Sharing
For efficient network traffic control and segmentation, it's optimal for multiple accounts to share a single, central Transit Gateway (TGW). Each TGW incurs an hourly cost of $0.10 (approximately $73 per month) plus additional charges for data processing and cross-region peering. Using a central TGW shared across accounts allows each account to connect its VPCs to the centralized TGW, optimizing both cost and network management, as shown in the diagram below.
5. Cross -Zone load balancing
It allows Load Balancers to distribute traffic across targets in different Availability Zones (AZs). However, this may result in cross-AZ data transfer charges. For non-critical applications, consider disabling cross-zone load balancing to reduce costs. Instead, route traffic to targets within the same AZ using local backend service endpoints to avoid unnecessary data transfer fees.
6. Transit Gateway Vs VPC Peering
Transit Gateway (TGW) is a scalable cloud router that simplifies and centralizes network management. It incurs data processing charges of approximately $0.02 per GB for VPC-to-VPC communication. However, if you need to transfer large volumes of data between VPCs (within the same or across accounts), using VPC peering may be a better choice, as it is free of charge and has no bandwidth limitations.
7. Embrace Direct Connect SiteLink
Direct Connect SiteLink enables seamless data transfer between Direct Connect locations, bypassing AWS Regions. This feature allows you to create reliable, global connections between your offices and data centers by routing data over the fastest path between AWS Direct Connect locations, enhancing performance and reducing latency across your global network
As shown in the diagram above, customer data centers DC1 and DC2 can communicate directly with each other via AWS Direct Connect. These links enable seamless communication between the data centers, AWS workloads, and even between other data centers, ensuring a reliable and efficient network connection across the entire infrastructure.
8.Resiliency leveraging Direct Connect and VPN combination.
It’s ideal to have multiple dedicated Direct Connect connections for a hybrid network to ensure resiliency, but this comes at a cost. As a cost-efficient alternative, you can leverage AWS VPN as a backup solution for your primary Direct Connect connection.
To achieve redundancy without compromising bandwidth, consider this approach: If you have a 10 Gbps Direct Connect connection with an average bandwidth usage of 5 Gbps (50%), you can create multiple VPNs to meet your bandwidth needs. For instance, setting up 5 VPNs, each with a maximum throughput of 1.25 Gbps, will provide a combined 6.25 Gbps of bandwidth. Using Equal-Cost Multi-Path Routing (ECMP) and BGP, as shown in the diagram below, can ensure efficient traffic distribution and redundancy while meeting your bandwidth requirements
9. Share Network Links Leveraging Direct Connect
In scenarios where workloads are deployed across multiple regions and connectivity from multiple regional data centers (DCs) to AWS is required, the typical solution involves establishing multiple Direct Connect connections from each office to AWS. This results in separate connections from each data center to the nearest AWS region. However, with the introduction of AWS Direct Connect Gateway, a global construct, you can share a single Direct Connect connection to reach workloads in different AWS regions. This approach reduces the need for multiple regional connections and simplifies network management while maintaining secure and efficient connectivity
10. Global Accelerator vs. Route 53-Based Load Balancing
AWS Global Accelerator enhances the performance of multi-regional applications by utilizing Anycast IP addresses, multiple Points of Presence (POPs), and providing higher reliability. It acts as a unified access point for your applications, with endpoints such as Application Load Balancers (ALB), EC2 instances, or containers as show in below diagram. Global Accelerator incurs an additional cost of $0.025 per hour, along with data processing charges.
For certain global applications that do not require the advanced capabilities of Global Accelerator, AWS Route 53’s DNS routing features—such as latency-based, geolocation, geoproximity, and weighted routing—can be a cost-effective alternative. It’s essential to evaluate the specific performance and routing requirements of the application to determine whether Global Accelerator is necessary, or if Route 53’s routing policies will meet the needs effectively.
Summary
In conclusion, optimizing network costs and performance in AWS requires choosing the right tools for your needs. Whether it's using Direct Connect, centralized network designs, or services like Global Accelerator and Route 53, it’s important to consider factors like traffic patterns and scalability. By understanding these options, you can make cost-effective choices that meet both your performance and budget goals for a more efficient AWS network.