# Content Domain 4: Design Cost-Optimized Architectures
**Topics**
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## Task 4.1: Design cost-optimized storage solutions
](#solutions-architect-associate-03-domain4-task1)
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## Task 4.2: Design cost-optimized compute solutions
](#solutions-architect-associate-03-domain4-task2)
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## Task 4.3: Design cost-optimized database solutions
](#solutions-architect-associate-03-domain4-task3)
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## Task 4.4: Design cost-optimized network architectures
](#solutions-architect-associate-03-domain4-task4)
## Task 4.1: Design cost-optimized storage solutions
Knowledge of:
+ Access options (for example, an S3 bucket with Requester Pays object storage)
+ AWS cost management service features (for example, cost allocation tags, multi-account billing)
+ AWS cost management tools with appropriate use cases (for example, AWS Cost Explorer, AWS Budgets, AWS Cost and Usage Report)
+ AWS storage services with appropriate use cases (for example, Amazon FSx, Amazon EFS, Amazon S3, Amazon EBS)
+ Backup strategies
+ Block storage options (for example, hard disk drive [HDD] volume types, solid state drive [SSD] volume types)
+ Data lifecycles
+ Hybrid storage options (for example, AWS DataSync, AWS Transfer Family, AWS Storage Gateway)
+ Storage access patterns
+ Storage tiering (for example, cold tiering for object storage)
+ Storage types with associated characteristics (for example, object, file, block)
Skills in:
+ Designing appropriate storage strategies (for example, batch uploads to Amazon S3 compared with individual uploads)
+ Determining the correct storage size for a workload
+ Determining the lowest cost method of transferring data for a workload to AWS storage
+ Determining when storage auto scaling is required
+ Managing S3 object lifecycles
+ Selecting the appropriate backup and/or archival solution
+ Selecting the appropriate service for data migration to storage services
+ Selecting the appropriate storage tier
+ Selecting the correct data lifecycle for storage
+ Selecting the most cost-effective storage service for a workload
## Task 4.2: Design cost-optimized compute solutions
Knowledge of:
+ AWS cost management service features (for example, cost allocation tags, multi-account billing)
+ AWS cost management tools with appropriate use cases (for example, AWS Cost Explorer, AWS Budgets, AWS Cost and Usage Report)
+ AWS global infrastructure (for example, Availability Zones, AWS Regions)
+ AWS purchasing options (for example, Spot Instances, Reserved Instances, Savings Plans)
+ Distributed compute strategies (for example, edge processing)
+ Hybrid compute options (for example, AWS Outposts)
+ Instance types, families, and sizes (for example, memory optimized, compute optimized, virtualization)
+ Optimization of compute utilization (for example, containers, serverless computing, microservices)
+ Scaling strategies (for example, auto scaling, hibernation)
Skills in:
+ Determining an appropriate load balancing strategy (for example, Application Load Balancer [Layer 7] compared with Network Load Balancer [Layer 4] compared with Gateway Load Balancer)
+ Determining appropriate scaling methods and strategies for elastic workloads (for example, horizontal compared with vertical, EC2 hibernation)
+ Determining cost-effective AWS compute services with appropriate use cases (for example, AWS Lambda, Amazon EC2, AWS Fargate)
+ Determining the required availability for different classes of workloads (for example, production workloads, non-production workloads)
+ Selecting the appropriate instance family for a workload
+ Selecting the appropriate instance size for a workload
## Task 4.3: Design cost-optimized database solutions
Knowledge of:
+ AWS cost management service features (for example, cost allocation tags, multi-account billing)
+ AWS cost management tools with appropriate use cases (for example, AWS Cost Explorer, AWS Budgets, AWS Cost and Usage Report)
+ Caching strategies
+ Data retention policies
+ Database capacity planning (for example, capacity units)
+ Database connections and proxies
+ Database engines with appropriate use cases (for example, heterogeneous migrations, homogeneous migrations)
+ Database replication (for example, read replicas)
+ Database types and services (for example, relational compared with non-relational, Amazon Aurora, Amazon DynamoDB)
Skills in:
+ Designing appropriate backup and retention policies (for example, snapshot frequency)
+ Determining an appropriate database engine (for example, MySQL compared with PostgreSQL)
+ Determining cost-effective AWS database services with appropriate use cases (for example, DynamoDB compared with Amazon RDS, serverless)
+ Determining cost-effective AWS database types (for example, time series format, columnar format)
+ Migrating database schemas and data to different locations and/or different database engines
## Task 4.4: Design cost-optimized network architectures
Knowledge of:
+ AWS cost management service features (for example, cost allocation tags, multi-account billing)
+ AWS cost management tools with appropriate use cases (for example, AWS Cost Explorer, AWS Budgets, AWS Cost and Usage Report)
+ Load balancing concepts (for example, Application Load Balancer)
+ NAT gateways (for example, NAT instance costs compared with NAT gateway costs)
+ Network connectivity (for example, private lines, dedicated lines, VPNs)
+ Network routing, topology, and peering (for example, AWS Transit Gateway, VPC peering)
+ Network services with appropriate use cases (for example, DNS)
Skills in:
+ Configuring appropriate NAT gateway types for a network (for example, a single shared NAT gateway compared with NAT gateways for each Availability Zone)
+ Configuring appropriate network connections (for example, AWS Direct Connect compared with VPN compared with internet)
+ Configuring appropriate network routes to minimize network transfer costs (for example, Region to Region, Availability Zone to Availability Zone, private to public, AWS Global Accelerator, VPC endpoints)
+ Determining strategic needs for content delivery networks (CDNs) and edge caching
+ Reviewing existing workloads for network optimizations
+ Selecting an appropriate throttling strategy
+ Selecting the appropriate bandwidth allocation for a network device (for example, a single VPN compared with multiple VPNs, Direct Connect speed)