A company is enhancing its online ordering application, which has recently seen an increase in attacks from malicious actors. The updated application will be hosted on an Amazon Elastic Container Service (Amazon ECS) cluster, with Amazon DynamoDB used for data storage. A public Application Load Balancer (ALB) will grant end users access to the application. To prevent attacks and ensure business continuity with minimal service interruptions during ongoing attacks, which two steps will be the most cost-effective solutions?