Solution Design Document for Prescription Payment Program (PPP)

1. Project Overview

The Prescription Payment Program (PPP) is a CMS-mandated initiative aimed at providing real-time prescription cost-sharing information to beneficiaries. This project implements the solution for a health plan to comply with federal requirements while ensuring secure, efficient, and scalable operations.

2. Solution Architecture

The solution follows a microservices-based architecture using AWS services for compute, storage, and API management. Key components include:

• API Gateway: Manages external API requests securely.
• Lambda: Executes business logic for prescription processing.
• DynamoDB: Stores prescription cost-sharing information.
• S3 Bucket: Stores prescription-related documents.
• SNS: Sends notifications for processing outcomes.
• CloudWatch: Monitors system performance and logs errors.

3. High-Level Design

3.1 Data Flow

1. User Request: Beneficiary or pharmacy submits a request for cost-sharing details via the API Gateway.
2. Lambda Processing: API Gateway triggers a Lambda function to process the request.
3. Data Retrieval: Lambda retrieves prescription details from DynamoDB.
4. Response: Lambda returns cost-sharing details to the requester.
5. Notification: SNS sends alerts for failed or completed transactions.

3.2 API Endpoints

• POST /prescription/cost - Calculate prescription cost.
• GET /prescription/{id} - Retrieve prescription details.
• PUT /prescription/{id} - Update prescription record.

3.3 Database Design

• DynamoDB Table: PrescriptionPaymentTable
  • PrescriptionID (Primary Key)
  • BeneficiaryID
  • DrugCode
  • CostSharingAmount
  • Status

4. Infrastructure Design

AWS Resources

• S3: prescription-payment-program-data
• DynamoDB: PrescriptionPaymentTable
• Lambda: PrescriptionPaymentHandler
• API Gateway: PrescriptionPaymentAPI
• SNS: prescription-payment-notifications
• CloudWatch: /aws/lambda/PrescriptionPaymentHandler

Infrastructure as Code (IaC)

Terraform templates manage the provisioning of AWS resources. The main.tf file defines resources, while variables.tf and outputs.tf streamline deployment.

5. Security and Compliance

• Authentication: OAuth2.0 with JWT tokens.
• Encryption: AWS-managed encryption for S3 and DynamoDB.
• IAM Roles: Fine-grained access controls for Lambda and API Gateway.
• HIPAA Compliance: Data-at-rest and in-transit encryption.

6. Monitoring and Logging

• CloudWatch Logs: Monitors Lambda execution.
• CloudWatch Alarms: Alerts for failed API requests.
• X-Ray: Traces API request flows for debugging.

7. Deployment and CI/CD

• Pipeline: GitHub Actions for automated build, test, and deployment.
• Stages:
  • Build: Validate code and dependencies.
  • Test: Run unit and integration tests.
  • Deploy: Provision AWS infrastructure and deploy Lambda functions.

8. Error Handling and Notifications

• Retry Mechanism: SQS queues for failed requests.
• SNS Alerts: Notification for failed transactions and system outages.

9. Success Metrics

• Performance: API response time under 500 ms.
• Scalability: Supports 1,000+ concurrent requests.
• Error Rate: Less than 1% of requests fail.

10. Conclusion

This solution ensures CMS compliance, enhances beneficiary experience, and provides a scalable and secure architecture for prescription cost-sharing operations.

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This document is for demonstration purposes and does not contain any sensitive or proprietary information.