Securely Accessing SAP CPI Integration from External Systems

Executive Summary

As enterprises accelerate digital transformation, Integration has become a strategic capability rather than a back-office function. Organizations increasingly rely on APIs and cloud-native integration to enable collaboration across partners, customers, and ecosystems. However, securely exposing Integration endpoints—especially within mission-critical SAP environments—remains a complex architectural challenge.

This white paper examines the risks and constraints associated with directly exposing SAP Cloud Integration (CPI) Integration to external systems. It analyzes the architectural limitations, security implications, and compliance considerations, and presents a robust, SAP-recommended solution using SAP Integration Suite and the Process Integration Runtime within SAP Business Technology Platform (BTP).

Designed for IT architects, SAP developers, integration specialists, and business leaders, this paper provides an authoritative, research-backed framework for building secure, scalable, and compliant external integrations.

1. Introduction

In today’s interconnected digital ecosystem, seamless system integration is essential for operational efficiency, real-time decision-making, and business agility. Enterprises are integrating ERP systems, cloud applications, partner portals, mobile platforms, and IoT devices in increasingly complex landscapes.

SAP Integration Suite, which includes SAP Cloud Integration (CPI), provides a comprehensive integration platform-as-a-service (iPaaS) to design, deploy, and manage integration flows (iFlows). However, exposing CPI Integrations to external systems introduces significant security and governance challenges.

SAP explicitly does not support direct internet exposure of CPI runtime endpoints. Attempting to bypass architectural safeguards may result in:

• Unauthorized system access
• Data breaches
• Regulatory non-compliance
• Increased operational risk

This white paper explains why direct exposure is discouraged and presents a secure, scalable architecture leveraging SAP BTP’s Process Integration Runtime as a controlled access layer.

2. Problem Statement: The Risks of Direct CPI Exposure

3. Solution: Secure Access to CPI

3.1 SAP BTP Process Integration Runtime

SAP addresses these challenges through a proxy-based access model within SAP Business Technology Platform. Instead of exposing CPI directly, external systems authenticate against the Process Integration Runtime, which securely proxies validated requests to CPI.

This model enforces:

• OAuth 2.0 token validation
• HTTPS-only communication
• Centralized identity management
• Controlled runtime routing

Process Integration Runtime service enables:

• Secure runtime URL generation
• OAuth 2.0 client credential support
• Service key management
• Controlled access per iFlow

Instances are created under the "integration-flow" plan in BTP subaccounts.

3.2 Security Benefits and Strategic Advantages

Defense-in-Depth

• No direct internet exposure
• Centralized authentication
• Encrypted HTTPS traffic
• Token-based access control

Governance & Auditability

• Access logs captured at runtime
• Traceability for compliance
• Simplified audits

Operational Efficiency

• Faster partner onboarding
• Security changes independent of iFlow redeployment
• Reduced custom gateway development

Scalability

• Cloud-native auto-scaling
• Multi-client support
• Granular entitlement management

4. Real-World Applications

• Manufacturing:
  Suppliers securely submit purchase orders via OAuth-authenticated HTTP calls.
• Retail:
  E-commerce systems sync inventory in real time without exposing internal ERP endpoints.