📡 Navigating Options for Cloud UC: A Guide for CSPs

🌍 Setting the Stage for PSTN Integration with Cloud UC

As businesses migrate to cloud-based Unified Communications (UC) platforms like Microsoft Teams, Cisco Webex, and Zoom One, the demand for robust PSTN (Public Switched Telephone Network) integration has surged. For Communications Service Providers (CSPs), integrating PSTN services seamlessly presents both a challenge and an opportunity.

The ability to integrate PSTN services effectively is essential for:
✅ Supporting clients through complex transitions
✅ Retaining customer loyalty
✅ Expanding service reach

This guide outlines the primary PSTN integration options available for CSPs, covering infrastructure-based solutions, cloud-based models, mobile integrations, and compliance programs.

🔌 Core PSTN Integration Options for Cloud UC Platforms

1️⃣ Infrastructure-Based Integration: SBC in the CSP Network

A Session Border Controller (SBC) within the CSP’s own network provides a foundational approach to PSTN integration. The SBC acts as a secure interface between the UC platform and PSTN services, enabling flexibility, security, and compliance.

🔹 Key Advantages:
✔ Security & Control – Direct control over voice traffic ensures security and customisation.
✔ Scalability – Ideal for CSPs serving clients with complex telephony needs or regulatory requirements.

2️⃣ Cloud Calling Platform: SBC with Management Environment

For CSPs seeking streamlined management, a Cloud Calling Platform combines SBC capabilities with session management, user provisioning, and multi-tenant support. Hosted in the CSP’s network or a third-party cloud, this solution simplifies administration.

🔹 Key Advantages:
✔ Ease of Management – Built-in tools simplify deployment and maintenance.
✔ Flexibility – Scales efficiently and ensures consistent service across diverse client bases.

3️⃣ Integrated Cloud Calling Solutions: Lines, Minutes, and Management

Some providers offer a fully integrated Cloud Calling Solution, bundling PSTN lines, calling minutes, and management tools. This approach simplifies PSTN integration for CSPs.

🔹 Key Advantages:
✔ Speed to Market – Quick deployment with all components pre-packaged.
✔ Reduced Complexity – No need for separate provisioning or management.

4️⃣ Cloud Calling Marketplace: Lines, Minutes, and Application Delivery

The Cloud Calling Marketplace model provides PSTN services alongside value-added features, such as call recording, analytics, and compliance tools. This is ideal for CSPs delivering comprehensive service packages.

🔹 Key Advantages:
✔ Value-Added Services – Access to bundled apps enhances client value.
✔ Customisation – CSPs can choose between bundled or independent integrations.

📜 Operator Connect, Cloud-Connected PSTN, and Provider Exchange Programs

Each major UC platform offers structured programs for PSTN integration, ensuring seamless connectivity and compliance.

🔹 Microsoft Teams: Operator Connect & Direct Routing

📌 Operator Connect – Enables CSPs to integrate PSTN directly within Teams for a seamless calling experience.
📌 Operator Connect Accelerator (OCA) – Fast-tracks deployment with certified vendors (e.g., Audiocodes, Ribbon, Nuwave, Sippio, Pingco).
📌 Direct Routing – Provides more control but requires SBC certification and compliance with Microsoft’s guidelines.

🔹 Cisco Webex: Cloud-Connected PSTN (CCP) & Local Gateway

📌 Cloud-Connected PSTN (CCP) – Enables PSTN providers to integrate directly with Webex Calling through certified providers (e.g., Audiocodes, Ribbon, Nuwave).
📌 Local Gateway – Supports on-premises telephony connectivity, requiring strict compliance with Cisco’s configuration standards.

🔹 Zoom One: Provider Exchange & BYOC

📌 Provider Exchange – Allows CSPs to integrate PSTN services directly into Zoom Phone.
📌 BYOC (Bring Your Own Carrier) – Permits CSPs to use their own SIP trunks, adhering to Zoom’s compliance and security requirements.

🔍 Compliance: Meeting UC Platform Standards

Strict compliance standards ensure interoperability and security but also add complexity for CSPs.

📌 Microsoft Teams – Operator Connect and Direct Routing require SBC certification and adherence to Microsoft’s security protocols.
📌 Cisco Webex – CCP and Local Gateway integrations must meet Cisco’s compliance, routing, and security requirements.
📌 Zoom One – Provider Exchange and BYOC require strict network security, session management, and performance standards.

By working within these frameworks, CSPs can ensure smooth integration, high-quality service, and reduced compliance risks.

🏗️ Local Gateways: A Critical Component for Business Migration

For businesses transitioning to cloud UC, local gateways act as enterprise-grade SBCs, bridging on-premises telephony and cloud UC platforms.

🔹 Key Benefits:
✔ Supports Phased Migrations – Businesses can retain PSTN while gradually moving to UC.
✔ Customisation & Compliance – Tailored for specific regulatory needs.
✔ Central Management – Easily managed within a Cloud Calling Platform.

📱 Mobile Integration: Teams Phone Mobile & Webex Go

Beyond traditional PSTN, mobile-first solutions like Teams Phone Mobile and Webex Go offer added flexibility.

📌 Teams Phone Mobile – Extends Teams calling features directly to mobile devices.
📌 Webex Go – Integrates Webex Calling with mobile native dialers via eSIM.

These solutions enhance mobility and simplify business communications.

🎯 Strategic Considerations for CSPs

🔹 Flexibility & Reach – Integrating across Teams, Webex, and Zoom One enables CSPs to serve diverse clients globally.
🔹 Marketplace Solutions vs Customisation – CSPs must balance pre-packaged solutions vs. bespoke integrations.
🔹 Hybrid Models & Local Gateways – Managed local gateways support hybrid UC environments.
🔹 International Locations – Partnering with global cloud calling solutions reduces infrastructure costs in multiple regions.

🌟 Navigating PSTN Integration for Success

In a competitive landscape, CSPs must balance flexibility, control, and compliance. By selecting the right PSTN integration approach, CSPs can deliver high-quality, scalable solutions for businesses of all sizes.

📩 CloudBoost works with global CSPs to enhance UC and CX services. Get in touch to learn more or schedule a briefing!