🚀 Building a Scalable UnifiedPBX CCaaS/UCaaS Architecture

┌──────────────────────────────────────────────────────────────────────┐
│                    UnifiedPBX CCaaS/UCaaS Platform                    │
├──────────────────────────────────────────────────────────────────────┤
│  Presentation Layer                                                   │
│  ┌────────────────────────────────────────────────────────────────┐ │
│  │  Frontend PWA (React) - Port 3000                              │ │
│  │  • Admin Dashboard  • Agent Interface  • Landing Pages         │ │
│  │  • Login/Register   • Call Control    • Real-time Analytics    │ │
│  └────────────────────────────────────────────────────────────────┘ │
├──────────────────────────────────────────────────────────────────────┤
│  API Gateway Layer                                                    │
│  ┌────────────────────────────────────────────────────────────────┐ │
│  │  API Gateway - Port 3001                                       │ │
│  │  • JWT Authentication  • Request Routing  • Rate Limiting      │ │
│  └────────────────────────────────────────────────────────────────┘ │
├──────────────────────────────────────────────────────────────────────┤
│  Microservices Layer                                                  │
│  ┌──────────────┬───────────────┬─────────────────┬──────────────┐ │
│  │ User Mgmt    │ CDR Service   │ App Control     │ Call Control │ │
│  │ Port: 3002   │ Port: 3003    │ Port: 3004      │ Port: 3005   │ │
│  │              │               │                 │              │ │
│  │ • Users      │ • CDR         │ • Campaigns     │ • Telephony  │ │
│  │ • Agents     │ • Billing     │ • Leads         │ • WebRTC     │ │
│  │ • Roles      │ • Reports     │ • Scripts       │ • Routing    │ │
│  │ • Auth       │ • Analytics   │ • Agent Groups  │ • Queues     │ │
│  └──────────────┴───────────────┴─────────────────┴──────────────┘ │
├──────────────────────────────────────────────────────────────────────┤
│  Telephony Integration Layer                                          │
│  ┌──────────────────────────────┬───────────────────────────────┐  │
│  │ Asterisk Integration         │ FreeSWITCH Integration        │  │
│  │ Port: 3007                   │ Port: 3006                    │  │
│  │ • AMI Connection             │ • ESL Connection              │  │
│  │ • ARI Integration            │ • Event Socket                │  │
│  │ • Config Sync                │ • Config Sync                 │  │
│  └──────────────────────────────┴───────────────────────────────┘  │
├──────────────────────────────────────────────────────────────────────┤
│  Data Layer                                                           │
│  ┌──────────────────┬────────────────────┬──────────────────────┐  │
│  │ PostgreSQL DB    │ Redis Cache        │ File Storage         │  │
│  │ Port: 5432       │ Port: 6379         │ (Recordings, Logs)   │  │
│  │                  │                    │                      │  │
│  │ • Users          │ • Sessions         │ • Call Recordings    │  │
│  │ • CDR            │ • Real-time Data   │ • Voicemail          │  │
│  │ • Campaigns      │ • WebSocket State  │ • Backup Files       │  │
│  │ • Config         │ • Rate Limits      │ • Documentation      │  │
│  └──────────────────┴────────────────────┴──────────────────────┘  │
├──────────────────────────────────────────────────────────────────────┤
│  Telephony Engine Layer                                               │
│  ┌──────────────────────────────────────────────────────────────┐  │
│  │  Asterisk PBX  │  FreeSWITCH  │  SIP Trunks  │  VoIP Providers │ │
│  │  • AMI/ARI     │  • ESL        │  • SIP       │  • Twilio       │ │
│  │  • Dialplan    │  • Sofia-SIP  │  • IAX2      │  • Others       │ │
│  └──────────────────────────────────────────────────────────────┘  │
└──────────────────────────────────────────────────────────────────────┘

I’m sharing the high-level architecture behind a UnifiedPBX platform designed for modern VoIP, Contact Center, and Unified Communications workloads.
The architecture is structured across multiple layers:
🖥️ Presentation Layer — React PWA for Admins, Agents, Call Control, and Real-time Analytics
🔐 API Gateway — JWT authentication, request routing, and rate limiting
⚙️ Microservices — User Management, CDR/Billing, Campaign & Application Control, and Call Control
📞 Telephony Integration — Dedicated services for both Asterisk (AMI/ARI) and FreeSWITCH (ESL/Event Socket)
🗄️ Data Layer — PostgreSQL for persistent data, Redis for real-time state and caching, plus file storage for recordings and logs
☎️ Telephony Engine — Asterisk, FreeSWITCH, SIP Trunks, and VoIP providers such as Twilio
The goal is to keep the platform modular, scalable, multi-tenant ready, and telephony-engine agnostic, allowing different services to evolve independently while maintaining centralized control and observability.
This approach provides a foundation for building:
• Cloud PBX
• Contact Center / CCaaS
• UCaaS
• WebRTC Calling
• IVR & ACD
• Outbound Campaigns
• Real-time Agent Monitoring
• CDR, Billing & Analytics
• AI Voice Agent integrations
The future of communications platforms is not just a PBX—it is an API-driven, event-driven, cloud-native communications ecosystem.
#UnifiedPBX #VoIP #CCaaS #UCaaS #CloudPBX #Asterisk #FreeSWITCH #WebRTC #SIP #Telecom #Telephony #ContactCenter #Microservices #SystemArchitecture #SoftwareArchitecture #React #NodeJS #PostgreSQL #Redis #API #SaaS #AI #VoiceAI #CallCenter #RealTimeCommunication #CommunicationPlatform

Originally published on a2cybertech.blogspot.com.