🎯 Project Overview

Designed and deployed a production-grade, cloud-based PBX system using Asterisk with MySQL Realtime architecture, enabling dynamic configuration without service restarts. The system features browser-based WebRTC softphones with secure WSS signaling, making it accessible from anywhere without installing client software.

💼 Business Impact

Zero-downtime provisioning: Add/modify extensions instantly without PBX reload
Reduced client costs: Eliminated need for physical desk phones and software licenses
Multi-tenant ready: Single infrastructure serving multiple organizations securely
Global accessibility: Employees can make/receive calls from any device with a browser
99.9% uptime: High-availability configuration with automated failover

🛠️ Technical Architecture

Core Technologies

Asterisk 20.x - Core PBX engine with PJSIP stack
MySQL 8.0 - Realtime configuration database
WebRTC - Browser-based calling (DTLS-SRTP encryption)
WSS (Secure WebSockets) - Encrypted signaling on port 8089
Laravel 11 - Admin portal for provisioning and management
Let's Encrypt - Automated SSL certificate management
Kamailio - SIP proxy for load balancing (multi-server setup)

Key Features Implemented

✅ Real-Time Configuration

All SIP endpoints, authentication, and routing stored in MySQL. Changes reflect instantly—no asterisk reloads needed.

✅ WebRTC Softphone Integration

Browser-based calling using JsSIP library. Users log in to web portal and make calls directly—no downloads required.

✅ Multi-Tenant Architecture

Isolated contexts per client with dedicated DIDs, extensions, and routing rules. Single server infrastructure, multiple organizations.

✅ Advanced Call Routing

Time-based routing, IVR menus, queue management, voicemail-to-email, and automatic call distribution.

🔧 Technical Challenges Solved

NAT Traversal for WebRTC

Challenge: WebRTC clients behind different NAT types couldn't establish media connections.

Solution: Configured STUN/TURN servers (coturn), implemented ICE candidate gathering, and properly set external_media_address in Asterisk.

SSL Certificate Management

Challenge: WebRTC requires HTTPS/WSS. Managing certificates for multiple client domains was complex.

Solution: Automated Let's Encrypt integration with wildcard certificates and cron-based auto-renewal. Built certificate deployment system in Laravel.

Database Connection Pooling

Challenge: High call volume caused MySQL connection exhaustion.

Solution: Implemented connection pooling in Asterisk res_odbc, optimized queries with proper indexes, and added read replicas for scalability.

📊 Performance Metrics

500+

Concurrent Calls

<100ms

Call Setup Time

99.9%

Uptime SLA

2000+

Registered Users

💡 Innovations

API-First Design: RESTful API for programmatic provisioning—integrated with CRM systems
Real-Time Dashboard: Live call monitoring via AMI + WebSockets showing active calls, queue stats, agent status
Automated Backup: Hourly database snapshots with point-in-time recovery capability
CDR Analytics: Call detail records processed into business intelligence dashboards
Emergency Failover: Automated detection and routing to backup server in <30 seconds

🚀 Results

✅ Deployed to 15+ organizations across healthcare, finance, and e-commerce
✅ Handling 50,000+ calls/month with zero-downtime maintenance
✅ Reduced client telecommunications costs by 60-70% vs traditional PBX
✅ Enabled remote work during pandemic with browser-based calling
✅ Integrated with CRM systems (Salesforce, HubSpot) for click-to-dial

🔗 Related Content

Read the full technical deep-dive: Building Realtime Asterisk PBX with MySQL and WebRTC

Asterisk Realtime PBX with WebRTC Softphone