Webinar Platform Development

Webinar Platform Development

Webinar platform combines video conference with audience management tools: registration, landing pages, interactivity (chat, Q&A, polls), recording and follow-up distribution. Key technical task — working with WebRTC and media servers to scale video stream to hundreds and thousands of participants.

Video Architecture

P2P (WebRTC without server): suitable only for 3–4 participants. With more — exponential load growth on each client.

SFU (Selective Forwarding Unit): media server forwards streams between participants without transcoding. Each participant sends one stream and receives from others. Scales to 50–200 participants.

MCU (Multipoint Control Unit): media server mixes all streams into one. Client load minimal, suitable for thousands viewers, but high server load.

CDN streaming (HLS/DASH): host streams to RTMP → server transcodes to HLS → CDN distributes to viewers. 5–30 second delay, unlimited scale.

For webinar format (1 host + thousands viewers): SFU + CDN streaming for scale-out.

Media Servers

Livekit — open-source SFU on Go, actively developed. SDK for React, Vue, iOS, Android. Supports ingress (RTMP, HLS input). Hosting: self-hosted or Livekit Cloud.

import { Room, RoomEvent } from 'livekit-client';
const room = new Room();
await room.connect('wss://yourinstance.livekit.cloud', token);
await room.localParticipant.enableCameraAndMicrophone();

Mediasoup — low-level SFU library Node.js, requires more development, maximally flexible.

Agora / Daily.co / Vonage — managed services, payment per minutes, quick integration, less control.

Webinar Lifecycle

Creation → Setup → Promo page
→ Participant registration → Email reminders
→ Stream start → Interactivity (chat, Q&A, polls)
→ End → Recording processing
→ Send recording → Analytics

Registration and Participant Management

Landing page: topic, date/time with timezone, speakers, program, registration form. After registration — confirmation email with join link (unique token, no password required).

Reminders: 24 hours before, 1 hour before, 15 minutes before. Integration with Google Calendar / Outlook via .ics file.

Host Tools

• Screen sharing — via WebRTC getDisplayMedia()
• Whiteboard — collaborative board (Excalidraw-compatible component)
• Slides — presentation via iframe or PDF-viewer
• Hand raise — viewer signals question
• Spotlight — highlight participant (bring from viewers to stage)
• Breakout rooms — split into rooms (for workshops)

Recording and Processing

After webinar ends, recording processed:

1. Media server delivers raw recording (MP4 or WebM)
2. FFmpeg transcodes to optimal format with different resolutions
3. Uploads to Cloudflare Stream or Mux
4. Sent to participants (and unregistered if needed)

Webinar Analytics

• Peak concurrent presence
• Retention: when participants left (% remaining each moment)
• Engagement: chat activity, poll responses
• Conversion: registrations → visitors → completed viewing

Timeline

MVP (landing, registration, webinar room with chat, recording, distribution): 3–4 months. Full platform with multiple speakers, breakout rooms, analytics, CRM integration: 5–8 months.