P2P Communication's Serverless Myth | Generated by AI
Great question! You’re connecting the right dots between peer-to-peer (P2P) principles and modern communication apps, but there’s a crucial distinction: PPP (Point-to-Point Protocol) operates at the data link layer (Layer 2) for direct serial/modem connections, while applications like RustDesk or web3 chats run at the application layer (Layer 7) using different P2P techniques.
Here’s the reality check on “serverless” real-time communication:
The “Serverless” Myth: Why Pure P2P is Hard
While WebRTC and other P2P technologies do enable direct connections, calling them “serverless” is misleading. You still need:
1. Signaling Servers (Mandatory)
Before peers can connect directly, they must exchange metadata (IP addresses, encryption keys, session descriptions). This requires a temporary “meeting point” server. RustDesk uses this for ID/PW exchange, and WebRTC apps need signaling channels like WebSockets.
2. NAT Traversal Infrastructure (Practically Mandatory)
Most devices are behind NATs/firewalls. UDP hole punching can establish direct connections, but it has critical limitations:
- Works: For cone NATs when both peers coordinate simultaneous outbound packets
- Fails: With symmetric NATs (common in mobile/corporate networks) which assign unpredictable ports
- Requires: STUN servers to discover public addresses and coordinate the “punch”
3. TURN Relay Servers (Essential Fallback)
When hole punching fails (30-50% of cases), you must have a relay server (TURN) that forwards encrypted traffic. Without this, your app simply won’t connect for many users.
RustDesk Reality: Not Pure P2P
RustDesk’s “P2P” is actually:
- Direct mode: Attempts UDP hole punching for direct connection
- Relay fallback: Self-hosted server acts as TURN relay when direct fails
- Self-hosting: You control the infrastructure, but infrastructure is still required
Web3 Messaging: Promising but Not Problem-Free
Apps like Secretum (Solana-based), DMail, or Matrix do offer decentralized chat:
✅ Advantages
- Wallet-based identity: No phone numbers/emails required
- End-to-end encryption: XMTP protocol encrypts messages
- Federation: Matrix servers can interconnect like email
- Censorship-resistant: No single point of failure
❌ Challenges
- Scalability: Pure P2P mesh networks break down with >4-6 participants (exponential bandwidth growth)
- Reliability: Message delivery isn’t guaranteed without persistent servers
- Mobile battery: Constant P2P connections drain devices
- NAT traversal: Same STUN/TURN problems as any P2P system
- Storage: Where do offline messages live? Requires decentralized storage (IPFS, etc.)
Architecture Patterns: Choose Your Tradeoff
| Pattern | Server Needed | Scalability | Use Case |
|---|---|---|---|
| Pure P2P Mesh | Only signaling | ✗ Poor (>6 users) | 1-1 calls, small groups |
| SFU (Selective Forwarding) | Self-hosted server | ✓ Good (100s) | Meetings, live streams |
| MCU (Multipoint Control) | Heavy server | ✓ Excellent (1000s) | Large conferences |
| Web3 + Federation | Federation servers | ✓ Moderate | Public chat, communities |
The Verdict: Can It Be the Future?
Partially yes, but with caveats:
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For 1-1/small groups: Yes, with self-hosted signaling & TURN. Tools like Jitsi Meet (self-hosted SFU) + Matrix (federated) get you 90% there.
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For large meetings: Pure P2P is impossible. You need SFU/MCU servers. The “serverless” dream breaks down at scale.
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For web3 identity: Already happening. XMTP, Matrix, and wallet-based auth work today, but they complement rather than eliminate infrastructure.
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For true decentralization: Emerging. Protocols like QUIC-based P2P aim to improve hole punching, but widespread symmetric NAT support remains unsolved.
Bottom Line
You can build open-source, self-hosted, encrypted communication that minimizes central servers, but eliminating them entirely creates unreliable, unscalable apps. The future is likely hybrid: P2P where possible, self-hosted relays where necessary, and blockchain for identity/storage—not as a complete server replacement.