# Validators

## What is a Validator?

A validator is an independent node operator who runs a relay server that powers the Zentalk network. Validators route encrypted messages between users, store encrypted data chunks, and participate in peer discovery — all without being able to read any of the content they handle.

The Zentalk network has no central server. Instead, it relies on a distributed mesh of validator nodes operated by independent participants around the world. The more validators join the network, the more resilient, private, and censorship-resistant it becomes.

{% hint style="info" %}
Validators handle only encrypted data. Even a malicious validator cannot decrypt messages, read files, or identify who is communicating with whom.
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## What Validators Do

Each validator node performs three core functions simultaneously:

### Message Relay

The relay module routes encrypted messages between users in real-time. When a recipient is offline, messages are queued in an encrypted store and delivered when they reconnect. All routing uses 3-hop onion encryption — no single relay knows both the sender and recipient of any message.

### Mesh Storage

The storage module holds encrypted data chunks distributed across the network using Reed-Solomon erasure coding. Files are split into shards and spread across multiple validators, ensuring data survives even if some nodes go offline. Validators store these shards without the ability to reconstruct or read the original data.

### Peer Discovery

The DHT (Distributed Hash Table) module enables validators to find each other and new users to discover available nodes. This uses the Kademlia protocol via libp2p, with automatic health monitoring and recovery. Validators also participate in GossipSub for network-wide announcements.

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## Why Run a Validator

* **Earn Rewards** — Validators earn CHAIN tokens for relaying messages and providing storage services to the network
* **Support Privacy** — Every validator strengthens the decentralized network, making surveillance and censorship harder
* **Low Barrier** — A single binary deployment with Docker support, no complex infrastructure required
* **Full Monitoring** — Built-in Prometheus metrics, health endpoints, and support for Grafana dashboards
* **Open Participation** — Anyone can join as a validator, no permission required

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## How It Works

### Server-Blind Architecture

Validators operate on a "lockbox" principle. They receive, store, and forward encrypted blobs — but they never hold the keys to decrypt them. This is enforced by cryptography, not policy:

* Message content is encrypted with Signal Protocol before it ever reaches a validator
* Routing information is wrapped in 3 layers of onion encryption (RSA-4096 per layer)
* Group membership is hidden through Sealed Fanout delivery
* Storage chunks are encrypted with AES-256-GCM before sharding

Even if a validator operator inspects every byte passing through their node, they see only encrypted data with no way to determine its contents or link senders to recipients.

### Federation

Validators automatically discover each other through the DHT network. When a user connected to one validator sends a message to a user on a different validator, the message is forwarded between relays using TLS with mutual authentication and certificate pinning.

The network uses weighted relay selection to optimize routing:

| Strategy   | Priority                                 | Best For                |
| ---------- | ---------------------------------------- | ----------------------- |
| Balanced   | Latency, capacity, reputation, geography | General messaging       |
| Latency    | Lowest response time                     | Voice and video calls   |
| Capacity   | Most available storage                   | File sharing            |
| Reputation | Highest reliability score                | Critical communications |

### Self-Healing

The network automatically handles node failures:

* Disconnected peers are retried with exponential backoff
* Degraded storage shards are automatically repaired by the anti-entropy service
* Routing tables are refreshed every 10 minutes
* Unhealthy nodes are temporarily excluded from relay selection

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## Network Security

Validators are hardened with multiple security layers:

| Protection           | Implementation                                          |
| -------------------- | ------------------------------------------------------- |
| Transport Encryption | TLS 1.3 + Noise Protocol for all node communication     |
| Anti-Sybil           | Peer scoring (100 points baseline, disconnect below 20) |
| Subnet Diversity     | Max 3 peers per IPv4 /24 to prevent eclipse attacks     |
| Rate Limiting        | 3-layer: per-IP, per-address, and ZKP-based (RLN)       |
| Replay Prevention    | Nonce tracking with 45-second timestamp window          |
| DDoS Protection      | 10K connection limit with load shedding                 |
| Membership Tokens    | Ed25519 signed tokens with epoch-based revocation       |

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## Node Capacity Management

Validators automatically manage their resources:

| Capacity | Status    | Behavior                    |
| -------- | --------- | --------------------------- |
| 0–70%    | Healthy   | Accept all writes           |
| 70–80%   | Warning   | Accept writes, log warnings |
| 80–90%   | Degraded  | Reject large files          |
| 90–95%   | Critical  | Serve existing users only   |
| 95–100%  | Emergency | Reject all new writes       |

The network routes around overloaded validators automatically, ensuring consistent service quality.

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## Resilience Testing

The validator software is tested against **49+ chaos engineering scenarios** including:

* Network partitions and split-brain conditions
* Node failures and unexpected restarts
* Storage corruption and disk pressure
* Certificate expiration and key rotation failures
* Memory pressure and resource exhaustion

This ensures the network remains operational under real-world failure conditions.

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## Performance

Benchmarked on Apple M3 Pro:

| Operation                   | Throughput          |
| --------------------------- | ------------------- |
| Message relay               | 1,000+ messages/sec |
| Storage writes              | 100+ MB/s           |
| 3-hop routing latency (p95) | < 100 ms            |
| Concurrent connections      | 10,000+ per node    |
| AES-256-GCM encryption      | 590,000 ops/sec     |

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## Getting Started

The Zentalk validator program is currently in development. If you are interested in running a validator node, visit [zentalk.chat](https://www.zentalk.chat/) for the latest information on the validator program, requirements, and how to participate.

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Running a validator requires staking CHAIN tokens and meeting minimum hardware requirements. Full details, staking contracts, and setup instructions will be available at [zentalk.chat](https://www.zentalk.chat/) when the validator program opens.
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