Complete File Control.
Automatic Enforcement.

Upload once. Set your rules. DGR enforces download limits, device locks, and time restrictions automatically—no recipient software required.

Three-Layer Protection System

DGR combines server-side tracking, device fingerprinting, and file-level encryption to create an unbreakable protection chain.

🔐

Server Tracking

Every download is logged with device fingerprint, IP address, and timestamp. The server enforces your copy limit before serving any file.

📱

Device Locking

Each unique device can download once. Files are bound to device fingerprints using AES-256 encryption—making link sharing impossible.

⏱️

Time Limits

Set expiration times (hours or days). Files become permanently inaccessible after the deadline—even if already downloaded.

How File Protection Works

1

You Upload and Configure

Upload any file type. Set your download limit (1-1000+), enable watermarking, and optionally enable device locking with expiration time. DGR encrypts your file with AES-256-GCM and generates a unique share link.

2

You Share the Link

Send the link via email, Slack, or any channel. The link works for anyone—no login required. But DGR tracks every download attempt with device fingerprinting (IP + browser signature + MAC address hash).

3

First Downloads Get Tracked Copies

Each new device gets a functional, lightly watermarked copy with a unique copy number (e.g., "Copy 3 of 50"). The watermark is subtle—images get a small badge, documents get a header comment, models get metadata tags. Files work perfectly.

4

Duplicate Device Attempts Get Corruption

If someone tries to share their link with a friend, the friend's device is flagged as "duplicate" and receives a completely corrupted file—even if the limit isn't reached yet. This makes link sharing worthless.

5

After Limit: Total Corruption

Once you've hit your download limit (e.g., 50/50), every subsequent download receives a file that's corrupt at the binary level. Images show error screens, PDFs display access-denied notices, AI models have NaN-poisoned weights, videos show static. The corruption is permanent and irreversible.

6

You Always Get the Original

As the owner, you can download unlimited times and always receive the pristine original file. You can also grant explicit access to specific colleagues by email—they bypass all limits.

💡 Key Insight

The protection happens server-side. Recipients need zero software, extensions, or apps. They click the link, download the file, and open it normally. The enforcement is invisible until someone tries to exceed your limits.

Device Locking in Detail

DGR uses a multi-factor device fingerprint to create unique device IDs:

  • IP Address: Primary network identifier (first segment only to allow mobile switching)
  • User Agent: Browser + OS + version string
  • Network MAC Hash: SHA-256 hash of network hardware addresses (when available)
  • Server Salt: Combined with your encryption key for uniqueness

This creates a fingerprint like: 7f3a9d2e8b4c1f6a...

Real-World Example:

Alice downloads your file on her MacBook (Device A). She shares the link with Bob. Bob tries to download on his Windows PC (Device B). Bob's device fingerprint doesn't match Device A, so Bob receives a corrupted file—even if only 1 of 100 copies have been used. This prevents link sharing entirely.

Permission Grants: Bypass All Limits

Grant explicit access to specific people by email. They bypass device locks and copy limits entirely.

Permission Level
What They Get
Owner
Full access rights
✓ Original file always
✓ Unlimited downloads
✓ No device restrictions
View
Limited access rights
✓ Original file once
○ Configurable download limit
○ Optional expiration date
Public Link
No explicit permission
✗ Watermarked copy
✗ Subject to copy limit
✗ Device-locked

Use case: Grant "owner" permission to your engineering team (10 people). They all get unlimited access to the original file. Everyone else who gets the public link receives watermarked, device-locked copies subject to your 50-download limit.

File-Type Specific Corruption

When limits are exceeded, DGR applies intelligent corruption that preserves file format validity but destroys usability:

File Type Corruption Method Result
Images
JPG, PNG, WebP
Replace pixels with noise + error overlay using Sharp library Image opens but shows static noise + "UNAUTHORIZED ACCESS" text overlay
PDFs
Adobe PDF
Generate valid PDF with single page showing access-denied notice PDF opens in reader but only shows "UNAUTHORIZED ACCESS" message
Videos
MP4, MOV, AVI
Keep container header, replace video frames with noise Video player opens but shows corrupted/glitched frames
Audio
MP3, WAV, M4A
Replace audio samples with harsh alternating square waves File plays but outputs loud static/noise
AI Models
PyTorch, Safetensors, GGUF
Keep model structure, replace all weights with IEEE 754 NaN values Model loads in framework but produces only NaN outputs—completely unusable
Code
JS, PY, TS, C++
Replace contents with garbage code + error comments File opens but contains random gibberish and "FILE CORRUPTED" comments
Documents
DOCX, TXT, MD
Replace content with "UNAUTHORIZED ACCESS" message Document opens but contains only access-denied text
🔬 Technical Deep Dive

The corruption is permanent and irreversible. We don't encrypt or obfuscate—we physically destroy the data at the binary level. There's no "uncorrupt" function, no recovery tool, no workaround. The file's content is gone forever.

Real-World Use Cases

For Individuals & Small Teams

🎨 Freelance Designers

Send client previews with 3-download limit. Clients can review on their devices, but can't share with unauthorized parties. You control distribution.

💼 Job Applications

Share your portfolio or resume with 10-download limit. Track which companies accessed it and prevent unlimited redistribution of your work.

📸 Photographers

Send photo proofs to clients with copy limits. They can't share the full-res files with friends or use them without paying for rights.

🎓 Course Creators

Distribute course materials with student-specific device locks. Each enrolled student gets one copy—no sharing or piracy possible.

For Enterprises

🏢 Confidential Documents

Share board reports or financial data with 20-person limit. Each executive gets tracked access. After the board meeting, further downloads are corrupted.

🔬 Research & IP

Distribute research papers or patent applications to 50 reviewers. Track every access. Prevent leaks to competitors or press.

🤖 AI Model Distribution

Share fine-tuned models with enterprise clients. Set 100-download limit for their team. Beyond that, model weights are NaN-poisoned and unusable.

📋 Due Diligence

Send sensitive documents to potential investors with time limits. Files expire 48 hours after the call. No long-term exposure risk.

Encryption & Security Stack

At Rest

AES-256-GCM Unique per-file keys Encrypted PostgreSQL Key isolation

In Transit

TLS 1.3 HSTS enforced Certificate pinning Secure file uploads

Authentication

Bcrypt (12 rounds) JWT tokens API keys SHA-256 hashing

Infrastructure

SOC 2 Type II DDoS protection Rate limiting WAF

Ready to Protect Your Files?

Start with 2 free file uploads. No credit card required.

Get Started Free View Documentation