File Sharing

KayakNet supports sharing files through the chat system and marketplace.

Current Capabilities

Images in Chat

Share images directly in chat:

1. Click the image icon in chat

2. Select file from device

3. Image is encrypted and sent

4. Recipient sees inline preview

Supported formats:

• JPEG/JPG

• PNG

• GIF

• WebP

Size limit: 5MB per image

Marketplace Images

Listings can include product images:

• Main image (required)

• Up to 5 additional images

• Compressed for network efficiency

How It Works

Image Encoding

1. User selects image
   │
2. Image resized (max 1920x1080)
   │
3. Compressed to JPEG (quality 85%)
   │
4. Base64 encoded
   │
5. Encrypted with room/recipient key
   │
6. Sent via standard message

Delivery

• Small images (<100KB): Inline in message

• Large images: Chunked delivery

• DHT: Store-and-forward for offline

Planned Features

Full File Sharing (Coming Soon)

Share any file type:

• Documents (PDF, TXT, etc.)

• Archives (ZIP, TAR)

• Media (video, audio)

• Any binary file

Distributed Storage

Large files will be:

1. Split into chunks

2. Encrypted per-chunk

3. Distributed across DHT

4. Retrieved on demand

BitTorrent Integration

For large files:

• Create KayakNet torrents

• Share magnet links in chat

• Download via P2P within network

Security

Encryption

All files are encrypted:

• Room files: Room symmetric key

• DM files: Recipient's public key

• Marketplace: Public (for listings)

Metadata

File metadata is also protected:

• Filename (optional to share)

• Size (padded)

• Type (not leaked)

Best Practices

1. Don't share sensitive files - Unless absolutely necessary

2. Verify recipients - Ensure intended audience

3. Delete after use - Clear from local storage

4. Check file sizes - Large files may be slow

Limitations

Current Limitations

Limitation	Value
Max image size	5MB
Max images per listing	6
File types	Images only

Network Constraints

• Large files strain onion routing

• Slow on mobile connections

• DHT storage is temporary

API

Upload Image (Chat)

POST /api/chat/upload
Content-Type: multipart/form-data

file: <image data>
room: #general

Get Image

GET /api/chat/file?id=file_abc123

Marketplace Image

POST /api/market/create
{
  "images": ["data:image/jpeg;base64,..."]
}