FastFileLink Technical FAQs

What is P2P (Peer-to-Peer) or "Directly Share" in FastFileLink?

P2P, or Peer-to-Peer, is a method of sharing files directly between two computers over the internet without needing to upload the file to a central server first. When you use FastFileLink's "Directly share file (P2P) by local" option, your computer connects directly to the recipient's computer.
This process often utilizes web technologies like WebRTC (Web Real-Time Communication), which enables browsers and applications to establish direct communication channels. This means the file data travels from your device to the recipient's device, making the transfer potentially faster and more private as it doesn't rely on an intermediary server storing the file.

For more information on WebRTC, you can visit the WebRTC project website or its Wikipedia page.

What is Relayed P2P? How does FastFileLink handle connection issues?

Sometimes, a direct P2P connection isn't possible. This can happen due to network configurations like certain types of NAT (Network Address Translation) or restrictive firewalls/ports that block direct connections.
In such cases, FastFileLink uses a fallback mechanism called Relayed P2P. Instead of your file going through a generic WebRTC TURN server, FastFileLink will use its own dedicated relay server. This server acts as a go-between:

• It uses port 443, the standard port for HTTPS/SSL traffic. This port is rarely blocked, ensuring a very high connection success rate even in restricted network environments.
• The relay server only forwards data (socket-to-socket) between your computer and the recipient's.
• Crucially, our relay server does not store any intermediate data or your files. It also keeps no logs of the transfer content, ensuring your privacy is maintained during the relay process.

What is NAT (Network Address Translation) and how does it affect FastFileLink?

NAT (Network Address Translation) is a method used by routers to allow multiple devices on a private network (like your home or office) to share a single public IP address when accessing the internet. You can think of it as a receptionist for your network, directing internet traffic to the correct device.

For more details, see the Wikipedia article on NAT. While NAT is essential, it can sometimes make direct P2P connections tricky because devices are hidden behind this shared IP. Technologies like WebRTC (used in our P2P sharing) have built-in mechanisms (like STUN/ICE) to discover the public IP address and attempt to establish direct connections even through many types of NAT. However, some NAT configurations are more restrictive. This is where FastFileLink's Relayed P2P feature becomes vital. By using our relay servers on port 443, we can achieve a very high connection reliability (e.g., around 99.9%), bypassing most NAT-related P2P connection issues.

What is "Resuming Download" or Continuation Transfer?

FastFileLink supports resuming downloads. This means if your file download gets interrupted (for example, due to a temporary loss of internet connection), you or your recipient won't have to start the download all over again. Once the connection is restored, the download can pick up from where it left off, saving time and bandwidth.

How does FastFileLink handle privacy and file security?

We prioritize your privacy and the security of your files:

• During Direct P2P or Relayed P2P transfers: The connection established for transferring data is encrypted. For Relayed P2P, as mentioned, our relay servers do not store your files or log transfer contents. The link generated for sharing is also protected by a random code, making it difficult for attackers to guess or use brute-force methods to access your download link.

• When using Server Upload Mode: If you choose to upload your file to the FastFileLink server, the connection for uploading and downloading the file is encrypted. Files stored on our servers are for the temporary retention period you select. While the files are on our servers, they are protected by our storage protocols. Expired or failed uploaded files are periodically removed from the server.

• Application Security: The FastFileLink application itself is designed to be safe. It has passed most general antivirus detections. We guarantee that our application does not contain malware or malicious code. If you encounter warnings from security software like Microsoft Defender SmartScreen, it's often because each user's application may have unique identifiers not yet recognized as frequently downloaded software.