Filecatalyst Detection Extra Quality

Most modern FileCatalyst deployments use TLS encryption. But the order is distinctive:

When a FileCatalyst client initiates a connection, it sends a specific handshake packet. filecatalyst detection

Pro tip: FileCatalyst often coexists with Aspera or Signiant in media networks. Don’t confuse the two — Aspera uses FASP‑UDP with a different initial window and congestion signature. Most modern FileCatalyst deployments use TLS encryption

Start detecting it today — not by port, but by behavior. Your network visibility will thank you. Don’t confuse the two — Aspera uses FASP‑UDP

This rule looks for the string "FileCatalyst" in the TCP stream heading to a destination port 21. While FileCatalyst may not broadcast its name in clear text in all modes, looking for specific SITE commands used by the software (often used for file verification) can trigger an alert.

Drop a comment or ping me directly — I’m happy to share the rule templates.

FileCatalyst supports FTPS (FTP over SSL/TLS) and HTTPS for API calls. If the traffic is encrypted, standard DPI fails.