How First Packet Classification (FPC) Works in nDPI
Starting with nDPI 4.10, we have introduced a new feature called First Packet Classification (FPC). Goal of this technique is to address one problem of DPI that detects a protocol only when traffic has been dissected. This means that for TLS you need a few packets (usually between 5 and 10) for protocol dissection, as nDPI has to wait until TLS handshake packets are exchanged. This can be a problem in particular when DPI is used with inline traffic (e.g. on a IPS) as the decision about the application protocol …
