What is Netflow/IPfix ?

NetFlow provides the ability to collect IP network information as it enters or exits an interface. A Flow Record consists of keyed fields and non-keyed fields. Keyed fields are all field(s) which need to be unique in order for a new Flow Record cache entry to be created in the CPE memory. Non-keyed fields provide information such as metrics (byte count, packet count, latency or jitter). For every record, a cache table is created to track and store flow entry. A new cache entry is created when the keyed field(s) of the packet does not match existing cache entry. Otherwise, only the non-keyed fields are updated, e.g. byte count is incremented.