Netflow is a feature in IOS that allows network admins to see traffic information regarding their network. Here are the components of Netflow:
- Netflow Records – these are predefined or user defined key fields (such as source or destination IP address) for network monitoring.
- Flow monitors – these are applied to interfaces, flow monitors include records, a cache, and sometimes a flow exporter. The flow monitor cache collects information about flows.
- Flow exporters – these export the cached flows from the monitors to outside systems (usually some type of netflow collector)
- Flow samplers – these are designed to reduce the load on netflow devices by specifying the sample size of traffic, Netflow analyzes to a ratio of 1:2 through 1:32768 of the packets flowing across the interface.