NETFLOW-MIB

The Netflow MIB provides a simple and easy method to get NetFlow cache information, current NetFlow configuration and statistics. It will enable medium to small size enterprises to take advantage of NetFlow technology over SNMP at a reduced infrastructure cost. The MIB is created to provide Netflow information in these areas: 1. Cache information and configuration. 2. Collector information and configuration. 3. Export Statistics. 4. Version 9 Export Template information. Terminology used Flow A flow is defined as a unidirectional sequence of packets with some common properties that pass through a network device. These collected flows are exported to an external device, the NetFlow collector. Network flows are highly granular; for example, flow records include details such as IP addresses, packet and byte counts,timestamps, Type of Service (ToS), application ports, input and output interfaces, etc. Exporter A device (for example, a router) with NetFlow services enabled. The exporter monitors packets entering an observation point and creates flows out of these packets. The information from these flows are exported in the form of Flow Records to the collector. Flow Record A Flow Record provides information about an IP Flow that exists on the Exporter. The Flow Records are commonly referred to as NetFlow Services data or NetFlow data. Collector The NetFlow Collector receives Flow Records from one or more Exporters. It processes the received export packet, i.e. parses, stores, display the Flow Record information. The flow records may be optionally aggregated before being stored into the hard disk. Template NetFlow Version 9 Export format is template based. Version 9 record format consists of a packet header followed by at least one or more template or data FlowSets. A template FlowSet (collection of one or more template) provides a description of the fields that will be present in future data FlowSets. Templates provide an extensible design to the record format, a feature that should allow future enhancements to NetFlow services without requiring concurrent changes to the basic flow-record format. One additional record type is also a part of Version 9 specification: an options template. Rather than supplying information about IP flows, options are used to supply information about the NetFlow process configuration or NetFlow process specific data.