NetFlow is a UDP -exported network profiling protocol originally developed by Cisco Systems in 1996. It enables participating devices (typically routers and switches) to report telemetry data on the network traffic flowing through them (such a device is called a NetFlow exporter). This data is sent to a downstream machine, called a NetFlow Collector:
The data can then be
collated, sorted, analyzed, trended, and so on. The most widely
deployed version of NetFlow, version 5, offers the capability to
track the following flow data (the traditional Cisco 7-tuple is
highlighted in blue):
NetFlow version 9 introduced much more power with
the capability to dynamically change the packet format using
templates and match on just about anything using Flexible Netflow.
If packet capture can be thought of as a wiretap,
Netflow can be considered the phone bill. NetFlow allows the Network
Administrator and Security Practitioner to determine:
- Who is talking to who
- Over what ports (or protocols)
- For how long
- At what speed
To know more about
networking protocols, you can join networking courses at SLA IT
Employment Training Company. For
more details visit Cisco IOS NetFlow - Cisco Certified Netowrk Adminstrator (CCNA) Training Institute or dial +91 86818 84318.
