C H A P T E R 1
Overview
This chapter describes the CNS NetFlow Collection Engine application, which is used with the NetFlow services data export feature on Cisco routers and Catalyst 5000 and 6000 series switches.
This chapter includes the following sections:
•What Are NetFlow Services?
•What Is CNS NetFlow Collection Engine?
•CNS NetFlow Collection Engine Architectural Overview
What Are NetFlow Services?
NetFlow services consist of
Because of their unidirectional nature, flows from a client to a server are differentiated from flows from the server to the client. Flows are also differentiated on the basis of protocol. For example, Hypertext Transfer Protocol (HTTP) Web packets from a particular source host to a particular destination host constitute a separate flow from File Transfer Protocol (FTP) file transfer packets between the same pair of hosts.
Routers and switches identify flows by looking for the following fields within IP packets:
•Source IP address
•Destination IP address
•Source port number
•Destination port number
•Protocol type
•Type of service (ToS)
•Input interface
Cisco CNS NetFlow Collection Engine User Guide, Release 5.0.2
|
| ||
|
|