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Rockwell Automation Publication 1783-UM007I-EN-P - December 2017 159
Configure Switch Features Chapter 3
NetFlow Lite NetFlow Lite is available on Stratix 5400 and 5410 switches. NetFlow Lite uses
flows to provide statistics for accounting, network monitoring, and network
planning. A flow is unidirectional stream of packets that arrives on a source
interface and has the same values for the keys. A key is a value for a field within
the packet. You create a flow by using a flow record to define the unique keys
for your flow.
There are two primary methods to access NetFlow data:
•
The command-line interface (CLI)—Use show commands to view data
and troubleshoot.
•
An application reporting tool—Export flows to a reporting server,
known as a NetFlow collector. The NetFlow collector uses the flows to
produce reports for traffic and security analysis.
For more information about using NetFlow Lite, refer to documentation
available at
http://www.Cisco.com .
Network Address Translation
(NAT) For a list of switches that support NAT, see page 16 .
NAT is a service that translates one IP address to another IP address via a
NAT-configured switch. The switch translates the source and destination
addresses within data packets as traffic passes between subnets.
This service is useful if you reuse IP addresses throughout a network. NAT
enables devices that share one IP address on a private subnet to be segmented
into multiple identical private subnets while maintaining unique identities on
the public subnet.
(1)
The implementation of NAT in Stratix switches is distinct in these ways:
•
One-to-one NAT—The switch uses one-to-one NAT, rather than
one-to-many NAT. One-to-one NAT requires that each source address
translates to one unique destination address. Unlike one-to-many NAT,
multiple source addresses cannot share a destination address.
•
Layer 2 implementation—The implementation of NAT operates at the
Layer 2 level. At this level, the switch can replace only IP addresses and
does not act as a router.
See also the Stratix 5700 NAT Whitepaper, publication ENET-WP032 .
(1) The terms private and public differentiate the two networks on either side of the NAT device. The terms do not mean that the
public network must be Internet routable.