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Network address translation, Allen-bradley products that support nat – Rockwell Automation Ethernet Design Considerations Reference Manual User Manual

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Rockwell Automation Publication ENET-RM002C-EN-P - May 2013

Chapter 3

Ethernet Infrastructure Features

Network Address Translation

Network address translation (NAT) enables a single device to act as an agent
between the public network (commonly the plant network) and the private
network (machine network). This facilitates communication between a group of
computers with preset IP addresses on a private network by mapping each preset
IP address to a valid IP address on the public network.

These are two types of NAT implementations:

One-to-many—Multiple nodes are mapped to a single public identity to
get onto the Internet, such as in a home network. This type of
implementation conserves public IP addresses and offers some protection
against attacks from the Internet.

One-to-one—Each node on the network translates to another identity on
another network. This type of implementation is used in manufacturing to
integrate machinery onto a larger network without requiring addressing
changes at the machine level.

Allen-Bradley Products That Support NAT

The table summarizes features of the two products that support one-to-one NAT.

Feature

9300-ENA Device

Stratix 5700 Switch

NAT architecture

Standalone device

Integrated into switch hardware

Performance

500 messages/s

Wire-speed translations

Number of translations, max

128

128 devices or subnets

(1)

(1) One subnet translation can include translations for 16…65,000 devices.

Supported network topologies

Star

Star
Redundant star
Ring

Configuration

Web interface

Device Manager Web interface
Studio 5000 environment
Command-line interface (CLI)