System Compatibility

Network Storm Protection Features

Packet rate limiting – the Smart Switch is configured with

a fixed rate packet limiting setting. The switch rate limiting

prevents network communication storms generated from

broadcast, multicast, and unknown unicast messages from

impacting DeltaV communications by blocking excessive

traffic. These types of excess traffic can occur naturally as part

of the traffic generated by Ethernet communications. Storm

protection is enabled to protect the network during system

maintenance activities, redundancy switchovers, and during

times when the system is performing routine network activities

where excess network traffic is possible.

Network Loop protection – spanning tree protocol is

implemented on the Smart Switch to prevent a network loop

from creating a network communication storm.

These storm protection features are enabled by default and

cannot be disabled or configured. Storm protection is enabled

even if the switch is not given an IP address for management.

These features are completely compatible with older DeltaV

Smart Switches. Existing switches can be field upgraded to use

these new features if desired.

Please see the general specifications section for specific

firmware version numbers.

Important note: Network storm protection and loop

protection are available only on managed switches. Therefore,

DeltaV control networks using Electronic Marshalling require a

Smart Switch installed between the DeltaV controller and CIOC.

This network configuration reduces the risk of a network storm

disrupting communications and causing the CIOC to go to a

fail-safe mode.

Please refer to DeltaV Books-On-Line and the v13.3 System

Planning Guide for more information and requirements for

implementing the DeltaV Area Control Network with

Electronic Marshalling.