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Why Industrial Managed Switch?

Industrial Unmanagedswitches have been used forbasic network connectivity in industrial networks. Although they are available withfeatures such as redundant power inputs, wider operating temperature, and other hardware features that can be very important to applications but do not provide software features that are offered by managed switches.
Industrial managed switches providesoftware features to increase performancand determinism to an Ethernet network by like features of QoS, IGMP Snooping, Redundancy, VLANs, and Traffic Monitoring.  QoS or Quality of Service provides the ability to prioritize network traffic.
QoS increases determinismby ensuring that high-priority trafficis passed through first.For example, framesto and from a motion controller would be processed before traffic to and from other devices
IGMP Snooping provides smart routingof Multi-cast traffic.Thereare three types of transmissions over an IP network - Broadcast,Uni-cast, and Multicast.Broadcasttraffic is data that is sent out to all devices on the network. Uni-cast messageare messagesintended for one device, whereas multicast messages are packetssent to a predefined group ofdevices.Routers are aware of multicast messages beingpassed to and from the internet, orothers networks, making multicast messaging more efficient than Uni-cast messaging.However, Switches are not aware of multicast traffic unless the IGMP snoopingprotocol is implemented.Without IGMP snooping, these messages become broadcast messagesto impact and decrease network performances or even to bring network down.
Redundancy reduces or eliminatespotential downtime.When implementingindustrial networks, downtime can bmuch morecostly than with a typical commercial network.If an employee experiences athirty-minute delay in receiving e-mail, it’s merely an inconvenience.If there is a thirty-minute gap in Industrial network, the consequences can be costly, even catastrophic.Redundant power inputs, for example,eliminate outages causedby a bad power supply, power outage, or faulty wiring. When the first powersource becomeunavailable,the device automatically switches over to the second power source.Once power is restored,the device revertsto using the originalsource. Another typeof redundancy is network redundancy.  Managed switches can provide protocols such as the Rapid SpanningTree Protocol or RSTP. However, recovery time of RSTP or STP is not quick enough to critical applications.  In addition to STP and RSTP, LCSI Industrial Managed Switches provide proprietary redundant ring protocol called X-Ring which can recover within 20ms when link fails.
VLANs allowa switch to logically groupdevicesand to isolate traffic between these groups even if all the devices share a common physical switch.For example, if the switchwas being usedfor both office communications and factorycommunications, two VLANscould be created to isolate the office communications from the factory communications. Some switches also allow devices to be located onmultiple VLANs. This issometimescalled overlappingVLANs. If one device, a SCADA system for example, needs to communicatewith both theoffice and thefactory, then this devicewouldexist in both the office VLAN andthe factory VLAN. This would isolate traffic between the remaining office and factory devices, butallow the SCADA system to communicate on both networks.
Traffic Monitoring providesthe ability to view different types of transmission per port to ease troubleshooting of specificdevices having communications issues
The above-mentioned features are justa few samples of common featuresand protocols found in most managed switches.Thereare other features that may be availabledepending upon the particular switch that isbeing used.
Several applications, suchas IP videosurveillance andmany popular Industrial Protocols like Ethernet/IP, as well as many others,use multicast and/or broadcast messaging to increase performance.  Multicastmessagescan be more efficient than Uni-cast messages, but can also increase network traffic.Without IGMP snooping, multicast messages essentially become broadcast messages whichcan decrease network performance, or possibly bringdown the network altogether.  IGMP Snooping helpsreduce bandwidth and increase efficiency.
It’s better to always use managed switches.  Unfortunately, in the real world customerface obstacles such as budgets and price points.  So, there is a trade-off. 
DMC Firewall is developed by Dean Marshall Consultancy Ltd