As an Amazon Associate I earn from qualifying purchases from

Why Producers duplicate IPv4 addresses and the way IE switches assist resolve the problems

If this subject piqued your curiosity, you’re in all probability impacted by or no less than interested by duplicate IP Addresses in your industrial community. You aren’t alone. It may be somewhat bewildering. There doesn’t appear to be any purpose this present day to have duplicate IP Addresses, not to mention do it on objective. Let’s unravel the thriller.

Corporations that construct refined machines have made the transition to Web Protocol because the communication protocol inside their machines. IPv4 is the simplest protocol to make use of. There are many software program libraries within the ether based mostly on IPv4. These firms’ core competency is {the electrical} and mechanical side of their machines, not the software program that runs the machine and subsequently they don’t have refined software program groups. Whenever you’re writing communication software program and software program is just not your core competency, what’s the best and least problematic strategy to establish the elements inside your machine? Reply: Static IP Addresses. The choice to static IP Addresses is a extra difficult course of involving dynamic IP Handle project, together with a fancy process of figuring out which IP Handle the person elements obtained.

The IP Addresses have been duplicated on objective. The software program within the machine makes use of static IP Addresses to establish particular person machine elements as a result of it’s simpler for the machine builders. Every machine they construct has the identical software program (SW). Due to this fact, they use the identical static IP Addresses. You probably have bought two or extra of their machines, then you’ve got duplicate IP Addresses. To be honest, it will be a lot tougher and price prohibitive to offer every element of every machine a novel IP Handle.

Determine 1: Robots characterize a number of machines with similar elements and software program

The robots within the image above are an instance of a complicated machine. Every robotic has the identical elements and the identical software program. Every element has its personal statically assigned IP Handle. This observe is just not restricted to robots. Bottling machines and diaper making machines are manufactured in the identical approach.

Why is that this an issue?

So long as you’ll be able to comprise the broadcasts of IPv4 Addresses of the elements to remain throughout the machine, try to be OK. There’s at all times one publicly distinctive IPv4 deal with on the machine which represents the whole machine to the skin world. Once more, so long as you solely use this one IPv4 deal with to speak with the machine, it shouldn’t current any issues. More often than not that is the way it’s completed and everyone seems to be completely happy.

Alongside comes the necessity to enhance productiveness. To extend productiveness, you want extra knowledge. And the place is that this knowledge? One place is contained in the machine. Now you want to talk with the elements contained in the machine. After getting a couple of machine, how do you have to talk with the interior elements which have the identical IPv4 deal with? That is the issue.


Earlier than describing options, I’d wish to uplevel the dialogue to speak about Community Handle Translation (NAT) typically.

All people ought to learn about NAT. We use NAT day-after-day whether or not we all know it or not. The IPv4 router in our properties makes use of NAT. The IP Handle assigned to your private home units (together with your laptop computer and smartphone) is a non-public IP Handle. This personal IP Handle is just not routable on the Web. Our neighbors all have in residence units with the identical IPv4 addresses. It’s not an issue as a result of our residence routers use Community Handle Translation (NAT) to transform personal IP Addresses to a publicly routable IP Handle so we are able to talk with units on the Web. The Web service suppliers use personal IP Addresses for in residence use as a result of it’s simpler for them. There are usually not sufficient IPv4 addresses on this planet for each IP succesful machine to have a novel IPv4 deal with. And let’s face it, we now have not transformed to IPv6.

Your house is just not the one place NAT is used. Industrial networks additionally want to make use of NAT as a result of refined machines have the identical IPv4 addresses.

There are actually solely two methods to resolve duplicate addressing issues for industrial networks. The obvious approach is to insert an extra Layer 3 machine equivalent to a firewall or router between the machine and the remainder of the community—simply to translate Non-public IP Addresses. That is just like what you’ve got at residence. This answer requires a particular community machine for the aim to transform personal IPv4 addresses to publicly distinctive IPv4 addresses. The disadvantage is, that it’s an extra machine to buy and handle and, configuration and administration of this Layer 3 community machine may be complicated, requiring somebody with IT expertise to setup and keep them.

The much less apparent approach is to make use of a Cisco Industrial Ethernet (IE) change to do the IPv4 translation. When the IE change solves the duplicate IP addressing downside, it’s utilizing Layer 2 NAT. Plus, in my biased opinion, configuring Layer 2 NAT on a Cisco IE change is simpler than configuring NAT on router or firewall. There’s in all probability an Industrial Ethernet change in your community already connecting all of the machines collectively. Why introduce an extra community machine? Preserve the identical easy community structure you’ve got with a Cisco IE change and resolve your duplicate IPv4 addressing points, too.

Determine 2: IE-4010 connecting a number of complicated machines

In determine 2 above, every robotic has the identical IP Addresses for its inside elements. The Cisco IE change will translate the duplicated personal IP addresses of the elements of every robotic (ie: complicated machine) into publicly distinctive IP Addresses because it receives the Ethernet frames from the robots.

Pattern IOS CLI configuration for the Cisco Industrial Ethernet

That is how you’ll configure a Cisco Industrial Ethernet change to offer L2NAT for the primary two robots on the left in Determine 2. The remaining three robots could be similar to the primary two.

You begin by defining which IPv4 Addresses to translate. The Cisco IE doesn’t know which publicly or personal IP addresses you need to use. It’s important to inform it. You outline the whole translation.

Outline a translation occasion for every robotic. The ‘leftmost’ robotic would have this translation occasion for 3 of its inside elements. The ‘nextleftmost’ robotic would have the identical personal IP Addresses however distinctive public IP addresses.

Word: The IP Addresses for the within hosts are the identical in every of the 2 translation situations, and the translated public IP Addresses are distinctive. They need to be distinctive if they’re for use within the upstream community to uniquely establish the robotic elements.

The subsequent step within the configuration course of is to use the interpretation situations to the right interface. The ‘leftmost’ robotic is related to port Gi1/2, and the robotic subsequent to it’s related to Gi1/4.

Disclaimer: This configuration, whereas legitimate, is simply an instance.

In terms of configuring something within the IOS CLI, the instance above exhibits how easy it may be. For these of you who don’t like utilizing the IOS CLI, the identical configuration may be completed utilizing the IE’sweb based mostly GUI.


For these of you in search of an answer to the duplicate IP Addressing downside, utilizing the IE change you have already got in place simply is sensible. For these you with out an IE Change, now you’ve got an excuse to deploy one within the entry layer. Particularly in case you have unmanaged switches within the entry layer immediately. Utilizing an IE change is a one field answer. The IE switches do the IPv4 deal with translation at line charge. In addition they translate the IPv4 addresses within the payload for ICMP and ARP.

L2 NAT is simply one of many many options on Cisco’s IE switching options that resolve buyer points with high quality and reliability.

Get extra data on Layer 2 NAT

Study extra about IE Switching

to maintain up with the newest Web of Issues developments and insights that can assist you succeed along with your IoT deployments.



We will be happy to hear your thoughts

Leave a reply

Enable registration in settings - general
Compare items
  • Total (0)
Shopping cart