OPC UA alternatives (aka Kepserver)?

I would like to deploy Ignition on Linux cloud and communicate with 100’s of remote RTUs and PLCs via VPN. Windows based OPC UA servers are NOT suitable for remote management apart from stability and security issues.

  1. Is there any linux based robust alternative for Windows based OPC UA servers like Kepserver?.

  2. Can MQTT be used in place of OPC UA?.

  3. A new protocol called “WOOPSA” claims to be a far better alternative to OPC UA and it can be deployed on Embedded devices, Linux, Node js etc.

Please share your views.

The strength of kepware is the amount of drivers it has. There are lots of open-source OPC-UA libraries. Even the official C# OPC-UA library is open source. But the question is if you can communicate to the other side, over the closed protocol.

Many PLCs support OPC-UA natively, so you don’t even need a translator like Kepware in between. Ignition can connect directly to it.

As a conclusion, you shouldn’t try to find an alternative to OPC-UA, but rather find an alternative for the proprietary protocols still in use.

I love Kepware but for Windows. I wish, Kepware releases a Linux version too asap. Nevertheless, it opens up a great opportunity for others to build something better than Kepware on Linux.

That kills innovation. OPC-UA is not suitable for IOT. Check OPC-UA vs MQTT. Above all, OPC foundation is stuck with Windows and has failed miserably to bring good products on Linux platform. WOOPSA may become a very good alternative for OPC-UA.

That will be very hard, as Kepware is quite low-level and uses a lot of Windows things, like DCOM for OPC-DA support.

OPC-UA isn’t Windows based, it’s completely unrelated to the older OPC-DA, and uses none of the annoying DCOM things from Windows. Instead, it just requires plain tcp/udp and custom encryption. OPC-UA is an open protocol btw, the OPC-foundation isn’t the only one releasing products. There are OPC clients and servers for many other programming environments.

MQTT on the other hand isn’t comparable to OPC-UA. OPC defines the structure of your communication, like you would have REST web-services. While MQTT is just like HTTP, it gives some way to send messages with acknowledgements, but that’s about it.

WOOPSA indeed tries to be an alternative to OPC, but as it’s based on JSON over HTTP, I doubt it will be native to PLCs anytime soon. This protocol will be a lot heavier than OPC, and thus even less suited for IOT.

Wow! I can’t let that one go.

WOOPSA heavier than OPC UA? By what measure?

The specification for OPC UA currently runs to 1,044 pages, excluding the new section on Publish/Subscribe. The specification for Woopsa is less than 11 pages.

Implementing code to parse OPC UA properly would take many months of work. I doubt WOOPSA would take a day. It seems ideally suited to low-powered edge-of-network devices.

OPC UA is for big company data acquisition. You’ve got to love the detail they’ve gone to, but most people will never read the specification let alone understand it. The only reason we can use it is because companies like IA and Kepware have done the heavy lifting. Protocols like MQTT and WOOPSA are at least human-scale and understandable. They won’t solve every problem but problems that are too big for them are probably too big for me :slight_smile:


By the only measures that should matter in the end :slight_smile:

Can this be reasonably implemented on an embedded processor? How much CPU time does message serialization take? How much overhead on the wire is there?

I suppose they all have their place though.


One company which knows OPC-UA on Linux very well is IA.

Ignition will offer the industry’s first fully cross-platform commercial OPC-UA server absolutely free. Ignition OPC-UA offers a variety of drivers - with many more to come - and an open driver API, all at no cost to end users.

What happened to this promise?. It’s time for Ignition to make their OPC-UA open source and 100% free community version (with all drivers). Ignition can always charge for the pro-version. This decision will push Ignition adoption rate exponentially. We must keep in mind that every serious business will go for the paid version eventually. IA has the most powerful marketing weapon (free OPC-UA) to capture the market. I need NOT teach these simple tricks to IA. With all due respect, i would like to mention that IA has failed miserably to market Ignition, outside US territory.

Ignition must also look into affordable cheaper licensing models like 5000 tags, 10,000 tags and 65,000 tags for small and medium class projects which is a big market share.

We need a David to kick the Goliaths hard :wink:


List of Open Source OPC UA Implementations:

Kepserver alternatives are coming. Kepware must launch open source free community version on Linux asap. Otherwise, they will loose their market share drastically within a couple of years like Nokia was sleeping until Android kicked it out. IA too must take note of this point and do the needful asap.

This is where I completely disagree.
We do NOT want a tiered tag licensing model. Ignition is already way ahead price wise and their model is storming the industry and causing massive waves.


This is NOT cheap but very smartly priced. This is typical pricing of most of the SCADAs. Around 40% of projects are less than 3000 tags and 90% are below 65,000 tags. Ignition pricing is very attractive for 100,000+ tags projects but unaffordable for 2000 tags project. Even though Ignition is very powerful, SI’s, outside US (in developing countries), won’t be able to win many projects with a starting price of USD 15,000/-.

I would appreciate, if anybody could give a price comparison of different SCADAs vs Ignition based upon number of tags.

Go price out Wonderware or FactoryTalk or WinCC and you will see what the word expensive means when it comes to SCADA.

Just to get a Historian going on any of those packages will cost you more than the full suite from Inductive.
Nevermind the fact that they charge thousands for EACH client.

I don’t think you will get anyone to quote actual pricing here as most are based on volume.

But I can tell you that Ignition is vastly less expensive, and a better product too!


How-To Get Started with Mosquitto MQTT Broker on a Raspberry Pi and ubuntu

It works perfectly on Ubuntu also.

—Shell Commands—
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install mosquitto
sudo apt-get install mosquitto-clients

sudo nano /etc/mosquitto/mosquitto.conf
allow_anonymous false
password_file /etc/mosquitto/pwfile
listener 1883

sudo mosquitto_passwd -c /etc/mosquitto/pwfile username
mosquitto_sub -d -u username -P password -t “dev/test”
mosquitto_pub -d -u username -P password -t “dev/test” -m “Hello world”

Excellent tutorial to understand MQTT::

1 Like

How to quickly test MQTT with Ignition?:

Note: To learn and setup MQTT on ubuntu or RPi, please watch the above 2 MQTT tutorials. Thanks.

  1. Install cirruslink MQTT Engine module and activate it.
  2. Click the MQTT Engine/settings link on the Ignition web configuration page and add any numer of MQTT servers as shown below. In this case, i have added 2 servers, local ubuntu and cloudmqtt servers. Make sure, you enter your cloudmqtt port number, user name and password as shown in details tab.

3.Click namespace/custom and enter everything for name and # to subscribe for all servers as shown below.


5.Enter the Ubuntu shell command:
mosquitto_pub -h -p 1883 -t test -m “hello ignition”

6.login to your cloudmqtt page and test it.

All topics will automatically come up under “All Providers/MQTT Engine” in your tag browser.

I am amazed and speechless to see the power of MQTT. This will push Kepserver out of business very soon.

Do this for a 15,000 tags license with any SCADA. Ignition will be the first looser. A huge number of projects are less than 15,000 tags. SI’s can NOT do business for a loss, howsoever powerful a product may be.

Multiplatform mySCADA is becoming a favourite among SI’s in ME and India for small and medium scale projects because of their smart affordable pricing. I wonder, while IA can release a 500 tags limited edition for Ignition Edge, why can’t they do a tiered tag licensing model for Ignition SCADA also?. mySCADA pricing model is the best one for Ignition to follow.

India is the biggest middle class consumer market in the world. The market of ME is controlled by Indians. Whatever sells in India, it will sell in China and the Indian subcontinent will follow. Learn form Microsoft and Google.

Change is inevitable. IA must also change before it’s too late.

Don’t try to sell me a 80 wheeler truck, when i just need a car:

Perhaps contacting your IA sales rep would be in order. There’s more to life than what’s on the web page.

This is mine comparations with Siemens WinCC and Ignition from last year for one customer, where I wanted to replace WinCC SCADA with Ignition.
Ponudba za dodatni WinCC client RT 2017.zip (24.0 KB)
Last week we get the job. :slight_smile:


Good one. We need more such experiences. If so, why other SI’s in developing countries could NOT sell Ignition?. I would like to repeat again that Ignition is the most powerful SCADA in the world.

I suggest, IA must conduct an opinion poll with all the registered SI’s and users to know why they could not sell Ignition in their region or country?.

FactoryTalk Tranaction Manager. No 15K-tag option. Jumps from 5K tags to 32K tags. The price also jumps from $16,400 to $24,000.

Just the transaction manager.

Back in 2008, A WW quote with 50K tags, 1 development license and 5 clients was close to $120,000. I have no idea what that would be in today’s terms, because I never looked back.

I submit that SI’s have a difficult time moving the product for two reasons:

  • They have a difficult time explaining why Ignition is the better choice in a long-term vs short-term benefits view.
  • Customers tend to look only at what is cheap, instead of what is good.

There’s a bunch more I could say to this leading to pursuit of excellence, but work beckons…


Why presume?. Why can’t IA ask the SI’s instead?. Let them share their experience and tell what difficulty do they have in convincing good clients.

IMO, an SI is NOT a sales agent for IA. He has to procure items as per his budget and BOQ. He is the front end customer for IA. He needs to be convinced first, so that he can convince his clients down the line. Who will do this job in that region or country?. Does IA engage any one to engage SI’s like SIEMENS, Rockwell and Schneider?.

SCADA is NOT a 29 dollar anti-virus software which any one can download, try and discard if he doesn’t like it. It’s NOT easy for people in certain countries to get US visa apart from expensive travel costs. SCADA is a serious business, bread and butter of an SI. IA must look deeper into their business model and find better ways to win the confidence of SI’s and make them feel closer to IA.