Why IBM I on Green Screens Proxy Service?

The most common question we were asked is a question from this post title.

Well, any CEO, CFO and other decision makers already knows that TCO (total cost of ownership) is the most important reason to buy one product instead of another one.

Our product has a very low TCO in both categories (maintenance cost and usage/running cost) which makes our product very attractive. We invested large amount of time and energy to optimize our product for security, network and processing performance making this product top notch. Those optimizations along with large number of features enables huge savings in so many levels that we decided to write a blog post about it.

Here we will write only about segments where our product can dramatically reduce operational and maintenance cost and save a large amount of money to a company. So, let's start...


IBM I has a SCS printing format which is not supported by most printers. One will have to buy special expensive version or custom plug-in modules. Another solution is to buy and install other 3rd party products just for printing to PDF?

Imagine you have 1200 offices and 5000 workstations. You will need 1000 expensive printers which cost about 1 million USD. Just for printers! This is much more than one-time license price for our product for 5k workstations. And yes, printers break. Over the time your expenses will double.

Printing to PDF is electronic, saves paper, it's ecology friendly. Have a support for archiving, scripting, overlays, digital signing etc. If you really need to print you can buy affordable ink-jet for 50-60USD. PDF can be printed on almost any printer including mobile device attached printers through BT or WiFi or USB.

NOTE: We support many in-house developed drivers as PDF, TXT, ZPL, HTML, JSON, JSX(JavaScript server side processing), IMAGE (bmp, png, jpg, tiff).


Our system is highly optimized for network traffic. One round-trip use 720 bytes in average. Many competitors use 20-25kb of data. Some solutions are very chatty and a lot of data travels through a network whenever user types something on the screen. That requires fast and reliable network.

Now, imagine you have 1200 offices and 5000 workstations. Multiply 5000 with 720 bytes compared to 25kb.

It is 3.5MB/sec to 100MB/sec for bandwidth.

In our case, ADSL2+ is enough. In competitor case you will need dedicated optical network. Even if one ADSL line is not enough 2 lines are. They are much more affordable than fiber-optics. Maybe fiber-optics is not available depending where your base is. What then? Will you move main server and operations to a new location?

This can save 20k-30k/ year. In 10 years, it is almost another set of 5k license prices saved. In other words, in 10 years our product will pay off by saving money in reduced network traffic requirements only.


Usually, responsible companies will buy redundant systems when buying a service which should be reliable. In our case, 2 moderate servers are enough to have redundancy. Some competitors need 2-4 servers running to support few thousand connections. We invested a lot of energy for engineering and testing to make system very low for resource demands so our system can handle 2000+ workstations / processor core.

This will save 20% of license price for 5000 workstations in 5 year's time period compared to competitors.


To continue on servers - if you are running our system in cloud environment. Single VM instance 1-GB with 1-Core can handle ~2000 workstations. Such instances cost in average 25 USD monthly with included few gigabytes of traffic. As our requirement for bandwidth and data is very low, chances that you will have to pay for additional transfers are very low. Many competitor products require special servers / environments. Some solutions are available only on IBM I. Will you buy another IBM I just to run some web service on it? NO, probably not. Our system is Java based and can run almost anywhere.

For *150-300USD monthly you can handle 5k workstations with included redundancy and other features provided by cloud operator.

* Price depends on cloud provider, features enabled as SSL, firewall, proxy etc.


Yes, you read it right. Some clients want to move from classic desktop to tablets/chromebooks. As there is no reliable terminal product that works on tablets (Android) they are forced to use desktops only to run 5250 client SW. Today all goes to the web as Office 365, Google Docs and many more. Many special SW as hospital patient records goes online. So why not 5250? We have solution which enables you to switch to Android with support to print spool files on Android device from classic laser printers to Zebra thermal printers.

Now, imagine you have 1200 offices and 5000 workstations. ย Multiply this with 600 USD as an average price for desktop PC and compare it with 100 USD for tablet. Difference is 6x in price reduction. From 3mil. USD cost to 500k. in 5 years of equipment amortization.

This will save ~2.5mil. USD.


We invested 3000 hrs. in testing and developing security and performance segment as we targeted cloud environments also. Beside full SSL support, we added custom additional layer of security which works out of the box (completely invisible to the end user). That additional layer uses modern security encryption schemes similar to PGP including advanced filtering, session access control, OTP verification and many more to isolate and protect your IBM I system from direct online access.

Even IBM I is very reliable and secure system, isolating from Internet is "better to prevent than to be sorry later" without limiting users is one of our key elements.

Companies lose millions of USD because of data breach or breaking-in to the system. Our product is here to prevent huge expenses in a case of breaking-in and stealing enterprise data.

How much money this might save depends of type of business you are doing, but for sure this can be in millions of USD.

User Experience

As some competitors' products create a large amount of data that travels through network, we have seen 1.2 sec / request-response times. In our case average is 135ms which is ~10x faster. And it is very close to native desktop apps which needs about 75ms from response to render screen to be ready for input.

That enables fast and fluid response giving very good user experience.


To continue to user experience.... modernization is an option. Generally, it is not needed but still some clients want graphical GUI. It is very usable in mobile devices as terminal screens are not easy or quite pleasant to use on small screens. Doing conversion and maintaining double code is complicated and expensive.

To make long story short, having simple web templates which improves user experience especially on mobile is a great option, but for fraction of a price compared to other solutions. ย In most cases one does not need to convert all screens, only a few dozen. 100 modernized screens will cost you ~5k USD one-time only and they are easily customized web templates your IT team can maintain without further cost. ย No need for program changes and double code maintenance.


With all mentioned we got to numbers close to 3mil. USD savings in 5 year's time period. Price for 5k licenses is a fraction of that saved money.

So to answer a question from title "Why IBM I on Green Screens Proxy Service?"

Very low TCO with huge savings for a company.

Green Screens Proxy Service will pay for itself over the time of <5 years.

Is it affordable price, quality, features, performance, high level security, web integration, mobile solutions, printing features, UI modernization, central management, cost reduction, cloud support...?

Every prospect has a specific requirements. Except TCO, we canโ€™t give you the answer, but we can help you to find out the answer. You have to choose the best reason. And if we don't have it in our portfolio, tell us about your needs.

We have clients running our SW in production from various industries as metal industry, fashion and stores, retail, electrical industry, car industry, insurance industry etc.

They all recognized our product as affordable and valuable solution.

That only confirms our product can and is easily competing with other products because of product quality, advanced features and affordable pricing we provide.

The simplest answer to a question "Why to buy Green Screens Ltd. products" is ... Just try it and see for yourself.

Send us request for *cloud or local installation for testing our product with your system through our registration form.

Cloud version requires Internet access to your IBM I server.
To get demo license, we need your system serial number.

To find out more please look at our:

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