Don't let information overloadwhelm stop you from reaping the benefits of browser-based applications.
Numerous
compelling finance, functionality, and productivity reasons exist to move 5250
green-screen applications to a GUI Web browser, yet many shops keep
procrastinating. Why? Besides other IT priorities and economic uncertainty, the
biggest reason is the confusion caused by an avalanche of information,
techno-speak, and conflicting claims from a plethora of vendors.
This
doesn't mean you should stay in deer-in-headlights mode and do nothing. You know
you need to move forward, but how best to break the inertia? How about starting
by reading this article? Here, I'll provide a simple, high-level view of this
often perplexing subject. In doing so, I'll help you clarify your business case
for a 5250-to-Web initiative, present a variety of important considerations when
researching any vendor solution, and give you a quick look at the different
types of available vendor solutions.
Reasons for Moving from 5250 to the Web
Some reasons to move applications to the Web are
obvious, while others are not. See how your own needs match up, and don't be
surprised if you discover reasons for getting graphical that you didn't expect.
User Expectations
Many users, especially those who have entered the job
market during the past 10 years, expect an application to have a graphical look
and feel. Although the business logic of a green-screen application may be
cutting edge, it will likely be judged as ancient technology.
For
practical reasons, it is critical to support the users who can relate to
software only while resting their hand on a mouse, and in many organizations,
these folks are becoming the majority. First, training is faster when staff is
using a familiar interface; second, graphics on the screen can enhance
software's ease of use, which may translate into increased user
productivity.
But it's not just daily users whose productivity can
improve because of a GUI. Managers and executives are more prone to dive into
the application when it has a GUI interface, thereby getting to know their
business processes better and extracting decision-critical information in ways
they never expected.
Better Data Presentation
Browser-based screen presentations can consolidate
data from multiple screens (or even multiple applications) onto a single page,
because the data isn't constrained by 20 rows and 80 columns of fixed-size
characters (27x132 if condensed). This, of course, can make information access
more efficient, especially when graphics are added to organize and navigate the
data. For instance, with consolidated information, customer service reps can
view comprehensive information about customers and their orders on a single
screen, eliminating the need to jump between screens.
In addition, in a
business world where financial, manufacturing, and distribution operations are
rarely under one roof and on one system, seamless integration from disparate
systems and locations has become a necessity. With a graphical presentation,
information from a variety of sources is more easily consolidated and presented.
E-Business Opportunities
Whether you're developing a complete online
e-commerce site for customers to create, change, and view orders or you're
designing function-specific portals for vendors, partners, and staff, e-business
is high on the list of why companies need browser-based functions in their
applications. New opportunities and efficiencies can be realized when you
include selected data from your legacy applications in a Web portal.
E-business can provide significant cost-savings by lessening the
frequency of manual intervention when transactions occur. The manual entry of
information from emails, faxes, and phone calls into your applications is always
a point of vulnerability for errors. When information can be input directly into
an application, the potential for error (and the costs associated with errors)
drops dramatically.
With an online presence, not only can transactions
be created and changed online, but a broad geographical presence is made
available for your roving staff. Your salespeople can review orders and solve
problems (or prevent them) while they are on the road, and staff can update data
from remote locations.
Centralized Application Delivery
Rather than install every application on every
machine that uses it, you can deliver and maintain the application from a
central location via a Web application server. The benefits include a single
point of software maintenance, simplified security and data backup, easy
integration of data from multiple locations, and less use of resources on your
remote servers. And if you also sell your applications, delivering them via the
Web on a "subscription" basis can open a whole new pool of potential
customers.
Reduced Interactive Workload
Green-screen 5250 applications require the use of
interactive processing, for which IBM, of course, charges a premium, and it is
likely that this premium will just keep rising. For instance, the newest
entry-level iSeries 810 with the Enterprise Edition option, giving you all of
the interactive processing that you want, costs $44,000 more than the machine
with the Standard Edition, in which you pay extra for any interactive processing
that you want.
Many of the tools that turn 5250 applications into a
browser-based interface move the interactive processing to batch subsystems,
which means that you can either forego adding more interactive CPU on your
existing machine or completely skip it on a new machine. In some cases, this can
more than pay for your 5250-to-Web initiative.
Considerations When Evaluating 5250-to-Web Solutions
Once the business reasons for moving to the Web are
clear to you, it's time to consider your specific needs and to assess your
limitations; these include costs, skill sets, and time constraints. Many
products can help you move from 5250 to Web, and each was built to solve some
particular need, although it may not necessarily be your need. Avoid a
black-and-white approach to these solutions, and don't let vendors push you. As
is the case with most areas of IT, there is no magic bullet.
The first
thing to remember with any kind of IT purchase is that vendor service is a
critical consideration and should carry a good deal of weight when making a
purchasing decision. Before buying, ask for references and speak to customers
who have solved challenges like your own.
Also, when looking for a
solution, make sure it satisfies four critical considerations in light of your
business needs: functionality, user acceptance, system compatibility, and
accommodation of future needs. Let's take a closer look at these.
Functionality
It's critical to evaluate the level of presentation
that you want from the browser before looking at solutions. One application may
only need Web-accessed terminal emulation, while another just needs simple
screens in which function keys are converted to buttons and prompt fields are
transformed into pull-down lists, while a third requires the delivery of a true
"Web" look, feel, and functionality.
You also need to consider whether
your applications need to concurrently support a green-screen presentation. If
so, be sure to understand whether the solution will require you to maintain two
sets of source code.
It is important to know at the outset whether all or
just some of your applications need to be enabled for browser access. Of the
ones that do, does the entire application need a makeover or only portions?
Understanding this can make a big difference in the kind of solution that you
choose. There are tools and even suites of tools that can support a variety of
needs.
Finally, within the realm of functionality, you need to consider
how well the solution interacts with whatever Web application server you intend
to use. If you don't have a Web application server and the solution that you
choose requires one particular server, make sure you are willing to be bound by
this.
User Acceptance
It is critical when selecting a solution that you
consider the skill set of those who are to implement solution. How much will
your IS staff have to learn? If you have only RPG programmers, depending on the
type of solution you need, you may need to consider whether you want to spend
the time and money to have them learn Java or other skills.
Keep in mind
that some available solutions can utilize the existing skill set of your RPG
programmers and will often provide a mechanism to batch modify your source code,
if needed.
If your programmers need to add new skills, it is vital that
the vendor be available to support them during this process. You also need to
consider the general skill set of the end-users of your applications. Perhaps
the bulk of your customer's users are satisfied with your green-screens because
they only have to key data into a few simple fields, or maybe most users simply
scan and verify information. Despite all the reasons to go to GUI, there are
still applications where this still may not be a necessity.
Finally, if
you are buying a solution that also provides tools for new development, consider
how the solution fits into your application development cycle. And don't forget
to consider how the tool will fit into your change management procedures.
System Compatibility
The final straw that often pushes companies to a
browser-based presentation is the necessity of adding expensive interactive
processor capacity. As mentioned previously, moving to a browser-based interface
can fully cost-justify the 5250-to-Web transformation process, because many of
the tools that "reface" them move this processor load to batch processing. This
means that you can put off adding an interactive processor, and if you are
looking to upgrade to one of the newest iSeries machines, you may be able to get
away with buying the Standard Edition rather than the Enterprise Edition, thus
saving thousands of dollars.
Even if you are able to dramatically reduce
or eliminate interactive processing by moving to a browser-based presentation,
you also have to consider whether you have enough CPW to do the job. Different
tools will require different amounts of CPW capacity.
When selecting a
solution, also keep in mind whether the converted application will require a
fairly recent version of OS/400 in order for it to become GUI. If your newly
"Web-ified" application needs to run on other iSeries machines that have an
older release of the operating system, this may present a problem.
Accommodation of Future Needs
Before looking at solutions, think about what you
might need to achieve with the Web delivery of your data in the foreseeable
future. For instance, you may soon need to interface with data from other
applications--even applications that are not your own (e.g., data from partners,
suppliers, governmental agencies, etc.).
Also consider that different
user interfaces (UIs) might be needed down the road. Different UIs have come and
gone over the years, and who knows what the next hot UI will be. You may not
want to buy a solution that locks you into one particular UI, as this could mean
having to purchase a different solution later in order to accommodate a whole
different UI.
It is important to understand that the interchangeability
of UIs can typically be accomplished only if the business logic layer is
separated from the presentation layer in your applications. Some available
solutions can retrofit your code with some amazing universal adapters; however,
the source of your programs will likely need to be modified. Solutions are
available that can batch convert your source to make this modification. Still,
such a retrofit can require a great deal of extra work, and some solutions
require that you support two sets of source code if green-screens are still
required.
General Categories of 5250-to-Web Solutions
Now that you know why you might want to go graphical,
and now that you have a basic understanding of the crucial considerations of
such an initiative, let's look at some of the different types of 5250-to-Web
solutions that are available. For the purposes of comparison, these solutions
can be loosely grouped into four major categories:
- Emulation offers
simple Web access to a 5250 data stream. The characters on a green-screen are
presented in a Web browser, so the look and functionality of the screen is
essentially the same as if it were being accessed through standard terminal
emulation.
- Reface (non-intrusive transformation) turns
green-screen output graphical without the need to change the source code.
Function and Enter keys are typically replaced by buttons, prompts are replaced
by pull-down lists, etc. This option is often chosen when source code is not
available.
- Replace (intrusive transformation) allows the
output portion of the source code to be "replaced" by a high-speed messaging
function that acts as a "universal adapter," letting you have the display output
sent to just about any kind of user interface that you want. Replace solutions
always require some source code modification.
- Rewrite completely recodes existing
applications or creates new applications to natively include the new graphical
presentation layer.
Many existing vendor solutions include one
or more of these categories. Although I've listed below some in each category,
the list is not all-inclusive. To begin finding out about more vendors, see the
MC Press Vendor
Directory.
Warning: When you're evaluating a vendor solution,
you're likely to see a snazzy demo in which some of your display-only-data
screens are rapidly transformed into graphical presentations. Before being too
"wowed," be sure to have the vendor transform a few of your more complex screens
so you can see how these will behave.
Emulation
For those situations where the goal is simply to
eliminate thick-client software, like Client Access, and have all internal users
access applications through a Web browser, an enhanced terminal emulation
product with Web access capabilities can be the answer. The benefits are simpler
workstation configuration and easier access of applications via LAN, WAN, and
VPN. When looking at emulation solutions, make sure they will emulate function
keys.
Products • Mochasoft
5250 • Teamstudio Screensurfer
• CABEL AS
to Web • Seagull
BlueZone • IBM Host
On-Demand • IBM
iSeries Access for Web • ADVANCED BusinessLink
GUIStyle • Jacada Terminal Emulator
Reface (Non-intrusive Transformation)
Reface tools essentially transform each screen in a
legacy application into a graphical presentation by taking the character-based
output specifications of each screen and converting them on the fly into HTML
and/or JSP equivalents. With solutions that fall into this category, there is no
need to modify source code; therefore, developers can manage a single set of
code and let the refacing tool do the rest.
You might think this is the
same as the screen-scraping tools of the 1990s, but reface technology has
evolved a long way from the laborious, tedious, and functionally limiting
process of yesteryear.
Reface tools either work from the DDS or take the
actual 5250 display output. With few exceptions, these tools require an
interactive processor because the 5250 output is still being generated.
With reface tools, developers don't need to have Java or Visual Basic
skills. In fact, modern reface tools typically define the output with an
intuitive design template or style sheet (also called a graphical style
repository) in which you define a set of rules to guide the look and properties
of the screen. Many tools also include a WYSIWYG design function.
The
upside of reface tools is a quick, non-intrusive facelift for your applications
that requires few if any additional skills and doesn't require you to have or
change source code. The downside is that they still require an interactive
processor, they typically require a fairly large footprint on the host, and if
you want to significantly modify the browser-based screen output of the tool
beyond what can be achieved with the design template, you are on your own to
know at least HTML and possibly Java.
Products • BOScom Jadvantage • California Software
BABY/iSeries • IBM Host Access
Transformation Server (HATS) • IBM
WebFacing • Jacada Integrator
• Linoma
aXes • looksoftware newlook
• ResQNet
ResQNet • Seagull JWalk
Replace (Intrusive Transformation)
Replace tools require that the existing legacy
source code is modified to have the output portion of the code (the 5250 data
stream) "replaced" by a high-speed messaging API that acts as a universal
adapter. In other words, the display file I/O requests are replaced with API
calls within your source code. In order to accomplish this, the business logic
is separated from the presentation logic in the code.
Of course, the
downside of replace tools is that you need to modify the output portion of all
of your application's source code, although most replace tools include utilities
to help you automate this. Still, there can be a fair bit of up-front
maintenance required. Additionally, if you also need to support green-screen
users, depending on the tool that you choose, you may find yourself managing two
sets of source code.
The benefits of using this kind of tool, however,
can be significant:
- Eliminate the application's interactive workload by
replacing the 5250 data stream. This is about the only way to achieve this
without a full rewrite. The exception is IBM's WebFacing solution, but only when
running on the newest model iSeries machines.
- Use just about any kind of existing user interface as
well as any other that comes along. This is especially useful if your current or
future requirements include sending application data to various kinds of
information portals.
- Achieve a true Web look and feel, which is often not
available in a reface tool.
- Minimize the hit on system resources when you need to
make data available in an event-driven environment (e.g., the general public via
the Web). Because the code is modular, as each request for data occurs, the
required fields are passed, data is processed, a response is sent to the
requestor, and the job terminates.
Products • Jacada Interface Server • System
Objects JACi400 • Linoma
Envoy • Pluta Brothers Design PSC/400
• Seagull
Transidiom
Rewrite
Rewriting involves recreating existing applications
from scratch or building brand new applications that allow your choice of a
graphical presentation layer to be natively included. Various development
products can also transform legacy source code (e.g., RPG, COBOL, etc.) to
another language (e.g., Java), which helps when migrating apps--although the
automation of source code migration can be a tricky process.
Rewriting
tools are useful not just for developing larger applications, but especially for
smaller browser-based initiatives that include pieces of legacy data. In these
cases, XML, SOAP, and other protocols are often used to port data from a variety
of applications residing on different platforms into the end product. Again,
depending on what you want to do (either now or in the foreseeable future), be
sure that the tool you choose can accommodate your
needs.
Products • ADVANCED Businesslink
Strategi
• BCD ProGen WebSmart
• Computer Associates Advantage 2E
• Freestyle-400
Freestyle-400 • Genexus GeneXus
• Jacada Studio
for iSeries • System Objects Jbuilder for iSeries
• LANSA for the
Web and LANSA Integrator • mrc mrc-Productivity
• Profound Logic RPG Smart
Pages • Relational-Data
RelationalWeb • Seagull
LegaSuite • IBM WebSphere Development
Studio
Go Forth
Now that you've taken in the 30,000-foot view of the
5250-to-Web world, you should be able to constructively explore your business
reasons for this initiative and more closely understand your own constraints.
With this knowledge, you can begin to absorb more of the details on this subject
both from industry resources and by picking the brains of vendors who can be an
extremely valuable resource of information and education on the
subject--especially when you know what questions to ask. As you expand your
understanding, you will be able to more objectively assess vendor solutions and
find the right tool or combination of tools that will be both affordable and
suitable to your needs.
Best of all, you will confidently leave the
crowded ranks of the "5250-to-Web perplexed" and begin to realize all of the
benefits that these technologies have to offer.
Some additional
resources:
Bill Rice is an information technology writer and
marketing consultant. He can be reached by email at
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