Slenderizing Network Infrastructures

Deploying thin clients in an AS/400 environment--It's a mix and match game where even old PCs can play a part

Are PC users and application installs taxing your IT staff to the limit? Would you like to have more control over who has access to particular data and software? Does your organization need e-mail, e-scheduling, and/or e-commerce capability for green-screen users across the enterprise? Or perhaps you'd like to start using your AS/400 for Windows applications?

If you answered yes to any of these questions, you may already be thinking about, planning for, or preparing to deploy a thin-client solution. If you're comfortable with your current AS/400 environment, and yet recognize that your company's needs or direction could change at anytime, you need to know that today's thin-client technologies are more than just yesterday's network computers. Moreover, in certain thin-client environments, your old PCs can be "upgraded" to serve as thin-client terminals, which can offer some significant cost savings.

No matter what reasons you have for exploring thin client as a solution, there are a number of challenges that you need to prepare for before you select a specific set of technologies, network options, and application upgrades.

Technology Challenges
Generally speaking, there are currently two ways to implement a thin-client solution in an AS/400 environment. The traditional approach is to use the AS/400 as the central server with thin clients connected directly. The other scenario adds a second tier to the process. Here, the AS/400 uses an Integrated Netfinity Server (or other NT Server) to provide end users with access to Windows applications via Windows NT 4.0, Terminal Server Edition (TSE). Terminal Server provides a core operating system, management tools for both server and client sessions, and a display protocol for communication between the server and the TSE client software.

At this point many solution providers recommend adding Citrix's MetaFrame software to support a broader range of client hardware, operating platforms, network connections and LAN protocols.

"If I log onto a server directly with a data-hungry application, I may be a load hog on the system," says Mike Richtberg, senior market development manager at Citrix. "MetaFrame with ICA (Independent Computing Architecture) provides an architecture solution that encompasses every aspect of your system--from applications and terminals and PCs on the desktop to your entire network." Management utilities, resource allocation guides, and installation tools are used to load balance the applications.

"With MetaFrame and ICA all applications can be published from a centralized, thin-client location," he adds. This means, he explains, that instead of logging onto a local server, a user can access a published application by name, or view an on-screen display of a group of icons that represent published applications they can point and click on for access. "To the end user, it looks like any other Windows application that would be running locally--only with MetaFrame, ICA evaluates all the user farm characteristics to distribute usage across the most efficient server."

Beyond MetaFrame, there are other options available.

As Howie Hunger, director of channels and marketing, network stations for IBM explains, "Our focus is on a broad range of applications and solutions used by customers. Much of the thin-client market has focused on the Windows server. We've taken a broader approach. We believe that being able to run emulators and browsers is critical as well.

"When you're going from an AS/400 to a thin client, with OS/400 on an IBM Network Station you can run your management software on the AS/400 at the server level via 5250 emulation. Your browsers can be attached to Web-based applications, Java applications, Windows applications, or any other applications that run on a server with access to the AS/400," explains Hunger.

"You can look at host access and connectivity in two ways," says Stephen Drake, senior research analyst at IDC (Framingham, Mass.). "The traditional direct approach, or from the Web to a host where clients have access to the AS/400 through a browser. Our research is showing that the direct access approach is shrinking compared to the browser." But Drake also points out that host access vendors have spent a lot of time marketing traditional host access products as integrated solutions.

Perle Systems (Westmont, Ill.) allows AS/400 shops to enhance the performance of an AS/400 thin-client host via an internal network controller, the Perle 594e. "Our customers see a remote network server with twinax running on the SNA architecture as the most efficient way to operate their business. They see no need to move to a graphical user interface (GUI), which could dramatically confuse their end users and increase support costs," says Sean O'Donovan VP worldwide marketing, Perle Systems. "SNA applications and operating systems are tuned to the current business operation, and customers don't want to change because devices aren't replaceable at this time. However, for customers who need to move to GUI desktops, our controller lets them maintain SNA and their current twinax equipment, while also allowing them to deploy IP (Internet Protocol) desktops on the twinax line."

On the other hand, Stephen Malkinson, manager, Network Computer Division at IBM, notes that, "Having ICA access is critical to our success. We focus exclusively on Citrix. Our customers are transitioning from a host-centric environment to one with a PC look and feel. With MetaFrame, we can offer customers the ability to run their server off an AS/400, while also providing the windows and GUI environments for applications like ERP from JD Edwards."

Current technology, number of users, and types of applications you run will have a direct impact on the solution you choose. "It's true that your mileage may vary," says Malkinson. For example, he cites how different applications have a direct impact on a server's ability to maintain horsepower. "You may be able to have 500 users accessing JD Edwards software off a single server, but only 300 SAP users."

Other technology issues that may impact the solution you choose include:
  • session shadowing and local device support;
  • problems associated with an aging installed base;
  • the fact that network stations require current software releases;
  • and the TCP/IP skills of your staff.
"For a guy with SNA and twinax who's been through three upgrades, switching to a MetaFrame solution really requires a paradigm shift," says Malkinson.

Thin Client Benefits
"The key attributes that customers look for in thin-client implementations are rapid application deployment, centralized management with access to any server, and a lower total cost of ownership," says IBM's Hunger.

Malkinson agrees, "Compared to loading software on individual PCs and servers--which can literally take months--thin client is a centralized, one-time load per application or upgrade."

Other benefits include increased security and control, the virtual end of helpdesk support for applications running on thin clients, tracking of peer-to-peer help, and in most cases, reduced licensing costs. "When you do the math, [software licenses] cost up to 35 percent less," he says.

Thin Client Trade-Offs
From the end users' perspective, however, thin clients may be a blessing or a curse. "If you're running green screens, moving to a thin-client environment isn't a big deal. But if your people are using software that can't be supported by thin client, or hasn't been supported by thin client, like applications that are running on PCs, then the problems get significantly more complicated," explains Chris Gloede, executive VP, Business Solutions Group (Arlington, Va.).

Peter Lowber, research director, Gartner Group (Stamford, Conn.) agrees, "Thin client lets you access a heterogeneous environment. The AS/400 environment has typically been built around inventory control, task-oriented applications, and transactions. These operations are amenable to thin-client operations." However, when you add Windows terminal servers, 5250 emulation, and make Windows applications available, "AS/400 users can use their windows terminals to access e-mail, Outlook, the Internet, etc., and they can be much more productive," he adds.

Lowber stresses that IT managers should not think of thin client as an all or nothing proposition. "Think of the PC environment as a hybrid. Some systems may serve as fat clients, others as thin. What you may need to do is determine which applications can run as a thin client and which can't."

"For every person who designs an airplane wing on a workstation, there may be 200 other people who need to look at the design. Many of them could be on a thin client to do that," says Hunger. "Call center personnel, purchasing, and people who are not directly involved with the actual design are all candidates for thin client."

Lowber echoes that most users working on a network could easily switch to a thin client. "On the extremes you have those users who have two or three tasks and who may have never used a PC. At the other end you have engineers and designers on a CAD workstation. But most users are in the middle. They're professional or management types with PCs who work on documents all day. Usually, the only problem they face is that thin clients can't work offline. Therefore, for those situations, or if they're on the road a lot, they'd need a laptop. But even a laptop could have thin and fat applications where the users go online for thin-client-based tasks."

In short, says Lowber, "Devices are less important than the software environment and managing applications."

So, how do you move your organization to accept thin client?

"You have to involve users in decision making and the selection process," says Gloede. "Let your users know where you need to go and the reasons why. If users balk, they won't use the system and your investment may end up going down the drain. But if users are behind what you're doing, they'll inherently want to see the project succeed."

Once you have buy-in at all levels, it's time to prepare for rollout, says James Gruener, managing director of Windows 2000 platforms, Aberdeen Group. "Your AS/400 is the heart of your infrastructure. Leverage your existing resources by preserving the investment in your larger boxes. At the same time, cost effective centralization of management for applications and the desktop environment will cut some costs."

He continues by emphasizing that, "This is a definite case where best practices need to be applied. First, you need to determine which applications will be on NT servers, and which will reside on the AS/400. In the pre-production stage you need to make sure that network demands are being met. Testing this is key. Only after testing the infrastructure and executing a live test are you ready for stage three--deployment.

"It's especially important to make it a positive experience for the user base," Gruener notes. "Your customers need to understand how [thin client] helps them decrease their time and liability on the desktop."

Thin client represents a change in thinking for a lot of people. Your people need to remember it's about server-based computing. On the client side this is less of an issue. The biggest hurdle there is to help your customers understand that thin clients let you provide better support for many applications. Says Gruener, "In some ways it's a complementary architecture for the AS/400. It leverages the 400 as a solid enterprise server by giving clients new ways to access applications. Which, in turn, gives clients the opportunity to develop new ways of thinking."

Thin's Future Looks Fat
What's in store for the future of thin client? Citrix's Richtberg says, "Our leading sales indicators and our analysts' forecasts for thin client tell us to expect an increase in use. And we expect that increase to move at a faster and faster rate. Currently, 98 percent of the Fortune 100 and 80 percent of the Fortune 500 are using this technology."

"Microsoft just announced the Windows-based terminal professional which takes advantage of embedded NT 4.0," says Gartner Group's Lowber, "This means that next year, thin clients will be able to provide a full implementation of Internet Explorer 5--Microsoft's version of an Internet terminal--and they'll support both ICA and [Microsoft's Remote Display Protocol] Internet applications. By 2004, over 70 percent of thin-client applications will be browser-based. And, eventually browser-based applications will represent 90 percent of all applications."

IBM's Malkinson sums it up best. "No doubt within six years, thin client will be like a public telephone. You'll be able to go anywhere in the world and use a calling card to connect to your system."