A Changing of the Client and Networking Guard

The AS/400 has come a long way from the day IBM called upon it to pick up the torch passed from the System/3X family. Back then, the AS/400 was a host-centric, multi-user business computer designed to advance the notion of IS further than had previously been achieved in the small-to-medium business market.

Aside from the AS/400’s transformation from a host-centric to an application-centric server, perhaps the greatest change has come in the AS/400’s role within the enterprise. The AS/400 has slowly become just another component within the network, a testament to IBM’s ideals of integration and interoperability.

In 1988, the world was supposed to be Token-Ring, OS/2, SNA and the MicroChannel PC, according to the recollection of one AS/400 solutions developer. "In truth, it’s turned out instead to be Ethernet, Windows, TCP/IP and PCI/ISA technology," he says. A fairly accurate observation with one exception: it’s everything in between as well. Which is one of the keys to the AS/400’s long-running success. As an open system, the AS/400 accommodates the old and the new, whether it’s SNA or TCP/IP, Token-Ring or Ethernet, fat client or thin client, green screen or GUI, as well as Java, the Internet, remote access and the Integrated PC Server (IPCS).

Twinax to TCP/IP (and all stops along the way)

The landscape into which the AS/400 was born consisted primarily of non-programmable terminals connected to a server via Twinax cabling. Connectivity was via SNA LU6.2 – mostly running over Twinax – from server to terminal, PC or a PS/2-compatible device. While early AS/400 technology offered some PC support, the majority of users accessed applications and data via a green-screen interface.

"LAN protocols were there also, but the market supported primarily 5250 terminal applications," remembers George Weaver, a consultant with IBM’s Partners in Development program and a 16-year veteran of IBM. "Now, many applications require an intelligent desktop device, and the application environment has changed quite a bit. The AS/400 has changed with it, because it’s foremost an application-driven machine."

Early on, IBM established that the AS/400’s mission would be to support all popular protocols and networking hardware, Weaver explains. While the AS/400 has traditionally been an SNA box supported by Twinax, "TCP/IP is where the action is now," he says. "From a communications standpoint, security and reliability are important. Up until a couple of years ago, TCP/IP didn’t offer either, but the Internet changed this."

One of the more prominent transitions in the history of the AS/400 has been from SNA to TCP/IP. "The AS/400 did the best LU6.2 peer SNA support in the industry," says Dick Kiscaden, senior technical staff member for AS/400 strategy and manager of the team that rolled out the AS/400 in 1988. "We’d really made that easy to manage with self-starting controls and so on. We had not done much on TCP/IP. And then when TCP/IP became all the rage, we made investments in each of the last several [OS/400] releases to the point we’re just about caught up with speed and ease of configuration and management of an IP network, as compared with an SNA network."

Initially, performance over TCP/IP "was not particularly good," primarily because the protocol was essentially a port from a "high-level language implementation," he recalls. "We just were not getting any demand for it so we didn’t make much investment in it." This changed eventually and, in 1995, Kiscaden began to work on IBM’s network computing solutions strategy. "The first time we started to see substantial changes in IP capabilities was in 1996," he says. "We’ve made substantial improvements in each release since 1996." As applications become more distributed, users will continue to count on the use of the IP protocol to turn their AS/400s into Web servers.

Another major trend in AS/400 network computing over the past decade has been the move from multi-drop SNA to frame relay, according to Jay Pultz, a research director with Gartner Group (Stamford, Conn.). "Use of SNA by itself does not justify a switch to frame relay, but when Internet access and other IP traffic is added, the move is a good way to combine LAN traffic and SNA on a WAN," he says. Network consolidation drives down costs by as much as 50 percent, as opposed to running separate SNA and IP networks. One problem for smaller networks is that frame relay does not scale down very well, Pultz adds.

The emergence of TCP/IP also affects the composition of the solutions offered to the AS/400 market. One company in particular plans to continue improving its TCP/IP offerings to keep pace with market demand. "People can’t say TCP/IP fast enough," says Jerry Draper, president of Synapse Network Associates (San Anselmo, Calif.). "That’s what the market is demanding right now."

Draper points out that IBM has brought its own TCP/IP offerings along slowly. "IBM has also come a long way in the area of device naming when the user attaches via TCP/IP," he says, adding that with OS/400 Version 2, IBM introduced TCP/IP as "an add-on product sold separately." Versions 3 and 4 first bundled, then improved upon, TCP/IP within the OS.

Though the market will see more and more new products and services optimized for TCP/IP, "SNA will continue to be used and supported for many years to come," adds Chuck Cruz, director of product management for NetManage Inc. (Cupertino, Calif.). "The environment that users are going to be living with is going to be a mixed one for a while. There aren’t enough programmers to re-write everything that fast."

Token-Ring has always been a crucial aspect of AS/400 connectivity, since the midrange server was designed from the outset to serve mission-critical areas of large businesses, according to Jeff King, product marketing manager for Madge Networks UK. The key to Token-Ring’s success in AS/400 environments – aside from being an IBM technology – is its capacity to provide scalability at an affordable price. And after years of investing in Token-Ring, it is expensive for users the change connectivity technology, regardless of the headway Ethernet has made in recent years.

One improvement for hardcore Token-Ring fans has come with the High-Speed Token-Ring Alliance (HSTRA) and its strides toward 100 Mbps – and eventually 1 Gbps – connectivity. For those focusing on the current situation, Token-Ring is "in good shape" for handling newer applications on the horizon, such as voice and video data, according to King.

King discourages the notion that Ethernet is less expensive than Token-Ring, particularly in situations where companies are considering conversion. Ethernet backbones do not offer speed increases over Token-Ring, King says, adding that the move from Token-Ring to HSTR is a "fraction of the cost of moving to Ethernet."

Ethernet has a much larger share of the network connectivity market, but since the AS/400 and Token-Ring both belong to IBM, they are a natural fit, according to Pultz. Despite King’s comparison of costs, Pultz claims Ethernet is less expensive than Token-Ring but also points out there is no compelling reason to "rip out" existing Token-Ring. "100-bit Ethernet is the direction a lot of companies are going with their LANs, and there is a lot more vendor product out there to support Ethernet," Pultz adds.

Another important facet of AS/400 networking and connectivity is Asynchronous Transfer Mode (ATM), a transfer mode in which the information is organized into cells. ATM enables companies to achieve higher speeds than Token-Ring or Ethernet alone and provides a higher quality of service, particularly for online transaction processing. Just as with all networking protocols, there is a give and take. While ATM is highly scalable upward, it is very expensive to scale down to the desktop, Pultz explains. "For this reason ATM is limited primarily to backbone LANs, while frame relay is used for smaller sites," he says.

Client/Server and Thin Client

During the past decade, the AS/400 community has seen the client/server computing model peak, crest, then begin to climb back into favor with the user base, thanks to the growing popularity of thin client desktops.

"When we first came out, 5250 displays and menus were entirely adequate," Kiscaden says. "You used Twinax, and you didn’t really have PCs playing a major part in the business. Client/server came along and that really required an accommodation to a level of networking where some of the application was on the desktop, and we put a lot of investments into technologies like Client Access and even more recently the Toolbox for Java."

Where Client Access provided a set of procedural APIs for getting at the system interfaces like data queues, ODBC and mail interfaces like Messaging API (MAPI), Toolbox for Java provides the object-oriented class library access to those same things, according to Kiscaden. "Client/server drove us to really look at how the application elements – the user interface, the data and the application – were all split up," he says. "With network computing, we’re now looking at server services being distributed, where you have different applications and different servers. We really can expect this trend to continue, and that’s why we see the attributes of Java to be so important. We have just begun to have fully distributed applications."

Over the past couple of years in the connectivity market, one AS/400 vendor has seen a trend where senior general management begins to look at IT technology differently than they have in the past. "In the last four or five years, IT has really be viewed as a cost center," says John Wall, CEO of Wall Data (Kirkland, Wash.). "The whole client/server phenomenon came about in saving cost in host computers, I would argue."

The industry has come full circle with thin client, thanks largely to client/server’s low cost and high security, observes Jim Robillard, VP of marketing for NLynx Systems Inc. (Austin, Texas). Client/server lost some of its popularity because the PC was "liberating when it first came out," he adds.

PCs were not as tightly controlled as centralized resources and introduced an "explosion of new applications – like desktop publishing and spreadsheets – to the marketplace," Robillard says. "But there are still lots of situations where a tightly-controlled client/server environment is still important. Everyone thought client/server would go the way of the dinosaur, and the PC with distributed computing and networks would take over."

Kiscaden points out that the term "thin client" covers PC, network computer (NC) and Windows-based terminal (WBT) applications. In the NC space, IBM’s Network Station is one of the last devices still standing, and Kiscaden believes it has hardly even touched its potential. "When the Network Stations first came out, they were limited to green screens and HTML," he says. "The Network Station as a device for a traditional enterprise application is only just now starting to see the applications come out that in fact can use it. Only recently have Network Stations themselves been fast enough to run Java. It’s Java that allows you to have a thin client like a Network Station, where you can build transaction-processing-type applications."

The client/server era, from an applications point of view, was basically fat client and thin server. The network-computing model is still client/server, but it happens to be fat server, thin client. "That’s one of the really exciting things to us about Java," Kiscaden says. "You can now send down to the client what amounts to a presentation manager, and then run the application on the server and shoot the information back to the client to be presented. You can also do this with HTML, using CGI-type programs. Java actually works out better than trying to use HTML with an application interface."

Robillard sees IBM and the AS/400 taking advantage of new methods of internetworking, specifically IP and Ethernet, as well as Token-Ring to some extent. "IBM is applying the cost-effective networking technology that came out of the non-proprietary computer industry to its own architecture," he says. "So now you have the combination of a really robust and strong server over IP and Ethernet."

For thin-client users and vendors to find satisfaction, both need to be patient. "In another year or two people will start to see the Network Station really does have some good stuff, especially in front-end areas of business where companies have to roll out tens of thousands of desktops," Kiscaden says.

Kiscaden also believes Network Stations are just "wave one" of what IBM refers to as "Tier 0," a set of information appliances that do just one thing. While Kiscaden claims the continued development of Tier 0 devices will expand the whole thin client market, he acknowledges the difficulty in predicting market trends. "Certainly back in 1988, I can’t say I foresaw the whole client/server model. The trick is seeing it before the next guy. I continue to be surprised, which makes the whole thing kind of fun," he says.

Green Screen to GUI (and beyond)

A large percentage of AS/400 users still log on to green screens due to the large amount of code written in RPG and COBOL for the green-screen interface. "At the same time, as people do modernize their applications, we’ve certainly been working with various business partners all through the client/server era -- and more recently in the network computing era -- to develop graphic user interfaces," Kiscaden points out.

At the other end of the screen interface spectrum, IBM launched headlong into its "Point and Click" desktop strategy with V4R3 earlier this month. Operations Navigator, newly enhanced with the release of V4R3, is a big part of Point and Click. While Operations Navigator is not new to the AS/400, PC operating system technology has now matured to a point where Operations Navigator can progress as well, according to Joe DiCecco, senior software engineer and leader of IBM’s Operations Navigator for GUI design.

Windows 95 and newer have 32-bit technology, something not available to early Point and Click. Take the case of Graphical Operations, introduced along with V3R1 in 1994 and a precursor to today’s Operations Navigator. Graphical Operations was shipped to work with Windows 3.1 as well as OS/2. The combination of early operating systems and pre-Pentium PCs limited client performance and, subsequently, the career of Graphical Operations, according to DiCecco.

But the AS/400’s development is not limited to "waiting for Microsoft’s brain trust to come along with the next great thing," DiCecco points out. "Microsoft provides the base enablers, but the AS/400 progresses from there."

Java and the Internet

"If I had to single out the one technology that is most important to the AS/400, its customer and its business partners, it’s Java," Kiscaden says.

So it’s no wonder IBM is making substantial investments in Java technology. In one swoop, Java "gets us a GUI for all the applications, gives us portability across all platforms in the industry, and gives us an OO language to go along with our object-based system, which we’ve never really externalized," Kiscaden says. "We have the object-based characteristics in the operating system, but we’ve never really reflected them in the RPG and COBOL languages."

The whole industry believes OO programming is the way it’s going to keep pace with the functional needs and the maintenance costs of programming, Kiscaden adds. "We are fundamentally shifting our root application environment from RPG to Java," he says. "We’ve put the IPCS on to accommodate server consolidation. But server consolidation is not the target of our platform, it’s one of the value-add differentiators of our application platform."

Java’s momentum will certainly continue at a rapid pace, says Chris Lategan, CEO of Advanced BusinessLink Corp. (Kirkland, Wash.). "The definitive moment for users comes when they actually try something and see that it works," he says. "The responsibility is with the vendors to keep demonstrating to the market that Java is ready to go. I’m absolutely convinced that the AS/400 marketplace is past the day of distributing the client out to users."

Remote Access

Though the need for access to the AS/400 from remote locations continually increases, one vendor insists "remote connectivity on the AS/400 has been a priority since day one." It is simply a case where the AS/400 users’ needs have changed over the past 10 years – there are more resources to connect with and users require more flexibility, says Kevin Segriff, product manager with Perle Systems Inc. (Westmont, Ill.). Users now need connectivity beyond simple AS/400 access because shops are now implementing other servers and other resources within their centralized environment.

One of the AS/400 strengths, dating back to the System/36 and System/38, is the capability to set up remote sites without serious or significant management requirements, either at the remote site or the central site, according to Segriff. "Users like their AS/400s because they can manage 30 or 40 remote sites with a staff of four to six people," he says. In a non-AS/400 environment, that’s not even a consideration, "you need significantly more people and resources."

"The strength of the AS/400 has always been its database and its reliability, but I think it’s also the capability of putting users out at remote sites without having to have significant resources dedicated to keep them up and working," Segriff says.

And now … the IPCS

The IPCS is significant for a number of reasons, such as simplicity, performance and server consolidation. Formerly known as File Server Input/Output Processor (FSIOP), IPCS enables the consolidation of a number of server types, including Windows NT, Lotus Domino, OS/2 Warp and Novell NetWare. The IPCS permits the consolidation of up to 16 servers on a single AS/400, allowing for an entire network to be monitored from a single source.

It’s clear Microsoft wants to carve out a bigger and bigger piece of the midrange business and they want to grow NT into that role, according to NLynx’s Robillard. However, stand-alone NT cannot provide the kind of reliability and performance in terms of transaction processing and database-intensive applications that the OS/400 environment can.

Connecting with the Future

AS/400 networking and connectivity will continue to develop along with the needs of the user base. Many trends already underway – such as network and server consolidation, broader Internet access and thin client computing – still have a long way to go and will continue to occupy vendors in the market.

"I see a continued requirement of being able to have the AS/400 live in the enterprise information system and deliver a common user interface for the user," Wall says. "From a client standpoint I think we’re moving from a world that’s been dominated by internal users – people who’ve been trained on 5250 screens – to a world where we’re going to have our partners and ultimately our customers online and those same kind of 5250 applications are probably going to be inadequate to reach those people."

One of the key ways for companies in the midrange market to remain relevant to users is to produce solutions that adapt easily to new technology, according to Advanced BusinessLink’s Lategan. "IP will continue to be the foundational protocol for a long, long time," he says. "I think that’s simply because of popularity. IP doesn’t have to be technically elegant. It just is totally ubiquitous right now – everybody runs over IP."

With regard to consolidation, Gartner’s Pultz believes companies will increasingly demand converged network services that include voice, data and video on a single network. AS/400 shops must be sure to preserve mission-critical application processing even when consolidating networks, he adds.

Another trend Pultz points to is the move toward application-centric networks and, subsequently, policy-based networking. "Application-centric networks are designed to ensure there is a quality of service for AS/400 applications," he says. With policy-based networking, the network is aware of applications and employee hierarchy, and resources are assigned differently for different workers.

"Thin client will find a home in the IBM world," adds Robillard. "This evolution would have happened in the IBM world regardless of what was occurring in the Wintel world, and much of this can be attributed to the Internet."

Terminal users are increasingly finding they need access to the Internet or corporate intranets to obtain online resources and e-mail. How ironic is it that the AS/400’s terminal-steeped tradition will continue to procreate, thanks to the marriage of thin-client computing with the Internet.