Through the fog... Buying an application server

App servers aren't always the easiest thing to explain to the rest of the board. They're also not always the easiest part of the IT jigsaw to get hold of and use, as Quocirca analyst Bob Tarzey explains...

Application servers are becoming an essential component of a networked computing environment, as more and more applications are written to run on an application server platform, rather than directly on the underlying operating system. Most users do not get too excited about them but know they are needed to make networked applications available and run efficiently.

A quick scan of available information would suggest options are limited – first you chose between either Microsoft .Net or Java 2 Enterprise Edition (J2EE) platform as your base technology. Then, if you opt for J2EE, you choose between one of the two market leaders, BEA’s WebLogic or IBM’s WebSphere. Then just compare the features, performance and pricing, make your selection – job done.

Well, in theory, you do have a bit more choice – and the starting point for making that choice should not be the application server but the application. This is not just because it is the application that visibly adds value to your business but because the chosen application will often dictate your choice of application server.

Fortunately or unfortunately (depending on your viewpoint) applications are not always easily switched from one application server to another. Siebel has two completely different versions of its product, one for .Net and one for WebSphere. But even if an application vendor chooses to work with the J2EE platform alone, it is often still not possible to simply substitute one J2EE application server for another. This is because application vendors often make use of the application server’s extended features. For example, PeopleSoft has versions of its product for both WebSphere and WebLogic. Other application servers are not supported. Surprise, surprise the Oracle Ebusiness suite will only run with Oracle 9i/AS application server. For the record, SAP uses its own proprietary application server technology.

Having selected an application you could be forgiven for thinking, with branding like, ‘Powered by WebSphere’ or ‘Built on BEA’, that your newly acquired application will come ready with the application server included. Not so. Some application vendors do work exclusively with a given application server and may embed it in their product, with a royalty paid to the application server vendor included in the cost. These vendors are in the minority and often the application server supplied will be a limited version restricted for use with the given application. Less than 30 per cent of IBM’s ISVs work exclusively with WebSphere and the figures for BEA are probably not dissimilar. So, the application server usually has to be purchased separately.

Where application vendors stray from the standard, they may do so for good reasons but you should make sure these are detailed so you know the issues that will arise if you want to make a change at a later date. It is possible for vendors to write their applications adhering strictly to the J2EE standard so that they are portable across different application servers. This is most commonly the case when the application is not mission-critical and does not need to make use of the features of the application server that are beyond the standard.

Some vendors will supply their application with an open source application server such as JBOS or Tomcat. If these are too limited to run your application, you can choose to replace them with another J2EE compliant application server. Your choice is not limited to the market leaders.

Oracle 9i/AS and SunOne currently vie for third and fourth place in the application server market. Both their products are J2EE-based. Oracle 9i/AS is based on code line from Swedish product OrionServer, also available from the primary vendor, IronFlare. However, Sun is hedging its bets and also backing BEA WebLogic.

Sybase’s EA Server and Borland’s Enterprise Server AppServer Edition can be purchased via these vendors’ usual channels, although their products are most commonly sold embedded in third-party applications – more choices for the application vendor as well as the end user.

Novell is always looking for ways to add value to its large installed base of NetWare users – look out for announcements about its J2EE compliant exteNd Application Server.

If you are compelled to buy a certain application server to run your application, you do not necessarily have to buy it from the application server vendor. They all have resellers, of course, but you could also try speaking to your hardware supplier. No surprises that IBM recommends its own WebSphere but HP and Sun both have both agreements with BEA for supplying WebLogic. By the way, both the HP and Sun hardware platforms can support IBM’s WebSphere but don’t expect either of them to get too excited about it when negotiating a deal.

Is it possible to standardise on an application server? In theory yes but you would have to select your applications very carefully. The likelihood is that you will end up with a number of application servers in your organisation, simply because you run a variety of applications. You may even end up running more than one application server on the same hardware server. This is unsatisfactory but may be acceptable for non-mission critical applications. For those applications that are critical to your enterprise you are going to have to review the options offered by the application vendor and make the necessary additional investment.

The bottom line is that the application server market is far from commoditised. The capabilities of the different vendors’ products vary, which makes portability hard, despite the standards. The vendors are increasingly offering new features and extensions to their products. The big drivers at the moment are integration and web services.

While the development of these products continues apace, the eventual winners are not certain. BEA and IBM are clear leaders today, both with more than 30 per cent market share. For the time being you may as well accept that you will have multiple application servers within you organisation and that your purchasing decisions will be dictated, in part, by your application vendor. If your application server supplier falls by the way side at some time in the future, further commoditisation and standardisation of application servers by that time will hopefully be your saviour.

Quocirca will be producing a full report on purchasing application servers that can be obtained by sending an email to info@quocirca.com.

**Quocirca is a leading, user-facing analyst house known for its focus on the 'big picture'. For a full summary of its activities see www.quocirca.com, or reach the company's founding directors by emailing quocirca@silicon.com.

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For Quocirca's 'What's the fuss about...?' series for silicon.com, see this page

And for their earlier 'Surviving the Recession' series, see this page.