Feeds

Time to balance WS-* and REST

Relative needs

High performance access to file storage

The argument rages on, with the REST advocates mostly talking loudest. Here, for instance, are ringing condemnations of WS-* from an IBM employee and a Microsoft employee. It's positively alarming to see how closely they agree. Just for balance, here's Steve Vinoski's take. He's a practical distributed systems architect, an expert in CORBA and most other types of middleware, and quite impartial. But perhaps we should give the last word to Sanjiva Weerawarana, an ex-IBMer who now seems inclined to call down "a plague on both your houses". He's right, of course: WS-* and REST both have their strengths and weaknesses, and neither is perfect for everything.

When confused by too much detail, it pays to go back to first principles. First of all, we should ask ourselves, what are web services exactly? Sad to say, the honest answer is that no one knows - or, at least, not everyone agrees. Some definitions stress the use of XML, while others insist on SOAP or WSDL. Some implementations directly support CICS, Java EE or grids, while others are deliberately lightweight and easy to use.

The next question is whether web services should be designed to fit in as painlessly as possible with existing object-oriented applications and frameworks, or to work as efficiently and cleanly as possible across existing networks? The two objectives are hard to reconcile, if not actually incompatible. Then perhaps we should ask how much it should cost to use web services? Should it be free, as originally envisaged, or should it require the purchase of complicated, expensive proprietary tools and middleware?

Without answering these questions, it is impossible to choose between WS-*, XML/HTTP, REST, and other technical approaches. Even distributed object systems like CORBA, COM+, and RMI work well in certain particular types of application - for instance, those running on fast, reliable networks within a single administration and security domain. They lie at one end of the spectrum, with REST at the far end and WS-* in the middle. REST is particularly suitable for very large networks with huge numbers of clients and servers, where clients may also be servers and vice versa, and where it is convenient to model all operations as reads and writes directed to individual URIs. As for WS-*, its sweet spot lies in systems bigger than those that use distributed objects, and whose networks are further flung, slower, less reliable, and possibly divided between different administrative domains.

Don't expect conclusive answers to this many sided debate any time soon. When it comes to web-scale distributed systems, we simply don't know enough yet about what works and what doesn't. Besides, web services are still a solution in search of new problems. That's always harder than trying to solve a known set of requirements.®

Tom Welsh is a senior consultant with Cutter Consortium's Enterprise Architecture advisory service. Tom has been following OMG and its specifications since 1992.

High performance access to file storage

More from The Register

next story
Android engineer: We DIDN'T copy Apple OR follow Samsung's orders
Veep testifies for Samsung during Apple patent trial
Windows 8.1, which you probably haven't upgraded to yet, ALREADY OBSOLETE
Pre-Update versions of new Windows version will no longer support patches
Microsoft lobs pre-release Windows Phone 8.1 at devs who dare
App makers can load it before anyone else, but if they do they're stuck with it
Batten down the hatches, Ubuntu 14.04 LTS due in TWO DAYS
Admins dab straining server brows in advance of Trusty Tahr's long-term support landing
This time it's 'Personal': new Office 365 sub covers just two devices
Redmond also brings Office into Google's back yard
Half of Twitter's 'active users' are SILENT STALKERS
Nearly 50% have NEVER tweeted a word
Windows XP still has 27 per cent market share on its deathbed
Windows 7 making some gains on XP Death Day
Internet-of-stuff startup dumps NoSQL for ... SQL?
NoSQL taste great at first but lacks proper nutrients, says startup cloud whiz
US taxman blows Win XP deadline, must now spend millions on custom support
Gov't IT likened to 'a Model T with a lot of things on top of it'
prev story

Whitepapers

Securing web applications made simple and scalable
In this whitepaper learn how automated security testing can provide a simple and scalable way to protect your web applications.
Five 3D headsets to be won!
We were so impressed by the Durovis Dive headset we’ve asked the company to give some away to Reg readers.
HP ArcSight ESM solution helps Finansbank
Based on their experience using HP ArcSight Enterprise Security Manager for IT security operations, Finansbank moved to HP ArcSight ESM for fraud management.
The benefits of software based PBX
Why you should break free from your proprietary PBX and how to leverage your existing server hardware.
Mobile application security study
Download this report to see the alarming realities regarding the sheer number of applications vulnerable to attack, as well as the most common and easily addressable vulnerability errors.