What are web services?
In business-speak, web services are all about linking up different websites so they work for customers in an intelligent way. Simple.

Yes, too simple. Give me an example.
OK. If you use a web-based diary and you then book theatre tickets through lastminute.com, the magic of web services automatically updates your diary. And for business users, web services technology will be used to enable some of the B2B exchanges which have so far struggled to live up to their potential.

How is it different from ecommerce?
It’s not about ecommerce per se. It’s about protocols that allow different websites to link together in a whole range of intelligent ways. The end result should be they become less painful to use, when buying or doing other things.

What are the drawbacks then?
The biggest problems are without doubt security and privacy. The idea of web services relies on masses of data, usually customer data such as credit cards, being shared in some way across the internet. Finding a way to prove securely that someone is who they say they are over the web is probably the biggest challenge, and so far the biggest source of controversy.

What about the technology?
The most important aspect of web services is the basic protocols: XML (eXtensible Mark-up Language), SOAP (Simple Object Access Protocol), UDDI (Universal Description Discovery and Integration) and WSDL (Web Services Description Language). They are a set of standards that ensure everyone, across the industry, whatever technology they use, can communicate some basic ideas.

What do these protocols do?
XML is a way of describing content on the internet – not just where it should be on a page or what it should look like, but also explaining it. It is the basis of all of the other protocols. SOAP is just a way of using XML to make different programs and operating systems communicate with each other. UDDI is a phone directory for computers, telling them where to locate certain services. WSDL is a recognisable way to describe certain web services.

That’s quite enough protocols for one day
Be grateful for small mercies. They make everyone’s lives much easier and are also pretty much the only part all the technology vendors agree upon.

Ah, the vendors. I knew they would poke their ugly heads in. Who’s important?
The vendor with the most reach here, and the grandest vision, is Microsoft. Its .NET technologies, which are starting to become available, will offer the easiest route into this for many. Its technology is based on a new development environment, C# – which is not dissimilar to Java – and its authentication engine called Passport, already used to run Hotmail login.

There must be some competition?
Of course. Sun is probably the loudest, with its Sun ONE project, but AOL, HP and IBM are also making noises. Very broadly the market splits into two halves – the Microsoft area based on .NET, and everyone else working around an environment running Java on application servers.

What does that mean to me? What path should I go down?
Quite honestly, probably neither at the moment. Sun will have you believe its vision is deliverable right now but it does entail a lot of in-house development. Microsoft is still a long, long way from getting the technology out there. Neither will in reality make it happen for some time.

So why should I care?
Web services will be the most important trend in computing over the next five years. Being aware of the issues today means you are well placed to take full advantage of web services when they become ubiquitous – and they will be everywhere, just under the surface, linking everything together.

For a complete list of Cheat Sheets type ‘CS1’ into the silicon.com Search

**Essential Links**
From the silicon.com archive
Cheat Sheet: Microsoft Passport
big idea: Why .NET matters
.NET gamble: Microsoft’s major offensive explained

External Links