Although web services are in their infancy, early adopter users have already identified their positives and negatives and are finding ways of translating issues into benefits.
Web services were heralded as creating a new dawn of flexible IT infrastructures, frictionless data transfer and integrated business services.
But now that enterprises are implementing the technology, what pros and cons are emerging on the ground?
Pros: responsive and cost-effective
Application development and integration is the benchmark benefit of web services today.
"The primary application of web services and the major benefit that we see today is simplifying, and reducing the cost of, the integration of applications and data," says Tom Murphy, marketing director for web services technology specialist Cape Clear Software.
Murphy's opinion is supported by survey findings. For example, a reduction in application development time scored the highest in a survey of 200 delegates who recently attended Butler Group's web services and integration symposium.
These IT professionals like web services because they increase their ability to respond rapidly to the business environment.
Controlling IT costs comes a close second for them, with web services seen as an effective means of moving to paying for a service when it is required.
How this benefit manifests itself in practice can be seen by work at BT.com.
The telecoms portal needed to provide speedy online validation of customers to eliminate the wait for an e-mail before they could access the site.
Its approach was to develop a web service that compared bill data with information supplied by the customer.
BT.com took delivery of the service within a week and able to go live less than five weeks after the initial request was made.
A conventional mid-tier deployment would have taken double the time and the cost of producing the web service was 25% of the development price for hand coding.
The bank ABN Amro made a similar saving when it rolled out a web portal in six months with a team of just three Java developers.
Cons: immaturity and security issues
The problems associated with web services centre on the immaturity of the technology: whether or not they will be overcome is a moot point.
They manifest themselves particularly when users consider external integration projects.
Security is one of the biggest concerns.
Conventional web applications operate at the edges of the corporate network and employ technological mediators, such as e-mail and web servers, to carry data in and out.
They are like a country with strict border controls.
Although most web services are currently being deployed only within the organisation, eventually they will permit the free flow of traffic across an effectively unbounded, seamless network.
The real advantage of web services lies in opening up networks to ensure the free exchange of information.
Security, then, must address who is traversing the network, rather than the way firewalls check who is coming into the network. To date, such identity-based security is rare.
"For the foreseeable future, web services will focus on integration within the firewall, inside the enterprise," says Nathaniel Martinez, research manager with analyst firm IDC's European software group.
Without a mechanism for efficiently processing identities, web services will never gain widespread adoption in the marketplace.
"It is important that an enterprise is able to simply and inexpensively establish the identities of users requiring access.
"The password on its own is no longer a secure authentication mechanism," Mark Blowers, senior research analyst at market analyst Butler Group.
"There are still major concerns about security, reliability and availability of third-party services, especially where these are 'anonymous' or unknown until run time," adds Charles Southwood, UK country manager at software and services supplier Candle.
"No one is yet willing to bet their business on a transaction model that is not planned, proven and clad in cast iron."
A related issue is that of performance. Inside the firewall, bottlenecks can be identified and by-passed relatively easily.
However, when the network incorporates external web services, the corresponding complexity and reduction in control means that performance is much harder to guarantee.
"A move towards guaranteed service levels could, perhaps, see the industry working towards certifying web services performance," says Mike Lucas, regional technology manager at application developer Compuware.
"Yet who would be responsible for certifying them?
"We have seen the emergence of various discrete web services communities, but they could cause more confusion and questions than they do clarification, especially if they all have different expectations.
"It may be more effective to agree on a set of performance metrics that would be used to measure the performance of each web service."
Maintaining performance levels has other knock-on effects. For example, web services often increase the demand for processing power at the server and client ends.
"Client PCs must manage multiple, simultaneous data streams, heavy XML parsing, and heightened background computing loads from encryption, virus checking and other operations," says Alan Priestley, strategic marketing manager at Intel's server group.
"If an organisation does not consider this when implementing web services then productivity could be affected."
A rather different issue stems from the fact that IT functions on legacy systems tend to be located at the core host rather than the client PC.
"The challenge for IT is to transform this host functionality so it can be combined with new initiatives like web applications, packaged applications or portals," says Ron Grevink, director of integration strategy at host integration company WRQ.
A service-oriented architecture, in which web services are created to be reusable, is one way around this. Such reusable web services are stored in a repository or service registry, ready for other deployments.
Finally, the web services standards have yet to be defined.
"The complexity of the Soap message format and XML technologies have been noted," says Russ Thornton, cofounder of integration specialist m35.
"The skills-set still tends to be with the supplier community as opposed to the user community.
"Chief information officers should be investing not only in web service products but also in educating their staff today."
Pros and cons at a glance
Faster application development
Lack of standards