The big four gotchas

If you're looking for a good read on the "gotchas" that come out of a Web services deployment, check out this latest article from Mike Lehmann, Oracle's Web services guru.
Mike narrowed down the list to four of the most painful gotchas:

• Interoperability: "Although interoperability best practices for Web services are becoming better understood for lower-level protocols like SOAP and WSDL, issues at the more recently emerged quality-of-service level for security, reliability, and policy are not as well understood. As such, service enabling these applications in a consistent and maximally interoperable fashion is a key concern for enterprise architects."
• Performance: "Any deployment architecture for Web services must include a comprehensive plan to understand the performance characteristics of the service end points and the clients using those service end points. Typically the performance needs to focus on two areas, throughput and latency."
• Quality of service: "Web services typically take advantage of the same quality-of-service characteristics such as clustering, reliable messaging, and security available from server vendors for classical multi-tier applications."
• Manageability: "As a Web services application is deployed, classic management issues begin to appear. These issues can include monitoring and diagnostics, service-level agreements, policy management, centralized auditing and logging, and consolidating around a single identity management infrastructure."