In this recent post to his blog Bogdan Albei looks at using the Zend Framework to "quickstart" the development of a simple web service.

Web services are software systems designed to support interoperable machine-to-machine interaction over a network. Nowadays if you want to connect external systems, you probably want or have to use web services. What I will discuss here is how to get your own SOAP web service up in minutes.

Bogdan looks at creating a simple controller with actions for displaying a WSDL file and for handling actions that might come in. Sample code is provided as well as example code.