The Utility Web Service provides a projection service and lets you change the coordinate system and datum transformation of a geometry or envelope.
The Utility Web Service includes the following capabilities:
http://arcweb.esri.com/services/v2/Utility.wsdl
https://arcweb.esri.com/services/v2/Utility.wsdl
Note: HTTPS is available if you need added security to call ArcWeb Services. The Authentication Web Service and other ArcWeb Services must be accessed with the same IP address for the authentication token to be valid.
Interact with a live sample of a Utility Web Service client. For information on creating clients for ArcWeb Services, including downloadable code for JavaServer Pages (JSP) with Glue, C# ASP.NET, and VB ASP.NET, see Introducing client samples.