This document describe experience gained while implementing the SMOA Computing Service [1], a component which 
development was steered by the 
following OGF specifications: 
• GFD 108 - OGSA® Basic Execution Service Version 1.0 [2] 
• GFD.114 - HPC Basic Profile, Version 1.0 [3] 
• GFD.135 - HPC File Staging Profile, Version 1.0 [4] 
In addition to comments on those specifications, this document presents possible  extension to the Basic Execution 
Service: a separate interface for managing Advance Reservations based on the BES-Factory port.