Request Model involves a process-flow for Request Management
Make Self-Help available
Typical process flow would be
User initiates request
Request is accepted (or rejected as per process) by Service Desk
Necessary Approvals (if not pre-approved) are sought by SD
SD may also order the components (h/w or s/w) if out of stock
When approvals and components are ready, SD delivers the service to user
Service request is closed by SD