The supplier workspace template gives you "project capability" to manage your suppliers. You need to have SIPM in order to use the Supplier Workspace Template.
A project is a collection of information, supporting documents, tasks, and a team of users who work on the project. Depending on the solution your company has purchased, you might use one or both of the following types of Supplier Management projects:
Setting Up the Supplier Workspace Template
By default, Ariba Supplier Information Management includes a supplier workspace template with Draft status. Before your company begins managing suppliers, you must modify the template to meet your company’s business needs and publish it so that users can begin creating supplier workspace projects. For more information about working with the supplier workspace template, see the Ariba Project Template Guide.
Note: Ariba Supplier Information Management uses a single template for all supplier workspaces. You can modify a published template and upgrade existing supplier workspace projects to the new template version. Template upgrades have specific effects on various project components such as tasks and phases that are in progress and documents that have been edited, so you should plan your supplier workspace template and subsequent upgrades carefully.
The default supplier workspace template supports a specific workflow that allows your company to manage suppliers and route supplier information and approvals to specific groups of users.
There is more information on Product Help: