Cart Start
gives control to the user who selects products from federated but independent web based stores.  The user owns a shopping cart, a desktop application, that keeps a list of products. The products, set aside for the user's purchase, come from one or more stores. ( One cart, many stores. )

Federated Stores The stores are federated. They are independent centers of expertise, sales, and customer relations. But, they commonly utilize a server that connects their stores to the user controlled shopping cart.

Shared Inventory CartStart addresses the problem of shared inventory. It uses a processes of item ticketing for reserving products for customers. A customer may release the ticket or purchase the product. Tickets may also be assigned expirations. Web pages showing products update their inventory counts periodically.

There are three basic parts to CartStart:

1. Shopping Cart.  When a user selects a product from a CartStart federated store, it is relayed to his desktop. The item appears in his shopping cart list. If the product was in the list before, the quantity of the selection is incremented. Also, the source of the shop selection, the web page, is inserted into a list of bookmarks; so that, the user may return to the selection page during different sessions. When the user makes his purchase, checks out his cart, the tickets for the selected items are passed through the CartStart server to the stor distributors. Shipping, or product movement, is relayed back to the user shopping cart. The purchased products are moved from the shopping cart list to the list of items with expected delivery.

2. Store Front Templates   Each store will select a set of products for display and purchase. CartStart template pages provide the formatted entries for products. The pages are set up to converse with the server and to update product information on a periodic basis. In particular, the pages are setup as script pages for modules, such as PHP, so that the shopping cart can initiate a session, validated by a user id and password, on any bookmarked CartStart page.

3. CartStart Server. The CartStart server directs traffic between the federated store fronts and the connected user shopping carts. When a user selects a product from a federated web store, the product identity is passed from the server side pages through a socket to a server port. The server keeps active threads for the shopping carts. When product identity message runs through a store front thread, the user identity, carried in the message, keys the shopping cart thread for message delivery. The server then either pushes the message to the user shopping cart, or it makes the message available so that the shopping cart may poll for the message.