Patent ID: 8386323

Claim:
A method in a computing system, comprising: in a first network node: monitoring an inventory for an item offered for sale via a merchant's online ordering system, wherein said monitoring comprises receiving messages from a plurality of different sources, wherein the plurality of different sources include the merchant's online ordering system, the merchant's distribution center, and a third-party supplier, wherein the messages are sent in response to a plurality of inventory events for the item and identify the plurality of inventory events for the item, wherein at least some of the plurality of inventory events indicate current changes to the inventory for the item, and wherein at least some of the plurality of inventory events indicate expected changes to the inventory for the item; and in response to each one of the plurality of inventory events that affects an availability of the item for purchase, sending an asynchronous message to a second network node, wherein the asynchronous message identifies a corresponding availability event; and in the second network node: receiving the asynchronous messages that identify corresponding availability events; and in response to each received asynchronous message: updating an availability model which reflects an availability of the item for purchase via the merchant's online ordering system, wherein said updating comprises calculating the availability of the item for purchase dependent on the availability event, wherein the availability model reflects current changes to the availability of the item for purchase, and wherein the availability model reflects expected changes to the availability of the item for purchase; wherein the current changes to the availability of the item for purchase indicate a number of units of the item that have been physically added to the merchant's distribution center and a number of units that have been physically removed from the merchant's distribution system; wherein the expected changes to the availability of the item for purchase indicate a number of units of the item that have not yet been physically added to the merchant's distribution center, but that are expected to be physically added to the merchant's distribution center in the future, and a number of units of the item that have not yet been physically removed from the merchant's distribution center, but that are expected to be physically removed from the merchant's distribution center in the future; and evaluating a state of the availability model in order to assess availability of the item for purchase via the online ordering system.