Patent ID: 6401136
Filing Date: 2002-06-04
Classification: G06F

Abstract:
A method of communicating between a source device and a destination device over an external communication link utilizing a queue-to-queue transfer system, the method comprising:transmitting messages stored in a source persistent queue at the source device over the external communication link to the destination device, wherein the transmitted messages have transmitted with them an associated sequence identifier which identifies the message stored in the source persistent queue and wherein the source persistent queue maintains the messages to be transmitted and associated sequence identifiers between execution of instances of the queue-to-queue transfer system by the source device; receiving the transmitted messages and the associated sequence identifiers at the destination device in an order other than an order of the sequence identifiers of the messages and storing the received message and the associated sequence identifier in a destination persistent queue at the destination device and wherein the destination persistent queue maintains the received message and associated sequence identifier between execution of instances of the queue-to-queue transfer system by the destination device; transmitting to the source device from the destination device a commit message, wherein the commit message identifies a largest sequence identifier of consecutive sequence identifiers associated with received messages of a sequence of messages which have been persistently stored in the destination persistent queue; and making the persistently stored message in the destination persistent queue available to users of the destination device independent of whether a commit message identifying the message has been transmitted to the source device.