Patent ID: 7111086

Claim:
A method for transferring a data set between a transfer-initiating subsystem and a target via an intermediate subsystem, a transfer-executing subsystem, and a channel, where: the transfer-initiating subsystem follows a transfer protocol in which the data set is transferred as a series of packets, and transfer of at least one subsequent packet is contingent on completed transfer of at least one previous packet; data transfer between the transfer-initiating subsystem and the transfer-executing subsystem takes place via the intermediate subsystem; the transfer-executing subsystem initiates data transfer via the channel upon receipt of a transfer request and of identification of the data set to be transferred; the method comprising: within the intermediate subsystem, A) receiving a first one of the packets from the transfer-initiating subsystem; B) signaling to the transfer-initiating subsystem that the transfer of the first packet is still pending, so that the transfer-initiating subsystem at least temporarily delays submission of subsequent packets to the intermediate subsystem; C) issuing to the transfer-executing subsystem a transfer request and identifying for the transfer-executing subsystem the data set to be transferred, whereupon the transfer-executing subsystem attempts transfer of the data set; D) upon sensing a completion signal from the transfer-executing subsystem indicating completed transfer of the data set, i) signaling to the transfer-initiating subsystem completed transfer of the first packet; ii) receiving subsequent packets from the transfer-initiating subsystem and, for each, signaling to the transfer-initiating subsystem completed transfer of each subsequent packet.