The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 06, 2012
Filed:
Oct. 22, 2004
Fraser Gibbs, Waterloo, CA;
Charles Wang, Waterloo, CA;
Fraser Gibbs, Waterloo, CA;
Charles Wang, Waterloo, CA;
Research In Motion Limited, Waterloo, CA;
Abstract
The invention is directed to a process for transferring data packets through a protocol stack employed by the device for transmitting packets on a packet connection to a wireless network, said wireless network operating at least two, distinct wireless access technologies such as GSM/GPRS and UMTS. The packet transfer process generally comprises each layer of a protocol stack for a currently active packet connection path providing confirmation to a next, higher layer in the stack of successful reception of a data packet from that layer, thereby confirming successful transfer of the data packet through the stack. The first layer of the stack stores a copy of a transferred packet until such time as its receives confirmation from the next, lower layer of successful transfer of the packet of the stack. In the absence of such confirmation and on the occurrence of a switch (hand-off) of the packet connection to a new connection path, particularly one of a different wireless access technology, the stored packet is transferred to the protocol stack to be employed by the wireless device for the new packet connection path. Consequently, the packet transfer process avoids packets being lost on the occurrence of a switch between different technology wireless access packet connection paths.