Patent ID: 6590895
Filing Date: 2003-07-08
Classification: H04L

Abstract:
A method of managing transmission of data units in a flow from a first device to a third device via a second device in a communications network, comprising:receiving at the second device at least some of a sequence of data units transmitted from the first device; determining which, if any, of the data units of said sequence are missing data units that have not been received at the second device; transmitting the at least some data units of said sequence that have been received at the second device toward the third device; transmitting from the second device to the first device at least one request for retransmission of the missing data units of said sequence; after transmitting the request for re-transmission of the missing data units, continuing to receive data units of the sequence from the first device and to transmit the received data units toward the third device, such that data units appearing later in the sequence than the missing data units are received and transmitted toward the third device before the re-transmitted missing data units; tracking the data units of said sequence that were not received at the second device by maintaining a record of predetermined range N to N+M that indicates, starting with data unit N, which data units were not received at the second device; and ceasing further efforts to obtain a lost data unit N once data unit N+M+1 is received at the second device.