Abstract: A mechanism for dispatching a sequence of packets via a telecommunications network includes a queue for packets for transmission and a queue controller responsive to receipt of a new packet for transmission to compare parameters of the new packet to parameters of any packet already in the queue, the queue controller determining whether to queue or drop the new packet depending on the result of the comparison(s). The queue can be implemented as a linked list of packet entries with individual pointers to the respective packets concerned. The queue entries can include details relating to the packet including data relating to the information flow and also the packet identity. In a TCP environment, the flow information can include the source IP address and the source TCP port, as well as the destination IP address and the destination TCP port. The identity information can include sequence numbers and acknowledgement numbers for the packet concerned.

Abstract: A dispatch mechanism is provided for dispatching data units, (e.g. datagrams or packets) divided into one or more fragments, via a telecommunications network. The dispatch mechanism includes a queue for queuing fragments for transmission. It further includes a queue controller operable when a fill level of the queue exceeds a threshold value to discard fragments of data units for which a fragment has not already been queued and to add to the queue fragments of data units for which a fragment has already been queued. The dispatch mechanism maintains a record of data units which are to be transmitted (that is when one fragment of the data unit has already been passed for despatch) and a record of data units which are to be dropped (that is data units for which a fragment has already been dropped). The dispatch mechanism enables more effective use of network capacity by reducing the possibility of incomplete data units being transmitted over the network.