Patent ID: 8787312
Filing Date: 2014-07-22
Classification: H04L,H04W

Abstract:
1. In a first base station adapted to receive media access control (MAC) layer packet data units (PDUs) from a radio network controller (RNC) relating to at least a traffic flow relating to a given user entity and forwarding PDUs to said user entity, wherein the transmission to the given user entity is adapted to be handed over to at least a second radio base station, a method comprising: continuously updating, by the first base station, at least a data structure relating to MAC layer PDUs of a priority queue of the given user entity, which PDUs are last transmitted from a protocol layer in the radio network controller, whereby at least some of said PDUs may not be received by a corresponding protocol layer in the user entity yet, the data structure indicating a number of MAC layer PDUs that remain to be transmitted from the first base station or remain to be acknowledged by the user entity; and in response to receiving a predetermined signal from the radio network controller requesting the data structure, transmitting, from the first base station to the radio network controller, a current value of said data structure, wherein the first and second radio base stations and the radio network controller operate according to a standard where MAC layer PDUs comprise MAC-d PDUs from a radio network controller (RNC) relating to at least a traffic flow relating to a given user entity and MAC-hs/MAC-ehs PDUs transmitted from the first or the second base station to said user entity, and the step of continuously updating the data structure (UNACK_MACD_CNT) comprises: determining a first value representing the number of MAC-d PDU's stored in a flow buffer; determining a second value representing the number of MAC-d PDU's transmitted in a MAC-hs MAC-ehs PDU's up to and including the earliest sent unacknowledged MAC-hs/MAC-ehs PDU; and summing the first and second values to produce a third value being the sum of the first and second values, wherein for the case of a MAC-d PDU is split such that a first part of a MAC-d is sent in a first MAC-ehs and the second part of the MAC-d is sent in a subsequent MAC-ehs, only the latter contributes to the UN-ACK_MACD_CNT, whereas all other MAC-ehs stemming from the splitted MAC-d PDU do not contribute to UNACK_MACD_CNT.