Method for controlling re-transmissions

1 . An apparatus comprising:

at least one processor; and

at least one memory, said at least one memory stored with computer program code thereon, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to perform:

providing a counter in a protocol entity;

using a timer, by the protocol entity, in order to retransmit a poll;

incrementing said counter only in response to expiry of the timer implying a new transmission by (i) a transmission buffer and a retransmission buffer both being empty aside from transmitted Radio Link Control (RLC) service data unit (SDU) or RLC SDU segment awaiting acknowledgments, or (ii) no new RLC SDU or RLC SDU segment being able to be transmitted due to transmission window stalling;

skipping incrementing of the counter in response to the expiry of the timer implying a new value for a Poll send state variable by (i) the transmission buffer not being empty, or (ii) transmission window stalling;

providing a Radio Resource Control (RRC) layer of said apparatus or a second apparatus with an indication in response to the counter reaching a predetermined threshold value; and

resetting the counter in response to resetting the timer,

wherein the protocol entity maintains a retransmission counter associated with a packet, and wherein the counter is separate from the retransmission counter,

wherein said indication to the RRC layer is distinguishable from an indication sent upon the retransmission counter of the protocol entity reaching its threshold value,

wherein said indication is configured to be associated with a report for Minimization of Drive Tests (MDT),

wherein the apparatus is configured to increment said counter only for signaling radio bearer SRB0 and not for any of signaling radio bearers SRB1, SRB2, and SRB3,

wherein the protocol entity is a Radio Link Control (RLC) protocol Acknowledged Mode (AM) entity, and

wherein, when the apparatus is a gNB Distributed Unit (DU) and the second apparatus is a gNB Central Unit (CU), the indication is provided from the gNB Distributed Unit (DU) to the gNB Central Unit (CU) using an F1 Application Protocol message.