There is provided, for example, a method, comprising: transmitting, by a wireless device, a data accumulation request to an access node of a wireless network, wherein the data accumulation request comprises at least one downlink accumulation rule for accumulating downlink data; receiving a message from the access node, wherein the message indicates that there is downlink data in the access node for the wireless device; and triggering a service period for receiving the downlink data from the access node upon determining, on the basis of the received message, that the downlink data satisfies the at least one downlink accumulation rule.