Described is a network device (203) configured to operate as a first node in a communications network (200) for a user device (201) initiating a small data transmission communication session through a target node (202) in the communications network (200), the network device (203) being configured to, upon receiving a request from the target node (202), send a message to the target node (202), the message comprising an indication of small data transmission configuration information (401, 506) for the user device (201). A corresponding network device (202) configured to operate as a target node is also described.