A method of a node accessing an unlicensed channel comprising: performing, by the node, a determination of whether an unlicensed channel the node requires access to is expected to be busy or idle in a period during which the node wants to transmit data, or in a period during which the node wants to perform clear channel assessment prior to transmission of data from the node; and accessing the channel in a manner dependent upon a result of the determination, the accessing the channel including performing a clear channel assessment of the channel.