A method of propagating data packets in a network of nodes is disclosed. The method, implemented at one of the nodes, includes: generating at least one data packet of a first type; collecting a set of data packets of the first type during a first time period, the set including the at least one generated data packet and at least one data packet of the first type received from one or more first nodes in the network; and determining a mapping of the data packets of the set to a plurality of neighbouring nodes connected to the node, the mapping indicating an expected time of relay of each data packet of the set to neighbouring nodes, wherein determining the mapping includes determining at least one of: a first sub-mapping which allocates any two data packets having a same source for relay to different subsets of the neighbouring nodes; and a second sub-mapping which assigns different expected times of relay to any two data packets that are generated at the node or received by the node from the one or more first nodes in a same time interval.