In a packet-based data network, packets are duplicated and a sequence number is inserted into each duplicate packet, where the duplicate packets are transmitted along two different paths from a source node to a destination node in the network. Depending on the implementation, the source node inserts different types of sequence numbers into the duplicate packets, and the destination node processes those sequence numbers accordingly to determine whether to accept or reject each received packet. In certain implementations, the number of sequence bits allocated to each packet is smaller than the size of the effective sequence number for the packet as interpreted by the destination node.