This document discusses optimizing data collection in wireless sensor networks. It begins by introducing the concepts of wireless sensor networks and data collection trees. It then discusses using Breadth-First Search (BFS) for data collection and proposes a Parallel Data Collection in BFS (PDCBFS) approach. PDCBFS allows nodes to aggregate data from themselves and child nodes into a single packet to send to the parent node, reducing transfer time compared to individual packets in BFS. The document analyzes and compares the performance of BFS and PDCBFS in terms of data collected and delay required for collection.