In sensor networks, burst sensor messages are required to be transmitted along a wireless multihop routes to a sink node with no lost sensor messages and with shorter transmission delay. However, due to congestions, buffers in intermediate sensor nodes around the sink node overflow. In addition, buffers in other intermediate sensor nodes are also overflow since an intermediate node Ni is an exposed node of a next-hop node Ni+1, a previous-hop node Niâ''1 is an exposed node of Ni and Niâ''2 and Ni+2 are hidden nodes of Ni. Thus, contentions among these nodes cause less transmission opportunities and buffers in Ni may overflow. In order to reduce such buffer overflow, this paper proposes (1) a method for notification of a filled buffer to the previous-hop node and (2) a method for forwarding sensor messages to a pseudo next-hop node Ni+1 which is a neighbor node of Ni and Ni+2 for reduction of lost sensor messages and for shorter transmission delay.
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