A Complete Hierarchical Key Management Scheme for Heterogeneous Wireless Sensor Networks

Table 2

Communication overheads, unit is mJ.

Type	Broadcast	Broadcast	Unicast	Number of; nodes	Maximum (uni)	Average (uni)
	128-bit	256-bit	128-bit
𝑑=2,ℎ=2	0.0064	0.0075	0.0852	2	0.0355	0.0426
𝑑=2,ℎ=3	0.0149	0.0174	0.3551	6	0.0923	0.0592
𝑑=2,ℎ=4	0.0320	0.0373	1.1221	14	0.2059	0.0802
𝑑=2,ℎ=5	0.0660	0.0770	3.1105	30	0.4332	0.1037
𝑑=2,ℎ=6	0.1342	0.1565	7.9964	62	0.8877	0.1290
𝑑=2,ℎ=7	0.2706	0.3155	19.5862	126	1.7967	0.1554
𝑑=2,ℎ=8	0.5433	0.6336	46.4019	254	3.6147	0.1827
𝑑=2,ℎ=9	1.0887	1.2696	107.3052	510	7.2507	0.2104
𝑑=2,ℎ=10	2.1795	2.5417	243.6559	1022	14.5228	0.2384
𝑑=3,ℎ=2	0.0852	0.0994	0.2983	3	0.0852	0.0994
𝑑=3,ℎ=3	0.2769	0.3229	1.7896	12	0.2983	0.1491
𝑑=3,ℎ=4	0.8520	0.9936	8.1810	39	0.9374	0.2098
𝑑=3,ℎ=5	2.5773	3.0056	33.1077	120	2.8548	0.2759
𝑑=3,ℎ=6	7.7532	9.0418	125.1444	363	8.6071	0.3448
𝑑=3,ℎ=7	23.2809	27.1501	453.0253	1092	25.8640	0.4149