Node Location Privacy Protection in Unattended Wireless Sensor Networks

Algorithm 1

Message security transmission algorithm.

	INPUT: : start sensor node; k: the maximum number of loops passed;
	: routing probability; : the centripetal node set of ;
	: the centrifuge node set of ; : the loop-left (or -right) node set of ;
	, : the corresponding Vcell and Gcell in which is located;
	: random function;
	OUTPUT: target sensor node;
	PROCEDURE:
(1)	while do
(2)	;
(3)	if then
(4)	if & then
(5)	randomly choose a node from , let
(6)	else
(7)	randomly choose a node from , let
(8)	if then
(9)	let be the subset that is bigger than
(10)
(11)	else
(12)	let be the subset that is smaller than
(13)
(14)	else
(15)	let ’s state be 0
(16)	randomly choose a node from , let
(17)	if then
(18)	let be the subset that is smaller than
(19)
(20)	else
(21)	let be the subset that is bigger than
(22)
(23)	return nj