$q$	A k-bit prime
$F_q$	A prime finite field
$E/F_q$	An elliptic curve $E$ over $F_q$
$G$	A cyclic additive group of composite order $q$
$P$	A generator for the group $G$
$s$	A secret key of the system
$PK$	A public key of the system, $PK=sP$
$f(x,y)$	A polynomial function that $f(x,y)$ equal to $f(y,x)$
$H_i()$	$i^{th}$ one-way hash function
$h()$	A one-way hash function
$r_i,a,b$	x’s identity, like a universally unique identifier (UUID) code
$I{D}_x$	A random number of the elliptic curve group
$S_x$	x’s elliptic curve group signature
$TID$	A transaction number which changes every round
$K_i$	A polynomial function or elliptic curve-related information
$PEK$	A session key established by personal reader and medical reader
$E_{\mathrm{x}}(m)$	Use a session key x to encrypt the message $m$
$D_{\mathrm{x}}(m)$	Use a session key x to decrypt the message $m$
$CH{K}_x$	x’s verified message
$A\stackrel{?}{=}B$	Determines if A is equal to B
$data$	Body sensor’s related sensing information
$c_i$	The session key and transaction number encrypted sensing data