An Enhanced Lightweight Dynamic Pseudonym Identity Based Authentication and Key Agreement Scheme Using Wireless Sensor Networks for Agriculture Monitoring

. 2019 Mar 6;19(5):1146. doi: 10.3390/s19051146

Step 1:

The

U_{i}

inserts his/her own smartcard into the card reader and enters

I D_{i}

P W_{i}

and imprints

F_{i}

on a sensor device. Now, the card reader computes

R e p (F_{i}

P_{F})

X_{F}^{*}

R P W_{i}^{*} =

h (P W_{i} ‖ X_{F}^{*})

A_{i}^{*} = B_{i}

⊕

h (R P W_{i}^{*} ‖ I D_{i})

D_{i}^{*} =

h (A_{i}^{*} ‖ R P W_{i}^{*} ‖ I D_{i})

{[h (B_{i} ‖ X)]}^{*}

C_{i}

⊕

A_{i}^{*}

and verifies if

D_{i}^{*}_{=}^{?} D_{i}

. If this verification holds, then continues the process. Otherwise, the session is terminated.

Step 2:

The

U_{i}

enters new password

P W_{i}^{n e w}

and computes

R P W_{i}^{n e w} = h (P W_{i}^{n e w} ‖ X_{F})

B_{i}^{n e w} = B_{i}

⊕

h (R P W_{i} ‖ I D_{i})

⊕

h (R P W_{i}^{n e w} ‖ I D_{i})

A_{i}^{n e w} = B_{i}^{n e w} \oplus (R P W_{i}^{n e w} ‖ I D_{i})

C_{i}^{n e w} = C_{i} \oplus A_{i} \oplus A_{i}^{n e w}

and

D_{i}^{n e w} = h (A_{i}^{n e w} ‖ R P W_{i}^{n e w} ‖ I D_{i})

. Then,

{B_{i}, C_{i}, D_{i}}

are replaced with

{B_{i}^{n e w}, C_{i}^{n e w}, D_{i}^{n e w}} respectively