DID

PUBLIC-KEY

DID-TA

${\left\{Hash\left(\text{DID},\text{PUBLIC-KEY},\text{DID-TA}\right)\right\}}_{k_{\text{TA}}^{-1}}$

$D_a^0$

$k_a^0$

$D_{{\text{TA}}_1}$

${\left\{H\left(D_a^0,k_a^0,D_{{\text{TA}}_1}\right)\right\}}_{k_{{\text{TA}}_1}^{-1}}$

$D_a^1$

$k_a^1$

$D_{{\text{TA}}_1}$

${\left\{H\left(D_a^1,k_a^1,D_{{\text{TA}}_1}\right)\right\}}_{k_{{\text{TA}}_1}^{-1}}$

$D_b$

$k_b$

$D_{{\text{TA}}_2}$

${\left\{H\left(D_b,k_b,D_{{\text{TA}}_2}\right)\right\}}_{k_{{\text{TA}}_2}^{-1}}$

$D_c$

$k_c$

$D_{{\text{TA}}_3}$

${\left\{H\left(D_c,k_c,D_{{\text{TA}}_2}\right)\right\}}_{k_{{\text{TA}}_3}^{-1}}$

$⋮$

$⋮$

$⋮$

$⋮$