authentication



here is my client-server authentication scheme:

Ka=Key of Alice
Kh=Key derieved from hash of R1+R2 , + means to concatenate
Ks=Random session key
R1=Nonce of Alice
R2=Nonce of Server
A=Alice
K=Server

A->K : { A , R1 }Ka
K->A : { R2 , { Ks , R1 }Kh }Ka
A->K : { R2 }Ks

Will it work?

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