(a)
A ---> B : {{"To: Bob", msg}a }B

(b)
A ---> B : {{Alice, msg}B, #msg}a 

(c)
A ---> B : {{"A ---> B", msg}B, #msg}a 
A ---> B : {{"A ---> B", msg}a }B 

(d)
A ---> B : {{{msg}a }B, #B}a 

(e)
A ---> B: {{{msg}B, #msg}a }B

Example 2: Five independent and equivalently secure fixes for the naive sign-and-encrypt problem: (a) signing the recipient's name in the plaintext; (b) encrypting the sender's name into the plaintext; (c) incorporating both names in the message body; (d) signing and encrypting the plaintext and then signing the ciphertext; (e) reencrypting the ciphertext's signature.