$)$ A bank uses a columnar transposition cipher to securely transmit account details between

branches. The encryption key is the word "MONEY", and the plaintext message is

"TRANSFER $5000$ TO ACCOUNT $12345".$ However, an attacker has intercepted the

following ciphertext: "TNORC$0$ST$5$T$0$AUEP$50$O$100$ASRFA$3$N$25".$

a$)$ Decrypt the ciphertext and retrieve the original message using the columnar transposition

technique.

b$)$ Evaluate the security of columnar transposition ciphers in financial communication systems

and suggest modern alternatives that can improve security.