Table 4 Key-sharing process in proposed work (ECC + CA Rule 90).
Step | Action | Who Does It? | Key Type Used | Purpose |
|---|---|---|---|---|
1. Key Generation | Generate ECC key pairs (PrivateKey, PublicKey) using the secp256r1 curve. | Both parties (Alice & Bob) | Private Key (secret), Public Key (shared) | Establish secure identities for key exchange. |
2. Key Exchange | Exchange public keys while keeping private keys secret. | Alice \(\rightarrow\) Bob, Bob \(\rightarrow\) Alice | Public Key | Enable secure shared secret computation. |
3. Shared Secret | Compute shared secret via ECDH: Alice: PrivateKey_A * PublicKey_B, Bob: PrivateKey_B * PublicKey_A | Both parties | Private Key + Peer’s Public Key | Derive identical secret without transmitting it. |
4. CA Key Creation | Convert shared secret to integer, feed into CA Rule 90, and generate CA_Key. | Both parties | Shared Secret (from ECDH) | Add chaos-based randomness for stronger encryption. |
5. AES Encryption | Use CA_Key to initialize AES-128 (with IV) for image encryption/decryption. | Encryptor / Decryptor | CA_Key (derived) | Secure image data with lightweight encryption. |
