Explain the difference between CFB and OFB modes of block cipher operation. What mode is more reliable? Why?

Hints:

OM-1 IV Shift register 64-bits is bits X64 Shift register 64-bitss bits X64 Shift register 64-bits sbits 64 IV Shift register 64-s bitss bits t64 Shift register 64-3 bitss bits 64 Shift register 64-bitss bits 64 K K K Encrypt X64 Encrypt X64 Encrypt 864 KEncrypt X64 K- K-Encrypt X64 Encrypt X64 Discard 64-bits Select bits s Select s bits Discard 64-bits Select s bits s Discard 64-bits P P2 PM Select Discard s bits | 64-bits Select Discard s bits 64-s bits Select Discard s bits 64 - s bits 8 P P2 PM C CM C2 (a) Encryption C CM C2 (a) Encryption IV CM-1 Shity register 64-bits s OM-1 bits Shift register 64-bits s bits 164 Shift register 64-bits bits IV Shift register 64-s bits s bits Shift register 64-s bitss bits 64 Shift register 64-bits s bits 64 K K Encrypt 864 Encrypt 64 64 Decrypt 64 K K K Select bits Discard 64-bits Decrypt 64 Select & bits | Discard 64-bits Encrypt X64 Select s bits Discard 64-bits Encrypt 64 Select Discard bits/ 64-bits Select s bits Discard 64-bits Select s bits Discard 64-bits -CM S -C2 - P PM P2 (b) Decryption Figure 3.13 s-bit Cipher Feedback (CFB) Mode P PM P2 (b) Decryption Figure 3.14 s-bit Output Feedback (OFB) Mode