**3.1 AES encryption**

A plaintext of 128-bit is processed through 10 rounds. Each round contains processes like byte substitution, shift rows, mix columns, and add round key. As keys are generated using MATLAB code, only remaining system generator-based models like byte substitution, shift rows, and mix columns are discussed in this section.

Round function is one of the important processes in AES algorithm. **Figure 10** shows system generator-based model for implementing round0 function.

Round function consists of s-box, shift row, and mix column as shown in **Figure 11**. **Figure 12** shows implementation of s-box.

**Figure 13** shows implementation of shift row.

**Figure 14** shows implementation of mix column.

**127**

*High-Speed Area-Efficient Implementation of AES Algorithm on Reconfigurable Platform*

Mix column consists of group\_1, group\_2, group\_3, and group\_4. **Figure 15** shows implementation of group. Further each group consists of four multiplication blocks such as mul\_blk, mul\_blk1, mul\_blk2, and mul\_blk3. **Figure 16** shows

A cipher text of 128-bits is processed through 10 inverse rounds. Each round contains processes like inverse byte substitution, inverse shift rows, inverse mix

Inverse round function consists of inverse s-box, inverse shift row, and inverse

Inverse mix column consists of four groups, i.e., group\_1, group\_2, group\_3, and group\_4. **Figure 20** shows implementation of group. Each group consists of multiplication blocks like mul\_blk, mul\_blk1, mul\_blk2, and mul\_blk3. **Figure 21** shows

Each multiplication block consists of three multipliers mul\_2, mul\_4, and mul\_8

**Figure 17** shows implementation of inverse round function.

**Figure 19** shows implementation of inverse mix column.

and EX-OR operations. **Figure 22** shows implementation of multipliers.

*DOI: http://dx.doi.org/10.5772/intechopen.82434*

implementation of multiplication block.

**3.2 AES decryption**

**Figure 11.** *Round0.*

columns, and add round key.

mix column as shown in **Figure 18**.

implementation of multiplication block.

**Figure 10.** *System generator-based model of round function.*

*High-Speed Area-Efficient Implementation of AES Algorithm on Reconfigurable Platform DOI: http://dx.doi.org/10.5772/intechopen.82434*

#### **Figure 11.** *Round0.*

*Computer and Network Security*

A plaintext of 128-bit is processed through 10 rounds. Each round contains processes like byte substitution, shift rows, mix columns, and add round key. As keys are generated using MATLAB code, only remaining system generator-based models like byte substitution, shift rows, and mix columns are discussed in this section. Round function is one of the important processes in AES algorithm. **Figure 10**

Round function consists of s-box, shift row, and mix column as shown in **Figure 11**.

shows system generator-based model for implementing round0 function.

**Figure 12** shows implementation of s-box. **Figure 13** shows implementation of shift row. **Figure 14** shows implementation of mix column.

**3.1 AES encryption**

**126**

**Figure 10.**

*System generator-based model of round function.*

Mix column consists of group\_1, group\_2, group\_3, and group\_4. **Figure 15** shows implementation of group. Further each group consists of four multiplication blocks such as mul\_blk, mul\_blk1, mul\_blk2, and mul\_blk3. **Figure 16** shows implementation of multiplication block.
