bc</td>
<td>MCrypt, OpenSSL</td>
<td>A safe default choice</td>
</tr>
<tr class="row-odd"><td>CTR</td>
<td>ctr</td>
<td>MCrypt, OpenSSL</td>
<td>Considered as theoretically better than CBC, but not as widely available</td>
</tr>
<tr class="row-even"><td>CFB</td>
<td>cfb</td>
<td>MCrypt, OpenSSL</td>
<td>N/A</td>
</tr>
<tr class="row-odd"><td>CFB8</td>
<td>cfb8</td>
<td>MCrypt, OpenSSL</td>
<td>Same as CFB, but operates in 8-bit mode (not recommended).</td>
</tr>
<tr class="row-even"><td>OFB</td>
<td>ofb</td