1# MD Overview and Algorithm Specifications
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3The message digest (MD) algorithm allows a fixed-length digest to be generated from data of arbitrary size by using the hash algorithm. The MD algorithm is also referred to as a hash algorithm or a one-way hash algorithm.
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6When the same digest algorithm is used, the generated digest (hash value) has the following features:
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9- The same message always results in the same hash value.
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11- The digest generated is of the fixed length no matter the length of messages. (The digest length is determined by the algorithm used).
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13- It is almost impossible to find two different messages with the same hash value. (The probability still exists, depending on the length of the digest.)
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16## Supported Algorithms and Specifications
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18The **Supported Type** column in the following table lists the algorithm to be used when an **Md** instance is created.
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20| MD Algorithm| Supported Type| API Version|
21| -------- | -------- | -------- |
22| HASH | SHA1 | 9+ |
23| HASH | SHA224 | 9+ |
24| HASH | SHA256 | 9+ |
25| HASH | SHA384 | 9+ |
26| HASH | SHA512 | 9+ |
27| HASH | MD5 | 9+ |
28| HASH | SM3 | 10+ |
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