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# AES.GCM

The Advanced Encryption Standard (AES) Galois Counter Mode (GCM) cipher
suite.

```
enum GCM
```

## Topics

### Storing the output

[`SealedBox`](/documentation/CryptoKit/AES/GCM/SealedBox)

A secure container for your data that you can access using a cipher.

### Getting a nonce

[`Nonce`](/documentation/CryptoKit/AES/GCM/Nonce)

A value used once during a cryptographic operation and then discarded.

### Securing the plaintext message

[`seal(_:using:nonce:)`](/documentation/CryptoKit/AES/GCM/seal(_:using:nonce:))

Secures the given plaintext message with encryption and an
authentication tag.

[`seal(_:using:nonce:authenticating:)`](/documentation/CryptoKit/AES/GCM/seal(_:using:nonce:authenticating:))

Secures the given plaintext message with encryption and an
authentication tag that covers both the encrypted data and
additional data.

### Decrypting and verifying the message

[`open(_:using:)`](/documentation/CryptoKit/AES/GCM/open(_:using:))

Decrypts the message and verifies its authenticity.

[`open(_:using:authenticating:)`](/documentation/CryptoKit/AES/GCM/open(_:using:authenticating:))

Decrypts the message and verifies the authenticity of both the
encrypted message and additional data.

## Relationships

### Conforms To

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

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