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  "title" : "SecurityMessage.CipherSuite.Version"
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# SecurityMessage.CipherSuite.Version

A version of the cipher suite protocol.

```
enum Version
```

## Overview

The version determines the format of the protocol information string that the system uses for HPKE key derivation. Use [`SecurityMessage.CipherSuite.Version.version1`](/documentation/AccessoryTransportExtension/SecurityMessage/CipherSuite-swift.enum/Version/version1) when creating security messages. On your accessory, format the protocol information as `{cipherSuite}-Version1-{identifier}` when deriving HPKE keys.

## Topics

### Identifying protocol versions

[`case version1`](/documentation/AccessoryTransportExtension/SecurityMessage/CipherSuite-swift.enum/Version/version1)

Version 1 of the cipher suite protocol.

## Relationships

### Conforms To

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

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

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

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

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

---

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