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# kCFStreamSSLLevel

Security property key whose value specifies the stream’s security level.

```
let kCFStreamSSLLevel: CFString
```

## Discussion

By default, a stream’s security level is `kCFStreamSocketSecurityLevelNegotiatedSSL`. For other possible values, see <doc://com.apple.documentation/documentation/CoreFoundation/cfstream-socket-security-level-constants>.

---

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