---
title: distinguishedNames
framework: foundation
role: symbol
role_heading: Instance Property
path: foundation/urlprotectionspace/distinguishednames
---

# distinguishedNames

The acceptable certificate-issuing authorities for client certificate authentication.

## Declaration

```swift
var distinguishedNames: [Data]? { get }
```

## Discussion

Discussion This value is nil if the authentication method of the protection space is not client certificate. The returned issuing authorities are encoded with Distinguished Encoding Rules (DER).

## See Also

### Getting protection space properties

- [authenticationMethod](foundation/urlprotectionspace/authenticationmethod.md)
- [host](foundation/urlprotectionspace/host.md)
- [port](foundation/urlprotectionspace/port.md)
- [protocol](foundation/urlprotectionspace/protocol.md)
- [proxyType](foundation/urlprotectionspace/proxytype.md)
- [realm](foundation/urlprotectionspace/realm.md)
- [receivesCredentialSecurely](foundation/urlprotectionspace/receivescredentialsecurely.md)
- [serverTrust](foundation/urlprotectionspace/servertrust.md)