Protocol Type Enum
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Specifies the security protocols that are supported by the Schannel security package.
This enumeration has a FlagsAttribute attribute that allows a bitwise combination of its member values.
public enum class SecurityProtocolType
[System.Flags] public enum SecurityProtocolType
[<System.Flags>] type SecurityProtocolType =
Public Enum SecurityProtocolType
Specifies the Secure Socket Layer (SSL) 3.0 security protocol. SSL 3.0 has been superseded by the Transport Layer Security (TLS) protocol and is provided for backward compatibility only.
Allows the operating system to choose the best protocol to use, and to block protocols that are not secure. Unless your app has a specific reason not to, you should use this value.
Specifies the Transport Layer Security (TLS) 1.0 security protocol. The TLS 1.0 protocol is defined in IETF RFC 2246.
Specifies the Transport Layer Security (TLS) 1.1 security protocol. The TLS 1.1 protocol is defined in IETF RFC 4346. On Windows systems, this value is supported starting with Windows 7.
Specifies the Transport Layer Security (TLS) 1.2 security protocol. The TLS 1.2 protocol is defined in IETF RFC 5246. On Windows systems, this value is supported starting with Windows 7.
Specifies the TLS 1.3 security protocol. The TLS protocol is defined in IETF RFC 8446.
This enumeration defines the set of values that you can use to specify which transport security protocol to use. It is the enumerated type for the SecurityProtocol property. Use this enumeration to determine your transport security protocol policy when you're using HTTP APIs in the .NET Framework such as WebClient, HttpWebRequest, HttpClient, and SmtpClient (when using TLS/SSL).
The Transport Layer Security (TLS) protocols assume that a connection-oriented protocol, typically TCP, is in use.