Microsoft Schannel (Microsoft Secure Channel)

What is Microsoft Secure Channel?

The Microsoft Secure Channel, or Schannel, is a security support package that facilitates the use of Secure Sockets Layer (SSL) and Transport Layer Security (TLS) encryption on Windows platforms.

Schannel contains specific security protocols that provide identity authentication and private communication between a client and a server. It automatically chooses the best protocol depending on the capabilities of the client and server. The protocols include TLS 1.0, 1.1 and 1.2, SSL 2.0 and 3.0, and the Datagram Transport Layer Security.

To create a secure connection, both the client and server need to obtain Schannel credentials -- X.509 certificates -- and then create a security session. Once the connection is established, information about the attributes of the credential and its context is available. If a connection is lost, it can be renegotiated by requesting a redo. Before shutting down the connection, both client and server need to perform a cleanup and delete the connection.

Microsoft Schannel applies to Windows Server 2022, Windows Server 2019, Windows Server 2016 and Windows 10.

Editor's note: This article was written by Madelyn Bacon in 2015. TechTarget editors revised it in 2023 to improve the reader experience.