Most Linux systems come with open source OpenSSH preinstalled.
Enterprise Client - Tectia SSH Client
Tectia SSH client is used by many enterprises for system administration and for running legacy text-based applications. It is the leading commercially supported SSH Windows Client on the market.
We provide our Tectia SSH customers technical support services on three different service levels. For more information of available support services, see our support pages.
Enterprise SSH Server - Tectia SSH Server (Windows, Linux, Unix, zOS)
For business-critical applications, we recommend Tectia SSH. It is available for Windows, Unix, Linux, and IBM mainframes. It supports standards-compliant X.509 PKI, and smartcard authentication, including PIV and CAC cards and DoD PKI.
Tectia SSH shares no code base with the open source version, and it supports key management on all platforms. For premium customers we offer 24x7 support.