In terms of user authentication ShareKnowledge uses Microsoft SharePoint authentication models.
Here're the links to the MS documents on SAML-token based authentication:

As it's part of the athentication setup client needs to:

  1. Have the 'Identity provider security token service' (IP-STS) running on their side.  On premise ADFS server, Enterpise application in Azure AD or another simmilar application could be used to run the service.  Since SAML token-based authentication in SharePoint Server uses the SAML 1.1 protocol, the IP-STS server must be able to issue SAML 1.1 Security Tokens
  2. Add ShareKnowledge applcation as 'Relying party security token service'(RP-STS) entry to the IP-STS server
  3. Register the dedicated DNS record that will be used to access the ShareKnowledge
  4. Issue the SSL certificate for the dedicated DNS
  5. Provide IP-STS server signin url
  6. Provide the Identifier associated with the ShareKnowledge RP-STS entry
  7. Provide the Security Token Signing Certificate issued by the IP-STS server

    Here's the example of configuration using ADFS services 3.0 as authentication provider
    http://www.sharepointpals.com/post/Configuring-ADFS-as-Authentication-Provider-For-SharePoint-2013-Web-Application

    Here's one of the ways to use Azure as authentication provider
    http://helpdocs.shareknowledge.com/unsorted/using-azure-ad-for-sharepoint-authentication