Complex sentence: This is an attempt at documenting the undocumented NTLM authentication scheme used by Microsoft's browsers, proxies, and servers (Internet Explorer and IIS); this scheme is also sometimes referred to as the NT challenge/response (NTCR) scheme.
Split into simpler sentences: This is an attempt at documenting the undocumented NTLM authentication scheme used by Microsoft's browsers, proxies, and servers (Internet Explorer and IIS). This scheme is also sometimes referred to as the NT challenge/response (NTCR) scheme.