I can write a subroutine (or can it be a helper program ? ) for Kerberos authentication I only need to find the right place in squid to call it. Markus "Wisskirchen, Dominik /Z22" <Dominik.Wisskirchen@xxxxxxxxxxxx> wrote in message news:B23E3DD4D422AC469FB6DAD5E28D3FB401636504@xxxxxxxxxxxxxxxxxxxxxxxxxx Hello all, Can I use a ISA Server 2006 as a cache_peer for Squid 2.6 using a Kerberos or NTLMv2 authentication? NTLM(v1) has been disabled due to security reasons. I want the Squid proxy to use the ISA Server as an upstream server, but the ISA Server only allows NTLMv2 or Kerberos authentication. To clarify: I do NOT want clients of the Squid proxy to be authenticated, only the Squid proxy itself shall authenticate to the ISA Server. (Kerberos/NTLMv2) (no authentication) ISA 2006 -----------------Squid 2.6--------------------Clients (without Kerberos/NTLMv2 support) Thanks for any answers in advance Dominik