Microsoft ISA 2006 is being offered in two versions: ISA 2006 Standard and ISA 2006 Enterprise. While ISA 2006 Enterprise Version is intended for use in large corporate environments with several firewalls and integrated load balancing, the standard version is meant to replace existing firewall solutions in smaller systems or to be a solution just behind an existing firewall implementation. The changes and additions in ISA 2006 are nowhere near as extensive as those undertaken between ISA 2000 and ISA 2004.
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