tailieunhanh - Microsoft ISA Server 2004 Firewall phần 1

Microsoft ISA Server 2004 is a hybrid stateful packet-inspecting, circuit-filtering, and application layer proxy firewall. | Microsoft ISA Server 2004 Firewall Microsoft ISA Server 2004 is a hybrid stateful packet-inspecting circuit-filtering and application layer proxy firewall. By hybrid we mean that it can provide any of those functionalities at any given time based on the traffic it is receiving. If it has an application filter for the given protocol or application it will function as an application proxy firewall for that traffic. If it does not it will resort to either stateful packet inspecting or circuit filtering as required. In addition ISA Server 2004 includes virtual private networking VPN and caching capabilities allowing it to function as an all-in-one device that as one would expect integrates pretty cleanly with Microsoft-centric environments. Before we look at the features of Microsoft ISA Server 2004 let s talk about the elephant in the room namely the perception that ISA Server 2004 is not a real firewall. This perception is largely the result of misinformation lack of education regarding the product and simple dislike disregard of anything Microsoft being remotely considered as a security solution. When you look at ISA Server 2004 with an honest and skeptical eye it is relatively easy to cut through many of the fallacies and realize that Microsoft ISA Server 2004 is an effective and practical firewall solution. First on the list of misconceptions is the statement that any firewall running on a Windows platform cannot be secure. This is just not factually accurate. All firewalls run on some operating system. In the case of firewalls such as the Cisco PIX Firewall or Check Point SecurePlatform the operating system is specialized and hardened for use on a firewall. Windows out of the box is not designed to be run on a firewall but it can be effectively secured and hardened following the principles of running the minimum required services and functionality necessary to operate as a firewall alone. Some excellent resources detail how to effectively secure the underlying .