Windows 7 worked on Windows 7. These were broadly divided into "core operating system" and "Windows client experience", in turn organized into 25 teams of around 40 developers on average. In October 2008, it was announced that Windows 7 would also be the official name of the operating system. There has been some confusion over naming the product Windows 7, while versioning it as 6.1 to indicate its similar build to Vista and increase compatibility with applications that only check major version numbers, similar to Windows 2000 and Windows XP both having 5.x version numbers. The first external release to select Microsoft
Windows Vista of the redesign of the network stack, Windows Firewall has been upgraded, with new support for filtering both incoming and outgoing traffic. Advanced packet filter rules can be created that can grant or deny communications to specific services. The 64-bit versions of Vista require that all device drivers be digitally signed, so that the creator of the driver can be identified. While much of the focus of Vista's new capabilities highlighted the new user-interface, security technologies, and improvements to the core operating system, Microsoft also adding new deployment and maintenance features: Windows Vista includes a large number of new application