The NetBSD Project is pleased to announce that release 4.0 of the NetBSD operating system is now available. NetBSD is a free, secure, and highly portable Unix-like Open Source operating system available for many platforms, from 64-bit Opteron machines and desktop systems to handheld and embedded devices. Its clean design and advanced features make it excellent in both production and research environments, and it is user-supported with complete source. Many applications are easily available through pkgsrc, the NetBSD Packages Collection.

Major achievements in NetBSD 4.0 include support for version 3 of the Xen virtual machine monitor, Bluetooth, many new device drivers and embedded platforms based on ARM, PowerPC and MIPS CPUs. New network services include iSCSI target (server) code and an implementation of the Common Address Redundancy Protocol. Also, system security was further enhanced with restrictions of mprotect(2) to enforce W^X policies, the Kernel Authorization framework, and improvements of the Veriexec file integrity subsystem, which can be used to harden the system against trojan horses and virus attacks. Please read below for a list of changes in NetBSD 4.0.