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.