Version 1.6.0 is a major release that incorporates back-ported features from the 2.0 branch, which is still under development. It also fixes a number of issues.

New features and improvements (including those listed under 1.5.0):

• Apple Silicon (MacOS ARM64) native support via universal binary. ZeroTier now requires the very latest Xcode to build.
• Linux performance improvements for up to 25% faster tun/tap I/O performance on multi-core systems.
• Multipath support with modes modeled after the Linux kernel's bonding driver. This includes active-passive and active-active modes with fast failover and load balancing. See section 2.1.5 of the manual.
• DNS configuration push from network controllers to end nodes, with locally configurable permissions for whether or not push is allowed.
• AES-GMAC-SIV encryption mode, which is both somewhat more secure and significantly faster than the old Salsa20/12-Poly1305 mode on hardware that supports AES acceleration. This includes virtually all X86-64 chips and most ARM64. This mode is based on AES-SIV and has been audited by Trail of Bits to ensure that it is equivalent security-wise.

Bug fixes:

• Managed route assignment fixes to eliminate missing routes on Linux and what we believe to be the source of sporadic high CPU usage on MacOS.
• Hang on shutdown issues should be fixed.
• Sporadic multicast outages should be fixed.

Known remaining issues:

• AES hardware acceleration is not yet supported on 32-bit ARM, PowerPC (32 or 64), or MIPS (32 or 64) systems. Currently supported are X86-64 and ARM64/AARCH64 with crypto extensions.