Major new features are:
* **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.
Known issues that are not yet fixed in this beta:
* Some Mac users have reported periods of 100% CPU in kernel_task and connection instability after leaving networks that have been joined for a period of time, or needing to kill ZeroTier and restart it to finish leaving a network. This doesn't appear to affect all users and we haven't diagnosed the root cause yet.
* The service sometimes hangs on shutdown requiring a kill -9. This also does not affect all systems or users.
* 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.
* Some users have reported multicast/broadcast outages on networks lasting up to 30 seconds. Still investigating.
We're trying to fix all these issues before the 1.6.0 release. Stay tuned.
Adam Ierymenko
Grant Limberg
Travis LaDuke
Joseph Henry