Preparing for an IPv6 world with LXI instruments

IPv6 has been an evolving, relatively mature, but poorly-adopted internet protocol standard for a number of years. The original motivation for IPv6 was to work around exhausting the IPv4 address space used by the original internet protocol. Already, the last large free blocks of IPv4 addresses have been allocated to particular geographic regions for them to sub-allocate within their regions. In many regions of the world, IPv6 addresses will soon become the only addresses available for remote access to new devices, including remote access to instruments supporting LAN control connections. IPv6 brings advantages of its own, as well. Stateless address autoconfiguration (SLAAC) makes it easier to set up IPv6 devices with stable global and local IPv6 addresses with nothing but IPv6-enabled routers, which are becoming much more common. Coupled with LXI-supported zero configuration hostnames via mDNS, that reduces the administration required to set up LAN-based instruments in a test system. In practical terms, IPv4 will continue to see wide use, so LXI instruments will maintain support for IPv4 while adding support for IPv6. Most LAN-based instruments are used only on the local subnet, which can continue to use and re-use the local DHCPsupplied IPv4 addresses for instruments. It is only when subnets become IPv6-only or when instrument connections must be made over the WAN that IPv6 becomes more important. This paper describes key aspects of IPv6 as they relate to instrument control and how the LXI Consortium has adopted a new LXI IPv6 standard to make observing and controlling LXI instruments over IPv6 easy. Among the IPv6 aspects covered are real-world experiences setting up IPv6 access to instruments with existing networking infrastructure.