The irony is that pretty much all the silicon out there has supported IPv6 for the last 10 years, and what's holding it up is the software.
This is because when you design a chip, you have to take into account what your customers will be using it for in a few years time, but for software, it's all about what your customers want yesterday. Since IPV6 has always been 'just around the corner', it gets into the hardware but not all the software.
Its not clear what level of 'hardware' you are talking about.
For most gadgets, the only hardware related to networking you will find is a chip that does ethernet and talks to the jack for you. Everything above (like IP) is done in software.
I'm talking about routers, from the big devices in your datacentre/telco down to your dsl or cable home gateway. There's only a limited amount I can say about this ( at least, without having to think hard about I am allowed to say) but there really is a lot of silicon out there that knows what the layout of an IP packet is.
A NIC that talks ethernet doesn't mean it's in the hardware. It's more about the ASICs on the ports to handle high traffic rates. The NIC can send the packet on the wire, but inserting the IPv6 headers is done in hardware with ASICs. This is the difference between millions of packets per second versus tens of thousands.
Part of the problem with software is that there's so much of it. You don't just have the stuff running on routers, you've got your customer management system, logging + auditing, DNS etc.
There's no point in an ISP offering IPv6 if its routers support it but their back office management software doesn't.
Support as in "can process ipv6 traffic?" Or support as it "can process a volume of ipv6 traffic with performance and practical feature characteristics on par with its handling of ipv4 traffic?"
If you mean the former then sure, but that's not the point. The latter is what hampers adoption and I assure you, most hardware produced in the last 10 years does not support ipv6 to the degree that it does ipv4.
I mean the latter, but I'm talking about just the silicon, not the complete product produced by (say) a switch vendor, which perhaps explains the difference.
No, he's saying "the chips are in the switches, but networking vendors may not have mature support in the operating system". Think Cisco IOS as an example of the software that has to support the protocol in addition to what the silicon can do.
This is because when you design a chip, you have to take into account what your customers will be using it for in a few years time, but for software, it's all about what your customers want yesterday. Since IPV6 has always been 'just around the corner', it gets into the hardware but not all the software.