Ok, before continuing, I'll back up a little, so that those less familiar with these concepts can see what I'm talking about.
First, Mulicasting. This is a technology which permits you to stream data to multiple people, without overloading the network or the server. Exactly one copy is transmitted by the server, and the network makes duplicates of the data as and when necessary.
As streaming data (such as newscasts, music, concerts, etc) is now a significant part of the Internet, AND one of the biggest problems is overloading, due to the attempt by servers to send a copy to each and every recipient in turn, multicasting offers some significant advantages.
(A classic example was the Leonid meteor shower, a few years back. Webcams in areas that could see the shower were hopelessly overloaded and many collapsed entirely, due to the demand. With multicasting, you can serve one person or one billion. It's all the same to the computer.)
Next comes IPv6. This is a complete re-write of the Internet protocol, providing support for much larger addresses, transparent migration from one network to another, automatic configuration, flow control, security, simpler packet structure (leading to faster communication), "anycasting" (where you can request a service where you don't know, or don't care, what the server's address is) and greater flexibility for programmers.
You don't need to understand every single one of these advantages to notice that there are a lot of them. About the only one that is likely to matter to the average user is the migration. This allows people with hand-helds, lap-tops and other small computers to be on-line while travelling, without interruption. As soon as you reach the limits of one ISP, the computer will automatically switch to another, ensuring that all your existing connections stay up and running. (For the technical purist, this is Mobile IP, with IP Migration.)
QoS is the most interesting of all, but there isn't a particularly good website, at least as far as I know. QoS basically tries to distribute available network resources between applications, such that no one application can hog the network, and/or applications which need extra resources are guaranteed those resources.
Typical QoS software includes CBQ (Class Based Queueing - allocate resources by the type of service used) and RSVP (Reservation Protocol - reserve a certain percent of network resources for the use of a specific application).
So far, so good. So why are these failures?
This is where we move from the technical to the political. The main reason these aren't in common use is that they do allow more efficient use of the Internet.
X-Files! No, not quite. Let me explain. Multicasting means that you could have one server transmit radio-style or TV-style broadcasts to an unlimited number of users. Since it's not restricted by the speed of the connection, there is no reason why anyone would need to buy fast connections from ISPs, for this kind of work.
As a result, deploy multicasting and you kill one of the bigger sources of income for these people. Further, since there's no way of determining how many people are receiving, you can't do billing by access.
This last point has a flip-side, too. Since there IS no way of determining how many people are receiving, there's no means for advertisers to know how large their audience is. They'll know if it's zero, or not zero, but that's it. Result: since many such netcasts depend on advertisers to survive, they have absolutely NO incentive to obliterate their bank balance, just to provide a superior service to more people.
IPv6 is moribund for fairly similar reasons. The very strengths of IPv6 are killing it in the eyes of the people who need to buy into it, if it is to survive. Mobile IP? Switching ISPs??? You think that any ISP in its right mind is going to encourage you to buy a rival service?!
Then, there's anycasting. If you're not tied to a specific resource, but can scan the net for the one best-suited to your needs and location, where is the benefit in paying some ISP for some specific one that you might end up never using, because it's just not suitable?
Simpler headers & simpler network topology mean simpler, faster routers. Cisco is having a hard enough time as it is, without their top-of-the-line cash cows being turned into hamburger.
Built-in security? That is going to go down well with companies selling expensive crypto technology, isn't it? IPv6 uses IPSec, which in turn uses DES3, which is reasonably fast and practically unbreakable, at least at the present time.
Now we move onto the last part. QoS. By now, you should see that most ISPs and Internet Backbone providers would rather be eaten by lions than provide superior-quality service for less money. That's not out of some kind of paranoia, it's simply that these people are in business to make money, not hand it out.
And THAT is the point of this entire article. Those in a position to deploy or promote superior technology are ALSO required by shareholders and the profit motive to not do so. Ignoring the money factor would be suicide for any company, which (in turn) makes any new technology they deploy meaningless, because they're no longer there to give anyone access to it.
This leads me to the ultimate question -- is the Internet too important to leave to the private sector?