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Comment: Dual Homing Failover and IPv6 address aggregation (Score 1) 382

by billstewart (#49543191) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

Yeah, that turned out to be one of the big problems with IPv6 address aggregation - sounds great in the ivory tower, doesn't meet the needs of real customers, which is too bad, because every company that wants their own AS and routable address block is demanding a resource from every backbone router in the world.

IPv6's solution to the problem was to allow interfaces to have multiple IPv6 addresses, so you'd have advertise address 2001:AAAA:xyzw:: on Carrier A and 2001:BBBB:abcd:: on Carrier B, both of which can reach your premises routers and firewalls, and if a backhoe or router failure takes out your access to Carrier A, people can still reach your Carrier B address. Except, well, your DNS server needs to update pretty much instantly, and browsers often cache DNS results for a day or more, so half your users won't be able to reach your website, and address aggregation means that you didn't get your own BGP AS to announce route changes with, but hey, your outgoing traffic will still be fine.

My back-of-a-napkin solution to this a few years ago was that there's an obvious business model for a few ISP to conspire to jointly provide dual-homing. For instance, if you've got up to 256 carriers, 00 through FF, each pair aa and bb can use BGP to advertise a block 2222:aabb:/32 to the world, and have customer 2222:aabb:xyzw::/48, so the global BGP tables get 32K routes for the pairs of ISPs, and each pair of ISPs shares another up-to-64K routes with each other using either iBGP or other local routing protocols to deal with their customers actual dual homing. (Obviously you can vary the number of ISPs, size of the dual-homed blocks, amount of prefix for this application (since :2222: may be too long, etc.)

Comment: IPv6: Longer addresses + magic vaporware (Score 1) 382

by billstewart (#49543107) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

IPv6 was originally supposed to solve a whole lot of problems - not only did it have longer addresses (which ISPs need to avoid having to deploy customers on NAT, and in general to avoid running out of address spaces and crashing into the "Here Be Dragons" sign at the edge), but it was also supposed to solve a whole lot of other problems, like route aggregation, security, multihoming, automatic addressing, etc.

A lot of that turned out to be wishful thinking, e.g. the hard part about IPSEC tunnels is the key exchange and authentication, not building the tunnels, route aggregation didn't really work out because enterprises weren't willing to use carrier addresses instead of their own, and small carriers also wanted their own addresses instead of sharing their upstream's address space, or if it wasn't wishful thinking, it was addressing problems that IPv4 found other solutions for, like DHCP for automatic addressing.

And while NAT is a hopeless botch, it does provide a simple-minded stateful firewall as default behaviour, while IPv6 users need explicit firewalling to get the same security with real addresses (which they needed to do anyway, but especially if you're using tunnels, you have to be sure to put it in all the right places.

Comment: Future: IPv4 via NAT, IPv6 Native (Score 1) 382

by billstewart (#49543037) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

Back when I was closer to the ISP business, the general plan of most consumer ISPs was to start supporting IPv6 (once they had all their hardware and operations support systems able to manage it - it's amazing how many moving parts there are), and migrate most users to dual-stack, with NAT for IPv4 plus native IPv6, or else to use NAT IPv4 with tunneled IPv6.

Comment: Comcast was ahead of many US ISPs on IPv6 (Score 1) 382

by billstewart (#49542999) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

Comcast may have lots of other issues as an ISP, such as banning customers from running server at home, and monthly usage caps (if they still do that), but they were ahead of most other US consumer ISPs on taking IPv6 seriously.

(My ISP supports IPv6 over tunnels, but doesn't run native dual-stack, at least on telco DSL. And I really should get around to actually trying it out, but I haven't...)

Comment: Re:Yes, Old SATA SSD, not Rotating Disk (Score 1) 159

by billstewart (#49542969) Attached to: New PCIe SSDs Load Games, Apps As Fast As Old SATA Drives

Anonymous Coward was asking if the "old SATA drives" referred to old SSD drives that use SATA (which wouldn't be too surprising if it were almost as fast), or old rotating hard disks that use SATA (which would be really surprising to find it faster than SSD.) Google results for the X25-m say yes, it's an SSD, just a bit older one that uses SATA instead of PCIe.

Comment: Re:Idiotic (Score 1) 590

I remember when the Death Penalty was reinstated in the US.

The proponents, in the popular media, said that it was necessary for the drug war - and would only be used in extreme cases, for Drug Kingpins, and Serial Killers, where there was no doubt about guilt, because there was overwhelming evidence, and full confession.

As it turns out - this was absolutely not the case.

Comment: Re:Without them completely? No (Score 1) 363

by jafac (#49472569) Attached to: Can Civilization Reboot Without Fossil Fuels?

We don't have shit for a way to replace the fertilizer supply,

. . . I see what you did there.

If the starvation dying doesn't get you, the lack of medical supplies is going to curb another large portion of our population.

Any future speculated "civilization" is going to be very different from our current one, that is for sure. Life is going to be much less convenient. I still believe that "advancement" will be possible.

Comment: Re:No (Score 1, Interesting) 363

by jafac (#49472503) Attached to: Can Civilization Reboot Without Fossil Fuels?

Your air conditioning and clothes dryer are modern conveniences.

Solar can power modern technology. But a future, speculated civilization will have a much less convenient, and lower standard of living. Just because life is inconvenient, doesn't mean society can't advance. We discovered how to split the atom before we had antibiotics. (antibiotics are not really a necessary component of an advanced, modern civilization. They are a convenience. Yes, it is inconvenient when people die young from preventible diseases. But we can still get to the point where we could - in the future, transition from solar to nuclear; for cases where that scale of electrical power generation is necessary to continue to advance).

The problem with our current civilization is that people have placed convenience (and profitable enterprise enabling hoarding of personal wealth) beyond basic common-sense principles of long-term survival (sustainability). There are really two routes here. We can either choose sustainability over convenience. Or Nature will choose, for us (and we lose both). We may never get convenience back. But I think it's very doable to get sustainability back. Even without ready access to petroleum.

Another huge benefit we've had from petroleum is the advances to agriculture from the Haber-Bosch process. Basically; this converts energy into food (through synthesis of atmospheric Nitrogen into fertilizer). This is what revolutionized agriculture in the early 20th century, and allowed our population to explode like a test-tube full of hearty yeast and grape-juice. Economists argue that that population explosion was necessary for our modern, advanced civilization. I believe that thinking to be biased by short-term thinking. This path has absolutely devastated our options, as far as a sustainable future goes. Eventually, the yeast drown in their own waste (CO2 and alcohol - so fitting). That's what will happen to us. I am thankful that whatever civilization comes after us, will not be permitted by readily-available fossil fuels, to repeat this horrible mistake, because they will need to struggle to peak-out at a global population of 1 Billion. Yes - life will be inconvenient, nasty, brutish, and short. But civilization will remain sustainable.

Comment: Re:Easy explanation (Score 1) 97

by jafac (#49471717) Attached to: Being Overweight Reduces Dementia Risk

Well, from my admittedly "selection-biased" perspective, I *do* know some elderly people. Yes, the ones with dementia are quite miserable. The ones who get into a really severe state, generally don't "last" more than a year. (thankfully). I also know a couple of elderly people (in their 90's) (and, I've had some relatives, as well, up in their late-90's) who are totally mentally sharp. They have hobbies, activities, and some health problems, but nothing horrible. I don't even know how people like this die. :)

I've also known a couple of guys who, in their 70's, got cancer . . .
And I've known a couple of people who suffered from strokes, and heart problems.

Unfortunately, strokes and heart problems can lead to dementia SYMPTOMS. (until the heart just quits, of course). Take care of your ticker, and your blood pressure.

Of all these; I'd say cancer was probably the easier death.

But my first choice is "none of the above, and have a happy, full-life into my 90's". Whether I have any friends or family or not.

Dementia would be last on my list of "ways to go peacefully". Maybe 2nd to last, because ALS fucking sucks too. (just ask Stephen Hawking).

Comment: Re:No Bad management is causing the drought (Score 2) 173

"price water properly" is probably a good, and simple solution.
But there are many practical barriers that make this nearly impossible.
For one, there are treaties and water-rights already assigned. These involve multi-state government agreements, and there really is not an authority mechanism in existence that can address these in a unified way.
For two, there are political entanglements (regulatory capture, and officials who are basically corporate AG lapdogs).

This is one of those Utopian Ideals issues, where you think that if some magical authority came in, and put a gun to everyone's head and said: you will give up your advantageous, privileged bargaining position, and now you will pay what everyone else pays for water (and be willing to pull the trigger when they refuse or fight back) - it would solve the problem.

Basically, we need a Stalin. Or a Pol Pot.
Or we need to magically convert into a race of altruists.

Comment: ROI depends on investment as well as return (Score 1) 139

by billstewart (#49384253) Attached to: IT Jobs With the Best (and Worst) ROI

The original material talked about salaries and job titles; it didn't say how much investment it took to develop the skills to get those titles. Some of those skills are things you can add quickly; others take a long time or access to appropriate work environments. (For instance, learning PHP is quick, and Ruby on Rails isn't that hard either. But while you can learn SQL and MySQL pretty quickly, becoming a DBA really needs access to real-world databases and workloads that you're involved in administering.)

Comment: Radio Shack Closing Around Them (Score 1) 92

by billstewart (#49368043) Attached to: Arduino Dispute Reaches Out To Distributors

I started playing with Arduinos a couple of years ago. You ordered them by mail order at the time. Eventually Radio Shack started carrying them, which made it easier for anybody to pick one up (and while I live in Silicon Valley, if I needed a few resistors or LEDs or simple components to go with them, it was often easier to stop at Radio Shack than Fry's or mailorder.) Now they're fighting over the name, and Radio Shack is going out of business.

Fear is the greatest salesman. -- Robert Klein