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Comment: Re:Price won't come down (Score 2) 151

by Michael Woodhams (#49608721) Attached to: Tesla's Household Battery: Costs, Prices, and Tradeoffs

So I'm looking at the lithium price and I see that for $64M I can make a plant/mine which will give me $8M/year profit, and ROI of 12.5%. This looks pretty good. Then I consider than some bright spark might come up with an aluminium based battery technology which would make lithium ion batteries obsolete and could be in production 4 years from now. If this were to happen, in four years I've made back just $32M and now have a worthless mine. Therefore I decide not to invest in lithium production until I can get ROI of 20% because of the risk.

It seems to me that lithium is bound to be either overproduced (if new technology comes along) or underproduced (if new technology does not, but investors are wary of building facilities for fear it might.)

Comment: Re:AT&T Autopay - Ha! (Score 1) 228

In Germany, autopay comes with an authorization limit... basically, "if the bill is over X,€ don't autopay"

I'd prefer to see this on the autopay here in the states as well... because I'm fine with authorizing autopay for any bill less than $60... but if it reaches into the thousands, or even the hundreds, then I damn well don't want to authorize the autopay!

Comment: He was also the second Governor of New Zealand (Score 4, Interesting) 33

by Michael Woodhams (#49599863) Attached to: The Pioneer Who Invented the Weather Forecast

He quickly became very unpopular with settlers due to trying to be fair to the Maori. In one notable occasion some colonists invaded Maori land in an attempt to seize it and got massacred. (They were a poorly armed militia and on the other side was Te Rauparaha, who was so scary that to this day his haka is used by the All Blacks to intimidate their opposition.) After an investigation, Fitzroy sided with the Maori.

Comment: Re: The answer has been clear (Score 1) 390

by jd (#49575883) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

Multiple IPs was one solution, but the other was much simpler.

The real address of the computer was its MAC, the prefix simply said how to get there. In the event of a failover, the client's computer would be notified the old prefix was now transitory and a new prefix was to be used for new connections.

At the last common router, the router would simply swap the transitory prefix for the new prefix. The packet would then go by the new path.

The server would multi-home for all prefixes it was assigned.

At both ends, the stack would handle all the detail, the applications never needed to know a thing. That's why nobody cared much about remembering IP addresses, because those weren't important except to the stack. You remembered the name and the address took care of itself.

One of the benefits was that this worked when switching ISPs. If you changed your provider, you could do so with no loss of connections and no loss of packets.

But the same was true of clients, as well. You could start a telnet session at home, move to a cyber cafe and finish up in a pub, all without breaking the connection, even if all three locations had different ISPs.

This would be great for students or staff at a university. And for the university. You don't need the network to be flat, you can remain on your Internet video session as your laptop leaps from access point to access point.

Comment: The grid needs storage - not battery storage (Score 4, Informative) 329

by Michael Woodhams (#49566827) Attached to: Why Our Antiquated Power Grid Needs Battery Storage

There are many ways to 'store' electricity. Batteries are just one.

I rather like this one, a thermal storage solution. Putting air into and out of bladders under deep water is a very simple method, as is moving water up and down hills. Then there are flywheels and fixed volume compressed air storage. (The air bladders above are fixed pressure compressed air storage.) There other thermal storage possibilities, but getting good round trip efficiency is tricky.

There are non-traditional battery techniques too: flow batteries (liquid electrolytes in tanks, adding storage capacity is as easy as adding tanks full of electrolyte) and molten metal batteries (take the idea of aluminium smelting and make it reversible).

All the non-battery alternatives I can think of work at industrial scale, so if you're looking for a household/small business solution, I think that at least for now batteries are it.

Comment: Re:Attempting with existing title was a mistake (Score 4, Funny) 239

by snowgirl (#49566523) Attached to: Valve Pulls the Plug On Paid Mods For Skyrim

If that was the case you would not have given them 25% and taken 75% for you and the game makers.

You know, I always hate how my grunt work for companies makes them 4 times the money they pay you. It's just greedy theft. We should start a movement where the means of production are owned by the workers rather than investors and management!

Comment: Re:Managers & HR take note (Score 5, Insightful) 124

by Michael Woodhams (#49557289) Attached to: When Exxon Wanted To Be a Personal Computing Revolutionary

There are three lessons here. One is about arbitrary work requirements, which you've made well.

Second is the problems which arise when vertical integration in your company means that one level's customers are another level's competitors. This conflict of interest is liable to drive away customers. (A company my father worked for many years ago had a similar issue: one branch manufactured and sold refrigeration equipments and spare parts. Another branch maintained and repaired refrigeration equipment, so their competition was the manufacturing branch's customers. The maintenance branch was separated into a new company to avoid this problem.)

Third is when you have a large corporation with an innovative product, that innovative product's potential can easily be crippled by being held hostage to vested interests of other parts of the corporation.

Comment: Re: How about basic security? (Score 5, Informative) 390

by jd (#49516499) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

IPSec is perfectly usable.

Telebit demonstrated transparent routing (ie: total invisibility of internal networks without loss of connectivity) in 1996.

IPv6 has a vastly simpler header, which means a vastly simpler stack. This means fewer defects, greater robustness and easier testing. It also means a much smaller stack, lower latency and fewer corner cases.

IPv6 is secure by design. IPv4 isn't secure and there is nothing you can design to make it so.

Comment: Re: Waiting for the killer app ... (Score 3, Informative) 390

by jd (#49516451) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

IPv6 would help both enormously. Lower latency on routing means faster responses.

IP Mobility means users can move between ISPs without posts breaking, losing responses to queries, losing hangout or other chat service connections, or having to continually re-authenticate.

Autoconfiguration means both can add servers just by switching the new machines on.

Because IPv4 has no native security, it's vulnerable to a much wider range of attacks and there's nothing the vendors can do about them.

Comment: Re: DNS without DHCP (Score 4, Informative) 390

by jd (#49516387) Attached to: Why the Journey To IPv6 Is Still the Road Less Traveled

Anycast tells you what services are on what IP. There are other service discovery protocols, but anycast was designed specifically for IPv6 bootstrapping. It's very simple. Multicast out a request for who runs a service, the machine with the service unicasts back that it does.

Dynamic DNS lets you tell the DNS server who lives at what IP.

IPv6 used to have other features - being able to move from one network to another without dropping a connection (and sometimes without dropping a packet), for example. Extended headers were actually used to add features to the protocol on-the-fly. Packet fragmentation was eliminated by having per-connection MTUs. All routing was hierarchical, requiring routers to examine at most three bytes. Encryption was mandated, ad-hoc unless otherwise specified. Between the ISPs, the NAT-is-all-you-need lobbyists and the NSA, most of the neat stuff got ripped out.

IPv6 still does far, far more than just add addresses and simplify routing (reducing latency and reducing the memory requirements of routers), but it has been watered down repeatedly by people with an active interest in everyone else being able to do less than them.

I say roll back the protocol definition to where the neat stuff existed and let the security agencies stew.

Comment: What is wrong with SCTP and DCCP? (Score 4, Interesting) 84

by jd (#49503031) Attached to: Google To Propose QUIC As IETF Standard

These are well-established, well-tested, well-designed protocols with no suspect commercial interests involved. QUIC solves nothing that hasn't already been solved.

If pseudo-open proprietary standards are de-rigour, then adopt the Scheduled Transfer Protocol and Delay Tolerant Protocol. Hell, bring back TUBA, SKIP and any other obscure protocol nobody is likely to use. It's not like anyone cares any more.

Make it myself? But I'm a physical organic chemist!