Forgot your password?
typodupeerror

Comment: Important work - gives handle on earth's dynamo (Score 4, Insightful) 80

by Cliff Stoll (#47298935) Attached to: Satellite Swarm Spots North Pole Drift

This is important work, which compliments terrestial geomagnetic measurements and space based observations.

The earth's magnetic field results from a planetary dynamo. Magnetic field lines get frozen into the electrically conductive fluid core. Then, differential motions in the fluid causes the magnetic field to get twisted up -- it's no longer is the simple dipole (like those bar magnets that you played with as a kid). Instead, the earth's magnetic field develops high order moments (sorta like bumps and dips). These shapes evolve as the conductive core moves. Eventually, the magnetic field gets so tangled up, that it unravels. At that time, the earth's field reverses. These magnetic field reversals show up in the geologic record ... every 10,000 to 100,000 years, there's a flipover.

Measurements like the ESA Swarm satellite give us a handle on the evoloution of the Earth's magnetic field, as well as showing how that field interacts with the magnetic and particle environment of the solar wind.

(disclaimer - most of what I just posted is from a terrific graduate class that I took at the Lunar & Planetary Labs way back in 1979, and when I worked with Charles Sonett, who studied the solar wind. Likely, much of this is way out of date!)

Comment: Re:Well, yes, I was there... (Score 1) 120

by Cliff Stoll (#47182183) Attached to: Whom Must You Trust?

And my thanks back to you, oh Anonymous Coward: The 15 cents in royalties from your purchase of m'book is now helping my kids attend college. Uh, it'll last about 1.3 minutes.

You say that you're managing firewalls - all sorts of possibilities! I had the honor of working with Van Jacobson at LBL when he first researched TCP/IP traffic jams and compression. I was amazed at how much could be done by looking at traffic and thinking about the interaction of traffic, buffers, routers, and network congestion. Wonderful stuff - what looks like a boring problem may be an opportunity for research.

With that in mind, here's my encouragement to you: Go and sharpen your tcpdump & wireshark tools. Figure out what's really happening to those packets. Who knows what you'll uncover?

Comment: Re:IF you are the REAL Cliff Stoll? (Score 1) 120

by Cliff Stoll (#47182047) Attached to: Whom Must You Trust?

(blush). Thanks!

Now it's your turn: Go forth and make our networked community friendlier, stronger, more trustworthy, and more useful.

Best wishes,
-Cliff

PS: Of course, you raise a fascinating, self-referential question. How can you tell if this posting is from the real Cliff Stoll? I know it's me - and it's easy to prove in person, but difficult online. For the best proof, well, stop by for coffee. Way more fun than posting online.

Comment: Well, yes, I was there... (Score 5, Interesting) 120

by Cliff Stoll (#47181593) Attached to: Whom Must You Trust?

It's been a quarter century since I chased down those hackers. Hard to think back that far: 2400 baud modems were rarities, BSD Unix was uncommon, and almost nobody had a pocket pager. As an astronomy postdoc (not a grad student), I ran a few Unix boxes at Lawrence Berkeley Labs. When the accounting system crashed, my reaction was curiosity: How come this isn't working? It's an attitude you get from physics -- when you don't understand something, it's a chance to do research. And oh, where it led...

Today, of course, everything's changed: Almost nobody has a pocket pager, 2400 baud modems are a rarity, and Berkeley Unix is, uh, uncommon. What started out as a weirdness hiding in our etc/passwd file has become a multi-billion dollar business. So many stories to tell ...

I've since tiptoed away from computer security; I now make Klein bottles and work alongside some amazing programmers at Newfield Wireless in Berkeley. Much fun debugging code and occasionally uncorking stories from when Unix was young.

Warm cheers to m'slashdot friends,
-Cliff

+ - Big Brother Blinded - Smog blocks Survelliance Cameras->

Submitted by Cliff Stoll
Cliff Stoll (242915) writes "Perils of dystopia: To the Chinese central government, the smog that blankets the country is not just a health hazard, it's a threat to national security.

Last month visibility in Harbin dropped to below three metres because of heavy smog. On days like these, no surveillance camera can see through the thick layers of particles, say scientists and engineers.

Existing technology, such as infrared imaging, can help cameras see through fog or smoke at a certain level, but the smog in some Chinese cities is a different story. The particles are so many and so solid, they block light almost as effectively as a brick wall."

Link to Original Source

Comment: Well thought out dissertation! (Score 3, Informative) 204

by Cliff Stoll (#45121789) Attached to: Billion Year Storage Media

Excellent thesis and a most delightful dedication!

    A few salient points from this thesis, for the Slashdot crowd:
    - Accumulation: knowing what to keep and what to toss
    - Distribution: where/how to keep copies
    - Digital stewardship: maintaining objects isn't enough ... you must properly catalog things
    - Long term access means more than just saving bits ... they must be properly rendered

Convolved on this are problems with copyright, fair use, payment for archives, orphaned collections...

Then there's the cost of creating and maintaining a long term digital repository.
Librarians have done a terrific job with our printed archives. Who will become our digital librarians?

Hardware

Bypassing US GPS Limits For Active Guided Rockets 126

Posted by timothy
from the use-for-good-not-for-evil dept.
Kristian von Bengtson writes with a link to a short guest post at Wired with an explanation of how his amateur rocket organization Copenhagen Suborbitals managed to obtain GPS receivers without U.S. military limits for getting accurate GPS information at altitude. Mostly, the answer is in recent relaxations of the rules themselves, but it was apparently still challenging to obtain non-limited GPS hardware. "I expect they only got the OK to create this software modification for us," von Bengston writes, "since we are clearly a peaceful organization with not sinister objectives – and also in a very limited number of units. Basically removing the limits is a matter of getting into the hardware changing the code or get the manufacturers to do it. Needless to say, diplomacy and trust is the key to unlock this."

Comment: Corn Grenade in 1989 (Score 1) 378

by Cliff Stoll (#44831221) Attached to: TSA Reminds You Not To Travel With Hand Grenades

Some 25 years ago, I was on booktour for Cuckoo's Egg. I visited Iowa City and spoke at Prairie Lights bookstore -- delightful people and a wonderful place! A haven for writers, readers, and hackers.

After my talk, I passed along a Klein bottle to an Iowa computer hacker who was fooling with unix. In turn, he gave me a Corn Grenade . I tossed it in my backpack, headed for my next stop, and next evening went to Ames Municipal Airport.

This was in pre-TSA days, but there was certainly airport security: the security guy at the Ames airport discovered the corn grenade in my carry on. Happily, he recognized what it was - a cool, brass, art sculpture which was completely inert. By that time into booktour, I was pretty inert. We chatted for a few minutes, and I took the commuter plane to Chicago.

I'd forgotten about my 3 pound brass friend when the plane landed at O'Hare. But the Chicago X-ray scanner found it, and all sorts of alarms went off. Natch, I was taken aside, given the third degree. Seems that corn grenades aren't recognized in the distant lands of northern Illinois. I had to explain all about corn grenades (and my book, and klein bottles...) Missed my flight, slept overnight in O'Hare, and wound up shipping the heavy lil' guy by UPS ground. Today, that brass ear of corn smiles at me from across my dining room, reminding me when I got hacked by a computer jock in Iowa City...

+ - Container ship breaks in two, sinks

Submitted by Cliff Stoll
Cliff Stoll (242915) writes "Along with 7000 containers, ship MOL Comfort broke in half in high seas in the Indian Ocean. The aft section floated for a week, then sank on June 27th. The forward section was towed most of the way to port, but burned and sank on July 10th. This post-panamax ship was 316 meters long and only 5 years old. With a typical value of $40,000 per container, this amounts to a quarter billion dollar loss. The cause is unknown, but may be structural or perhaps due to overfilled containers that are declared as underweight. Of course, the software used to calculate ship stability relies upon these incorrect physical parameters."

Comment: What's the meaning of the 2nd "T" in AT&T ? (Score 1) 205

by Cliff Stoll (#44019523) Attached to: India To Send World's Last Telegram

My first job was delivering telegrams (by bicycle) in downtown Buffalo during the 1960's.
My Western Union office had its hours posted on the door: "We Never Close". The building's been torn down, so, in a sense, the message turned out to be true.

Question: what'll happen to the American Telephone and Telegraph Corporation?

Here in Berkeley, one of the main drags is Telegraph Avenue and a cell-phone store is named "Telegraph Wireless"

Comment: Beauty of Math; Beauty of Computer Science (Score 4, Interesting) 656

by Cliff Stoll (#43877679) Attached to: Ask Slashdot: How Important Is Advanced Math In a CS Degree?

I work in computing; a meter away is a mathematician.

He knows real math: group theory, complex analysis, Lie algebras, topology, and, yes, differential equations. To him, math isn't about numbers ... it's about rigor, elegance, and beauty.

No surprise that his code is rigorous, elegant, and beautiful. When he showed me how to use Cheetah to build templates in Python, he explained things with an clarity and parsimony. In his world, clumsy coding is as bad as a clunky math; a clear mathematical proof is as fascinating as a tightly written function.

This man is the go-to guy for the 100 person business. Soft spoken and never argumentative, his advice and opinions carry weight. I'm honored to work alongside him; not a week goes by that I don't learn from him.

Comment: My Dad's 30 year old radio glowed in the dark (Score 2) 674

by Cliff Stoll (#36911404) Attached to: Why Your Dad's 30-Year-Old Stereo Sounds Better Than Yours

Sure - I remember my Dad's 30 year old radio, a Philco model 60 from 1936. Those thirty years were the the golden age of radio I caught just the tail end in the late1950's.

His cathedral radio glowed in the dark, thanks to 5 vacuum tubes and an incandescent dial lamp. Took a minute to warm up (boot?) thanks to the 6 volt filaments and sagging line voltage (the thing drew 60 watts just idling). Superhetrodyne tuning of the AM broadcast band gave it a response from perhaps 50 to 2000 Hz, give or take 10 db. Stereo? Naw it didn't even have FM (though you could tune in shortwave broadcasts from Moscow)

Fidelity? Well, the Lone Ranger theme came boomed in just fine, as did Jack Benny, Elvis, Carl Perkins, Jerry Lee Lewis, Buddy Holly, Ritchie Valens, and the Big Bopper. Nothing like staying up late to tune the latest releases from WKBW, CKLW, or WABCs Cousin Brucie. Or joining the Night People to catch Jean Shepherd on WOR after midnight.

I've heard plenty of music since then, on vinyl, cassette, 8-track, CD's and mp3 -- great stuff! But I miss the excitement of stalking the elusive Rock and Roll station...

"And do you think (fop that I am) that I could be the Scarlet Pumpernickel?" -- Looney Tunes, The Scarlet Pumpernickel (1950, Chuck Jones)

Working...