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The 100-Million Mile Network
mykepredko writes "eWeek has an article on the network and radio topography of the two Mars rovers and how they communicate with satellites in Mars' orbit as well as the Earth. The article ends by giving four rules for maintaining a space network, a) Automate processes, b) Bulletproof your gear, c) Be persistent and d) Simulate potential problems, which are probably good rules for any network."
NEVER! BUT NEVER! Install Windows unless you want openly relayed spam from space!
Even if I knew that tomorrow the world would go to pieces, I would still plant my apple tree. -Martin Luther
Never have a public webpage that can be linked to from Slashdot.
b) Bulletproof your gear
I'd think micrometeorite-proofing my gear would be more useful.
funny munging
I didn't RTFA, but it sounds like they're just running ethernet cables (or OC12 or whatever) to Mars. Didn't they stop to think that the planets move? Ridiculous! The ESA and NASA really need to get their acts together.
True story.
Replace 'spacecraft' with 'child'...
"The most difficult thing is to know how to talk to the spacecraft when you're getting no response from it," says Douglas J. Mudgway
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MWAN - Multi-World Area Network i guess....
Does anyone know which OS these things run? I heard that NASA really want 386 processors?
Does this mean they run on Windows? That must SUCK.
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b) Bulletproof your gear
For what? Those pesky Martians?
If only the Beagle 2 people had seen this article beforehand.
Persistantly empty clip after clip of rounds from an automatic rifle at your prototype. If it survives, begin production.
Persistency is not as important on an earth-bound LAN. Most of the time, bringing it back up is not an issue of "try, try again", but of just doing it right in the first place.
Online Starcraft RPG? At
Dietary fiber is like asynchronous IO-- Non-blocking!
...Starfleet can communicate over extremely long distances with out an lag. Apparently, the lag is encountered occasionally when it is necessary to fill plot holes. But otherwise, not at all. The laws governing subspace communication elude me.
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"The most difficult thing is to know how to talk to the spacecraft when you're getting no response from it," says Douglas J. Mudgway
no response as in ping timeout? dude, if your're ping'ing something on mars use ping -t infinity
What are the IP's for the Mars Rover? I have some Microsoft Mars Simulator (c) driving to do...
Just a few peices of bailin' war oughta do it...
e) submit your URL to /. and start up the benchmark server.
They are just perpetuating the myth that the rovers are really on mars. Everyone knows that it is all done in a Hollywood sound stage. The problem a few weeks ago with the the first rover was traced to someone using the mircowave oven and causing interference with their radios on the set. Anyone want another burrito heated up?
Here I thought they just had a reeeeeeally long cable.
Slashdot sucks
and I can't even get a cable/DSL modem yet!!! new slogan... Earth First, We'll Network the Other Planets Later
"The orbiter then uses its more-powerful antenna to send as many as one million bits of data per second back to Earth. While fairly fast for an attenuated radio connection, that's only about a tenth of the speed of a cable-modem connection for the average home-computer user." Unless they are using Commcast, such high bandwidth usage would violate the vauge acceptable use policy, putting the rover in the top 10% of Mars bandwidth users. Ah, maybe that's what happened. NASA ignored the first warning letter, and got cut off.
It appears that one of the direct results of NASA research will be better networks, both on Earth and elsewhere. Just about anything and everything applied to a deep space network can be applied right here at home. I'm also wondering about wireless network tech resulting from all of this.
The article seemed to fail to point out that these things are using OLD technologies... UFH? Jesus, that's been around for ages. Their basic data transmission seems to be just that... basic. . No bells and whistles. No wireless garbage. Not super fast. I see failures when people use cutting edge stuff. My business computers need to be ROCK SOLID. I don't use wireless. My hardware uses serial and parallel ports instead of USB/firewire/whatever. I use W2K as a platform. I use an external modem through a parallel port for important credit card stuff.
I use what has worked reliably for years and years. I'm not gonna risk my business being down because of some stupid gee-whiz technology that's only been out for a few years. Engineers that build solid, reliable, critical systems (financial, medical, avionics) do the same thing.
We can comunicate with a rover on the surface of Mars, but I still can't get broadband at my house. Well technically just about anyone could get satalite, but it is not adequite for games.
The orbiter then uses its more-powerful antenna to send as many as one million bits of data per second back to Earth. While fairly fast for an attenuated radio connection, that's only about a tenth of the speed of a cable-modem connection for the average home-computer user.
... did I miss something? My DSL line peaks at 1.5Mb on a good day. Where can I get a ten-megabit cable modem? And "average home-computer users" have them? I thought average home-computer users were still using 56K modems.
Uhhh
Oh, I get it now. According to this calendar, it's 2008. Damn, that was a nice nap. Need to catch up on the last four years of news. Hope something horrible happened to Microsoft.
What? SCOSoft? Oh, shit.
ZFS: because love is never having to say fsck
Considering how enthralled we are about seeing Mars up close and personal now, I'd think this would be a Really Good Idea.
This sig no verb.
I think that Spirit should be considered a big win for NASA. They patched a software bug on a platform that had corrupted flash, basically having to reinstall portions of operating code.
Something about the repairing a 747 while it is in flight analogy.
It may not be as dramatic as the rescue of Apollo 13, but they should be commended for well though out design principles, instead of just taking cheap shots at them when something fails as most people are wont to do.
Just wait till spam starts to relay from Mars
Them crafty spamers have spoofed every other network. Just wait till the IP trace routes through Mars.
Martian Viagra pills 25% off
Order now and save on shipping.
They've claimed that subspace communication travels at very close to the maximum warp possible (something like warp 9.999999), much faster than the ships, in part due to the fact it's pure energy, and in part due to amplifiers they place throughout the galaxy. This explains why when they're in less charted space, the signals sometimes take longer.
If someone did manage to DoS or somehow log in to the rover and damage the software it could be the most damaging single-target attack (dollar wise - at over $400 million per rover) of all time. I think that's kind of scary.
c) Be persistent
Do they really need that in the handbook? What did they use to do when they had a problem?
Engineer 1: "Shit Fred, I can't ping it."
Engineer 2: "Oh well, cest la vie. You wanna grab a beer?"
More info on communications between Mars/Earth and the DSN (Deep Space Network):
- NASA's MER2004 Communications with Earth Overview
- DSN (Deep Space Network) Main Page
- Wikipedia entry on Deep Space Network
--
For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.
Bulletproofing your gear is extremely important. The old IBM XT's were up for that, I took one camping once (just the case and CPU) and we set up it and took shot's at it with .22's. Only 1 shot pierced the 1/4 inch thick steel case, and the only actual damage done was a really noisy fan afterwards.
Think martians have more firepower then .22's, though? d'oh!
Mod +5 Drunk
To hell with bulletproofing, that's only useful on Earth. If they make it ASTEROID-PROOF... now THAT would be impressive.
Deep Space Network website:
http://deepspace.jpl.nasa.gov/dsn/
Not very detailed but a nice overview of the setup.
No.
I remember when legal used to mean lawful, now it means some kind of loophole. - Leo Kessler
or did they not talk much about space networking? I want to know what protocols they use, how data is buffered on the sats orbiting mars, etc. Where are the technical details?
Error: Id10t detected
Clearly, Mars Channel 25 caused the original Spirit communication breakdown by interrupting it with an episode of Days of our red, dreary lives.
As Murphy and others have pointed out, it's the flaw you don't test for that gets you every time. There are an infinite number of things that can go wrong, and a finite number of things you can test. The idea that you could somehow plan for every contingency is what stops many a promising project.
I am officially gone from
Rules for maintining a space network:
a) Automate processes
b) Bulletproof your gear
c) Be persistent
d) Simulate potential problems
e) Don't crash into the damn planet
f) Don't confuse feet and meters
g) Don't "misplace" quarter-billion dollar probes
h) Don't let probes explode because you left out the fuel-check valve
i) Don't press the big red shiny button (Narf!)
j) ???
k) PROFIT!
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- - You can't take something off the Internet! That's like trying to take pee out of a swimming pool.
Automate processes.
Encode many operations in a remote device, so it can solve its own problems.
Bulletproof your gear.
Refine systems under your direct control, like Deep Space Network antennas, to make sure they aren't the cause of an outage.
Be persistent.
Analyze any shred of communication. Build theories. Exploit small wins.
Simulate potential problems.
Test theories on duplicate devices, under your control, even if conditions aren't alike.
It's much easier to grab a beer than to spend a few more hours figuring out yet another theory on why the rover talking.
I notice that in some navigation images there appear to be gaps with empty or scrambled data. I wonder if this is communications problems, or perhaps other kinds of data that trumps image data temporarily.
Table-ized A.I.
b) Bulletproof your gear
Maybe if your running a network in an American high school?
This comment does not represent the views or opinions of the user.
I have to say, that's the first thing that popped into my head when I read the title. "Hundred million mile? MILE? Didn't they learn anything the last time?"
I was surprised to see no mention of Vint Cerf's InterPlaNetary Internet Project.
... out on shelves now!
Just think about how many cans of pringles those guys at NASA had to eat to get 100,000,000 miles out of their link.
Is it me, or does the media just assume that everyone just has an 8th grade education?
/.'ers feel the same way.
That's nice it transmits on "TV Frequencies 14 and up"...gimmie the good stuff, man, how does it *really* work. Quadrature PSK modulation? Multi-channel? Compression? Gain budgets?
No im not asking too much, I'll bet most
Thank you
-Dan N7NMD
I was wondering if NASA has actually disclosed the details of what they believe was the malfunction of the Spirit rover?
As someone who has developed backup and recovery systems for embedded systems using vxWorks and flash memory I have my own theory of what could have gone wrong.
There is an intermitant problem that can occur when using a combination of vxWorks 5.5, dosFs2 and flash memory.
The problem goes like this : When file A is written to flash memory formatted with a FAT16 table the FAT table is updated to say which disk clusters are occupied by file A, and hence no longer available as free disk space. So when file B starts writing to the hard disk it checks what clusters are free to write to.
Now a timing problem can occur when a process writing files in a sequential order closes the file handle to A and opens a new handle for B and starts writting to B. The problem exists because the clusters used by A have not been updated to the FAT in time before file B starts writing. The consequence of this is that some of the data belonging to A is overwritten hence breaking the chain. Once this has occurred the FAT and file A cluster chain are corrupt. Once this corruption occurs more corruptions occur with rate of corruption errors growing expotentially until the flash memory can longer function for disk I/O.
Now as the problem only occurs rarely it is very hard to reproduce in a lab. Also as the rate of corruption is expotential then catching the orginal culprit is even harder. I have spent weeks just trying to catch and diagnosis the problem before eventually catching it.
Unfortunately once the flash had started to become corrupt the only way to correct it was to reformat the flash memory.
As for solving the problem, before closing the handle of a file that had been written to flash memory was done an ioctl call would be made to the dosFs2 library to write the size of the file to the disk. Once this solution was is in place the problem never raised its head again.
There's a long testing cycle to get hardware certified for space operations.
Radiation hardening isn't the first thing Intel or AMD puts onto a bleeding-edge chip.
Missions are planned years in advance, often most of a decade.
Where I'm going with this is, even if they chose a barely-working new technology, it would be old by the time it got there.
Your point is well taken -- for example, composites have been around for decades, Boeing is still building planes out of aluminum, and it's because they're not going to put anything in a safety-critical part of a jetliner until all the surprises have been found and fixed.
Like CIO's and CEO's of big/medium businesses are going to start their own business plan to privately colonize Mars based on eWeek's article. I hate how eWeek always talks in jibberish lingo such as "processes", "exploit", "refine", "streamlined", etc. Also NASA can't even bulletproof their equipment, hense flash memory crashes. eWeek should have mentioned including triple redundancy.
Except:
What You Should Do To Run A Space Network
Automate processes.
Encode many operations in a remote device, so it can solve its own problems.
Bulletproof your gear.
Refine systems under your direct control, like Deep Space Network antennas, to make sure they aren't the cause of an outage.
Be persistent.
Analyze any shred of communication. Build theories. Exploit small wins.
Simulate potential problems.
Test theories on duplicate devices, under your control, even if conditions aren't alike.
First (from page 1) how many people get 10 Mb/s from their cable modem? Yikes. It looks like david_carr@ziffdavis.com needs to go back to school. There are numerous discrepancies in his report that do nothing than excite, hype, and distort what really happened. We don't need reporters like this, we need more scientists, engineers, and astronomers!!!!
from Hell?
There is a bit of M$ technology on the mars rover :-)
isn't there? The filesystem is FAT. Hang on a
minute, that what messed up with the first rover
wasn't it, so yes your point is valid, sorry
Think of all that money they have spent building 70M radio antennas and custom radio gear when it is so obvious all you need are off the shelf Wifi cards and a couple of Pringles Tins ;)
Philip
Signatures are broken