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Space

ICMP_HOST_BELOW_HORIZON - TCP/IP Into Orbit 150

Posted by Hemos from the packets-in-spaaacceee! dept.
Christopher Neufeld writes "As reported on ScienceDaily today, on April 10 of this year, some standard IP modules were uploaded to UoSAT-12, and got it answering pings. "
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ICMP_HOST_BELOW_HORIZON - TCP/IP Into Orbit More

ICMP_HOST_BELOW_HORIZON - TCP/IP Into Orbit

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  • Re:HUH? (Score:1)

    by Anonymous Coward
    Hi slashdot-terminal! Enjoying the AC account?

    Hehe.

    thank you

  • Great!!! (Score:1)

    by Anonymous Coward
    Now I can telnet to my refrigerator to change its orbit.

  • A Fire Upon The Deep (Score:1)

    by Anonymous Coward
    Awesome sci-fi epic by someone called something like Vernor Vinge.

    It has an interplanetary network on that scale, with huge inter-solarsystem gateways... ya know, the economies of a whole planet would stem from the fact it was a gateway... dman fascinating read, very recommended.

  • TCP/IP was developed in a time when ping times were on the order of 10000 ms from coast to coast with non-robust network paths, so it's not a huge surprise it works to a satellite.

    I wonder what UoSat-12's IP address is?


    ...phil

  • Re:Is the technology transferable to Iridium? (Score:3)

    by phil reed ( 626 ) on Wednesday May 03, 2000 @09:10AM (#1094150) Homepage
    Trip time to geosynch orbit is 23000/186000 = .12 seconds, so round trip transit time is about a quarter of a second. UoSAT12 isn't that high, so the trip time is shorter.

    The rest is left as an excercise for the reader.


    ...phil

  • "Comfort of home"? Pretending that I'm a $6/hour ISP admin, couldn't I trap those packets and crash a satellite?

    Let's say that the engineer has logged into the satellite via ssh. His connection is a little laggy, but nevertheless he's entering attitude-control commands for future execution. You're sniffing his packets, but what do you see? Noise, mostly. What could you do with it? Probably nothing.

  • Voyager weekly status raport [nasa.gov]

    According to that Voyager is about 75 AU from Sun.

  • Notice that the User has a period in the front.

    Hal Duston
    hald@sound.net
  • Except for the US scientists that work with nuclear weapons....;->
  • I'm refering to Gary Clail's early work; just wondering...
  • Hey, thanks for the link! I used to have a pretty good collection of Tackhead records, but they were swiped by a "friend" many years back. All I have left is the "alien cover" album sleeve... and for the life of me I can't find another copy in any record stores I've been trolling; it's pretty obscure stuff.

    I've got a good collection of old Cabaret Voltaire, Throbbing Gristle, Zoviet France, Controlled Bleeding, Negativland (including the wallpaper sample album!), Nocturnal Emissions, Psychic TV, among others (oh wow I just found a Tackhead "Whats your mussion now?" EP... cool!). This stuff is just itching to get converted to mp3 -- I don't consider that so much a copyright violation as preserving history. Oh well, feel free to email me if you'd like to discuss this further.
  • As much as I respect this as a really, really cool hack (installing IP software alongside the old stuff is a pretty nifty trick) you really have to wonder if this is a great idea. No matter how much security they put in, this makes either the satellite or their router vulnerable to a lot of the stuff people pull with TCP/IP these days. I have to think that maybe a completely private TCP/IP based intranet (as opposed to the "engineer logging in from home" image the article presents) is probably the only way that they could make this secure.
    OTOH, the idea of DOSing a TV sat is pretty cool :)
    ~luge

  • Bring On The Packet Monkeys.... (Score:4)

    by Uruk ( 4907 ) on Wednesday May 03, 2000 @08:54AM (#1094158)
    Slashdot will have that thing DOS'd out of the sky by this evening, I'm sure.

  • The real question becomes: "How do we extend internet protocols to handle ping latencies ranging anywhere from seconds to centuries?" The new protocols should have redundant transmissions and *very* large buffer caches. Timeouts shouldn't occur until some multiple of the latency has passed.

    How about this, if the objective is Earth<->Mars, you have several artifical sats that orbit the sun. You route through these sats using a potocol _LIKE_ BGP routing. You may even be able to make the routing protocol smart enough to know its position in space and select the best next hop. By breaking the trip down into smaller hops, data integrity can be checked at each hop.
  • As far as I was aware, some (if not quite a bit of) internet traffic is already routed through sattelites as with telephone calls. Okay, so now you got the actual computer in space, but this is nothing groundbreaking.
    I mean, just think of all the extra NASA missions: STS-31337 - Astronauts launch to press reset button on blue-screened sattelite!

    And for the script kiddies, the IP is 207.46.130.14. (The intelligent among you will realise that this is merely an elaborate plot to packet/slashdot the evil empires (aka M$) website. :P)
  • I remember seeing somewhere that people were working on a Deep space protocol, a successor to TCP/IP that didnt need acknowledgements for every packet and avoiding the timeout problems.

    The problem with thinking about internet in space is that we are going to need people at the other end, and unless there is a colony on mars, then there is no point in placing an internet link to one or two probes.

    The same goes for interstellar networks, if (when) we advance far enough to colonise other solar systems, we will most likely have discovered a method to send signals faster than light (as well as Superluminal velocities in spacecraft). If not, and radio signals are our only method of communicating via computers, then it would work out far faster simply jumping in one of our little spceships and delivering the message by hand.

    Thing is, when we get to the stage of travelling interstellar distances, we can just ask bug-eyed-bill and his space poodle how their species did it! (Assuming M$ and government philosophy of what they dont know, assume they are to stupid to know, and charge them for the priveledge, didnt take them over that is)
  • I'll take down this puppy yet. Me and a few Palm VIIs should be enough to run a nice DDOS attack...

    <rubbing hands together evilly>

    ;)
  • Let's say that the engineer has logged into the satellite via ssh. His connection is a little laggy, but nevertheless he's entering attitude-control commands for future execution. You're sniffing his packets, but what do you see? Noise, mostly. What could you do with it? Probably nothing.

    I guess we could go back and forth over this forever, but what about something on their machine? You know -- get a friend of his daughter's to install a poisoned version of ICQ that traps keystrokes. I think the problem isn't so much TCP/IP, but it's that this can be accessed from non-secure locations. IMHO, satellites ought to be adjustable only from steel-clad bunkers thousands of feet beneath the earth.

    OK, well maybe not that extreme. But you know what I mean.

    -Waldo
  • This is cool and all, but, all jokes aside, isn't this a security nightmare. Sure, you can put up a firewall, password proection, IP filtering, PGP, etc., but is that really enough?

    From the article:
    From the comfort of home, an engineer logs onto the Internet using a laptop computer and communicates with an orbiting spacecraft. Using industry standard Internet protocols, simple keystrokes send commands adjusting the spacecraft's attitude.

    "Comfort of home&quot? Pretending that I'm a $6/hour ISP admin, couldn't I trap those packets and crash a satellite?

    I'm not trying to be a fearmonger, but I really do think that this is a case of Too Much Stuff Connected To The Internet. We all laughed a few years ago when kooks started saying that "Internet hackers" could shut down power plants and kill small woodlands animals. At the time, of course, none of these things were net connected.

    Now, between IPv6-addressable squirrels and this satellite, we really could have a problem on our hands.

    -Waldo
  • There are some comments about this in the Linux kernel... see net/ipv4/tcp_timer.c:
    * [...] Note that 120 sec is
    * defined in the protocol as the maximum possible RTT. I guess
    * we'll have to use something other than TCP to talk to the
    * University of Mars.
    *
    * PAWS allows us longer timeouts and large windows, so once
    * implemented ftp to mars will work nicely. We will have to fix
    * the 120 second clamps though!

  • hmm... (Score:1)

    by Phexro ( 9814 )
    well, the website is hosted at goddard space flight center, which has the 128.183.0.0/16 network. assuming that it's not blocked (which it most certainly is) and is in the same subnet (somewhat likely), someone with some time, bandwitdh and nmap could just scan through the /16, logging all the high-latency links along the way.

    could be interesting. :)

    --

  • Mission operations, such as tracking, telemetry and command, are on a private Internet. You can't get there from here.

  • Re:How about some Amateur Sats? (Score:3)

    by Detritus ( 11846 ) on Wednesday May 03, 2000 @11:38AM (#1094168) Homepage
    Hard drives contain air at normal atmospheric pressure, not a vacuum. Most of them are not completely sealed, there is a small air filter that allows for pressure equalization. You would need to mount the hard drive inside a pressurized container on the spacecraft.

  • How about some Amateur Sats? (Score:3)

    by cvoid ( 13211 ) on Wednesday May 03, 2000 @08:49AM (#1094169) Homepage
    so, now that this has been done, how long until some of the amateur sats in orbit have this capability? with the launch of phase-3d, with its reprogrammable modems and modules, maybe we will have something to play with.

    i am actually suprised this wasn't done earlier with amateur satellites, as it is (aside from the issues involving communication with orbiting communications systems) just a wireless network connect. if the satellite was in polar orbit you'd have availability problems, but a sat in the clarke belt would be nifty.

    anyone know of plans in the amateur community to do this?

    oh, and check out AmSat [amsat.org] for info on amateur satellites and whatnot.

  • Oh spare me. There's obvious precautions and carelessness. Try asking JPL how NASA communicates with any of their space probes. What frequency, packet transfer protocol, etc. and they won't tell you. I know this first hand. We're not talking about a laptop being stolen or an unknown linux box plugged into a wall at los alamos, we're talking about a satelite of which hundreds of people are involved with. They are very, VERY careful from a controlling perspective, with good reason.
  • I think scientists are mostlikely smart enough to sit the thing on a private network behind a firewall ;)

  • Relax! Just swap out the comms controller with one running an adequate processor. Now grab OpenBSD load it up and you are there! Ultra Security is that simple.
  • Apple in 1979 released DOS 3.2 soon to be followed by DOS 3.3 in 1980.
    This was the operatingsystem Apple used on the Apple ][(+) with the 140 K 5.25 inch drives.
    In 1983 Apple released ProDOS which supported things like subdirectory's and hard drives.
    This was before the Mac and HFS (the first Mac uses MFS which didn't supported real subdirectory's).
  • So, do we get a .orbit top-level domain now? (And just how cool would that be?)

    satellite-13.iridium.orbit not responding still trying

  • Is the technology transferable to Iridium? (Score:3)

    by Andy Cole ( 17689 ) on Wednesday May 03, 2000 @08:45AM (#1094175)
    This story is good news for the Save Iridium project. If the technology can be transferred to run on the Iridium satellites they could be used to enhance the internet backbone. Any idea what the ping is to a satellite from earth? AFAICT it will be in the 1 to 2 seconds range, which isn't terribly ideal but would suffice for large downloads with large packet sizes, making the ping time have little effect.

    Just my 2c.
  • Actually, after a thorough study of alien communication protocols and network topologies, I have determined that this is not likely. Their computing systems are based on ternary numbering (their equivalent to bytes, which they call munches, are 9 ternary integers, or tits, wide). Furthermore, they have not developed star based network topologies - all of their systems connect using token ring topologies. Also, they are more advanced than us in certain areas: they never developed stupid connectionless protocols like UDP - they always had sockets and streams. Go figure.
    With the tits and everything, it is doubtful they will send a virus that is even executable on whatever processor is in there. We're safe for now.
  • when Napster was loaded onto it and a Metallica song uploaded. This is confirmed to be the highest upload recorded. The spacecraft has no comment at this time

  • You would need to mount the hard drive inside a pressurized container on the spacecraft.

    Actually, you would need to mount two disks, back-to-back, otherwise, when the drives spin up, the whole satilite will start rotating in the other direction. Newton's Third Law makes working in space a pain in the butt at times. :-)

    When I was working at the Space Science Center at Unnamed U., they were building instruments for data collection. They found it cheaper in the long run to simply use hundreds of megabytes of static RAM (what we computer geeks call "cache RAM"). RAM because disks are a pain to work with in space, and static RAM because it resists radiation better and doesn't need to be refreshed.

    I wonder what 192 MB of cache RAM goes for?
  • The sentence "What seems like science fiction" made me think that this "from home" situation was just an example in the article, and wasn't really what the NASA was doing.

    Egoine
  • TCP/IP was developed in a time when ping times were on the order of 10000 ms from coast to coast with non-robust network paths, so it's not a huge surprise it works to a satellite.

    Actually, these Plotted Results [nasa.gov] from the project's site shows us that ping times are between 0.1 and 0.2 seconds, a few of them higher. I've seen worse ping times on today's earth-Internet :)

  • Actually that's just a forged packet.

    A Martian packet is one that appears to have made a round trip to Mars (i.e. is older than the TCP 120 second timeout) en route to your computer.

  • ~/linux/net/ipv4$ grep martian *
    devinet.c: {NET_IPV4_CONF_LOG_MARTIANS, "log_martians",
    devinet.c: &ipv4_devconf.log_martians, sizeof(int), 0644, NULL,
    route.c: /* Check for the most weird martians, which can be not detected
    route.c: goto martian_source;
    route.c: goto martian_source;
    route.c: goto martian_destination;
    route.c: goto martian_source;
    route.c: goto martian_destination;
    route.c: goto martian_source;
    route.c: goto martian_source;
    route.c: * Do not cache martian addresses: they should be logged (RFC1812)
    route.c:martian_destination:
    route.c: printk(KERN_WARNING "martian destination %08x from %08x, dev %s\n", daddr, saddr, dev->name);
    route.c:martian_source:
    route.c: * RFC1812 recommenadtion, if source is martian,
    route.c: printk(KERN_WARNING "martian source %08x for %08x, dev %s\n", saddr, daddr, dev->name);

    (yes, I am kidding, and yes, that grep will actually print out what I posted)
  • We have been using linux, a direcpc dish and MSAT (mobile satellite) phones for about 2 years now in several locations. http://knet.on.ca/poplartrip/photogall2.html Ping times are about 1700ms. The system is painfully slow awaiting responses but fairly quick for downloads. Considering there was no access to begin with and in some communities no telephones this is a blessing for those who now use email to communicate and are able to do ICQ and such things.

  • This will make Vint Happy (Score:5)

    by David A. Madore ( 30444 ) on Wednesday May 03, 2000 @08:48AM (#1094184) Homepage

    Vinton Cerf (the "father" of the Internet, perhaps even without the quotes) is constantly talking about Internet in space, interplanetary Internet and so on. For example, in his celebrated essay (an Internet draft) "The Internet is for Everyone" (now the official motto of the ISOC [isoc.org]), he writes:

    "The Internet is moving off the planet. Already, an interplanetary Internet is part of the NASA Mars mission program now under way at the Jet Propulsion Laboratory. By 2008 we should have a well-functioning Earth-Mars network that serves as the nascent backbone of an interplanetary system of Internets: InterPlaNet is a network of Internets. Ultimately, we will have interplanetary Internet relays in polar solar orbit so that such relays can see most of the planets and their interplanetary gateways for most if not all of the time."

    To be quite honest, if I didn't have so much admiration for him, I would say that Vint is going just a bit off his rocker, there. But, who cares? The idea is fun, and if a man can't dream, what's left for him to do?

    Did you know it, the ISOC has even formed an "Interplanetary International Special Interest Group" (IPNSIG).

    --
    David A. Madore (ISOC member)

  • With all of the amateur satellites up in the air, a TCP/IP link, for all its worth, would be of some good use for rural areas. Although the current satellites do not possess this capability, future ones may be able to form a bit of a global network of users that could communicate to each other, albeit slowly. This would be a big improvement from the current digital routing that the satellite only does between users of the same satellite. (at about 9600 baud)

    I just hope that it is not made into another Iridium-like network. The reason the current satellites are not too busy right now is the need for an amateur radio license and the skills needed involved to track a low-orbit satellite. If TCP/IP is used for this purpose in the future, don't expect to have it on your cell phone or anything.

    Visit Amsat [amsat.org] if you want more information about the current state of amateur radio in the sky.

  • A hard drives heads are shaped so that they 'fly' over the surface. In other words, in order to actually have a relieable spacing of the heads above the platter, they utilise the Bernoulli efect (you know, same thing that keeps aircraft up). There is something of the order of 100 air 'molecules' between the head and the platter. It's spaced that much to allow for variation in head head (if you knocked it and caused a head crash, you wouldn't be impressed, would you?).

    I do recall that someone (Western Digital?) a few years ago (about 7 or so) reported on filling a harddrive with a liquid, that is more viscous than air. This allowed the head to platter spacing to be reduced, as the more visquius liquid is a better shock adsorber. I belive they had a working prototype at one molecule above the surface. Advantage of this is that it allow more precise control of applied force, and better spatial location of magnetic domainms (IOW - higher data density)

  • Nah. (Score:3)

    by hey! ( 33014 ) on Wednesday May 03, 2000 @10:27AM (#1094187) Homepage Journal
    "Comfort of home"? Pretending that I'm a $6/hour ISP admin, couldn't I trap those packets and crash a satellite?

    That's why things https and ssh exist. If I were a $6/hour ISP admin and could crack those, I wouldn't be a $6/hours ISP admin for long. There's tons of RSA encrypted traffic that's way more juicy.

    Combine VPN, strong encryption, and vigilant system administration and I don't think anyone will be sending spurious orders. Other than that I would see potential DOS problems, especially if the engineer is sending a sequence low level maneuvering orders that could be interrupted during execution. However you'd have to be brain damaged to design the system to work that way anyway -- what if your transmitter failed?

  • SETI (Score:1)

    by goten ( 36521 )
    Ok.. now who is going to port Seti@home to run on it? Kinda ironic don't ya think?

  • PINGS....IN....SPACE (Score:4)

    by yoshi ( 38533 ) on Wednesday May 03, 2000 @08:47AM (#1094189)
    Sorry, I had to do this. Puns are way too much fun.

    On a more serious note, this bodes well for network engineers who want to get into the satcom industry. The differences between the computer industry and the communications industry are rapidly disappearing.

    -Josh

  • The trick is to implement an addressing system that's extensible. If we over-implenent, like an addressing system with 128 64-bit fields we'll be wasting space now, for a while we will be ok (for a really long while) but then, with the unevitable expantion of computers, we will run out of space. If we implenet an extensible system from the start... all we have to do is drop in new support, and near-transparent upgrades to the system.

  • So what do we call it? The OuterNet?
  • The hard drive heads use air to keep from touching the disk. A hd in space needs some air.

    There are also problems with heat transfer because of no air. Cooling in space is not an easy thing to do.
  • Let's face it. It's highly likely that eventually, we're going to go forth and spread throughout the cosmos. Let's assume for a second that we don't discover ways to transmit data faster than the speed of light. How well will the Internet scale when it extends to distant planets or even stars?
  • Contrary to some people's beliefs, "DOS" never stood for "Disk Operating System". There was a popular PC operating system called "DOS" (now renamed "Windows"), but the name still meant "Denial Of Service", as anyone who used it knows.
  • OTOH, the idea of DOSing a TV sat is pretty cool :)

    "Kill Your TV"...and everyone else's, too, at the same time! :-)

  • Comment removed based on user account deletion
  • This isn't exactly as ground-breaking as one might be lead to believe. What it allows for is native-protocol communication between the Internet and other satellites. Crackers have "taken over" satellites in the past, so the thought is nothing new. And satellites are used in communication systems quite frequently. But now the satellites get their own IP address and can make use of native TCP/IP functionality, so it can only enhance telecommunications.
  • Let's face it. It's highly likely that eventually, we're going to go forth and spread throughout the cosmos. Let's assume for a second that we don't discover ways to transmit data faster than the speed of light. How well will the Internet scale when it extends to distant planets or even stars?


    Vernor Vinge already covered that in his two books "A Fire Upon The Deep" and "A Deepness In The Sky". Granted, the protocols being used are not IP, but the basic technologies, etc. are clearly (and at one point, explicitly) descended from modern-day networking.

    Vinge does better than most SF authors about having believable (from a tech and programming standpoint) computer systems. It is clear from his writing that he has thought about such things as "how would robust communications protocols work among civilisations that are spread out to interstellar distances and relativistic velocities" -- and his solutions are more than just handwaving. Of course, Vinge's day job is a CS professor...

  • I remember hearing about a new TLD, ".orb", for things in orbit. At the time, it was "shuttle.orb" for communicating with STS missions.
  • If you want some geniune spaced bits, just do a traceroute to mcmsun5.mcmurdo.gov. It goes through a geosynchonous sat along the way, and your bits will pick up lots of frequent flier miles.
  • Maynard: What's my mission now? Now what? Now to get a good line-out signal from my hacked I-opener, plug in a 30G hard drive, and change the boot logo from Tux the Penguin to a scan of the Nostromo's self-destruct panel from the movie "Alien"... In other words, yes, I was wondering when someone would spot the reference :)

    ObTack:
    This Tackhead [nl.net] site has pretty up-to-date info. And some really interesting links. Nuff said :)

  • Mmmmm, don't tempt me :)

    Seriously, I've been trolling for vinyl too. Very hard to find. All I have is the more recent stuff on CD. I'm regularly polling a couple of good indie record stores that have good industrial coverage and will let you know if I find anything rare. Meanwhile, keep your eyes on the obvious site that you've probably found from the Tackhead site I mentioned. (It was news to me too :)

    As for Tackhead - I'll heartily recommend the three "Power, Inc." volumes, which should still be available on CD. They're also being done through Keith LeBlanc's own label, which I would hope means that Keith actually gets some of the proceeds from the sales...

    (...getting back on topic, at least marginally...) ...unlike certain other bands which don't want their music *traded* as a commodity, but being bought and sold as a commodity is just fine. *g*

  • Re:How about some Amateur Sats? (Score:5)

    by Tackhead ( 54550 ) on Wednesday May 03, 2000 @09:25AM (#1094203)
    And of course, I'm surprised nobody has suggested the obvious application:

    Get Gold & Appel (or some similar organization) to launch a mess of "sats" into "orbit" at the Earth/Sun Lagrange points. Run something like "Freedom" on them. Give each sat a bunch of space-hardened (i.e. you need an atmosphere and some radiation and heat shielding) umpteen gigabyte RAID drives.

    15 minute ping times, sure. But how the fsck will RIAA stop us from downloading MP3s when the servers are located in deep space? :) :) :)

    All it takes is one .com billionaire with a really twisted sense of humor.

  • Slashdot will have that thing DOS'd out of the sky by this evening, I'm sure.

    Hmmmm....

    Maybe that can explain this [yahoo.com]

  • Guess you can't call them globally unique idenitifiers anymore.
    Sorry, I've been waiting to make that crack for a looooong time.
  • But what about when the sshd daemon dies, or stops responding to connection attempts and goes bananas, taking over all the satellite's processor time (ok, raises its load average to 1)?
    How does the engineer log in then? Thumb a ride on the next space shuttle?
  • Perhaps it should be .earth
  • MS is way ahead of you -- some of their docs refer to them as UUIDs (Universally Unique IDentifiers).

    I guess that Bill Gates, having achieved world domination (or close to it), decided to set his sights a bit higher...

  • standard Internet software modules were uploaded to the spacecraft.

    Brings new meaning to the term "upload".

    -Michael

  • If I read the article correctly, the door isn't open as far as many of the posted comments would make it appear.

    They've enabled ICMP. They've talked about controlling orbital adjustments. I'm not up on how these birds are built, but I'm not sure from what I've read that this in any way opens up the data stream to the Internet.

    Sure, you might be able to (literally) crash the satellite, but the idea of a DoS attack interrupting the data stream seems a bit of a reach. These are good examples of the problems which will need to be solved before our satellites all become nothing but nodes, but if someone managed a DoS attack on the IP port, it would only appear to mean they'd have to go back to inband satellite control instead of IP-based satellite control.

    But I suppose it IS logical to assume that all the satellite functions would eventually be exposed via IP. IF that were the case with Iridium, it would be ironic to see a hacker deorbit all the birds, then let Motorola file an insurance claim and finally turn a profit on the system!
    1. ... travel faster than light under certain circumstances
    Actually, there have been theoretical methods for doing just this from the quantum phyisics guys -- a process of quantum entanglement. The problem is (among many others) moving entangled particles farther than a few AU's apart. [Then again, someone or something would have to carry the other part of the "transceiver" to the other side of the cosmos...]

    I don't think IP is the best solution for long range, high delay and loss transmissions. Do you actually think NASA sends just one "turn left .015 degrees" command to a probe and wait for it to say OK? I would submit that there is a redundant, serialized stream of commands sent to the remote device which it then reconstructs the commands and sequencing to carry out it's task(s). [See also: Contact [imdb.com]] UDP is certainly capable of such messaging, but, well, UDP isn't a data stream.

    We'll see... there are people much smarter than the average /.'er playing with these sorts of things -- they aren't likely to talk about it tho'.
  • That won't work either if the hop is 4.3 light-years away. The standard TCP method is to hold a copy of the packet for retransmission until you know conclusively that it is no longer needed. In the case of USENET, articles can and do expire from the local disk storage before they can be transmitted to the next hop -- there are several "corrective" mechanisms for handling such overloaded feeds...

    The next thing ya' know, the universe will filled with drone arms [scifi.com]...

  • Im^H'm in but thel ag is horrribl^H^H^H^Hible (Score:5)

    by SIGINT ( 70588 ) on Wednesday May 03, 2000 @09:20AM (#1094213)
    w^HWell i finally got a shee^Hll on the satellite, but thhe lag is so bad i can'''t ^H^H^H^H''^Ht even use lynx well. Man, and theres something wrong with they^Hir stty settings. Anyway, FIRSTT POST FROM SPP^HACE! :wq^H^H^H oh yeah, i'm not in vii^H
  • Packing a TCP/IP stack into one of the Voyagers would be tougher than a PIC! And of what use would it be? You'd have to ping it before you went to bed to see the result in the morning, and 90% of your packets would be lost!
  • Into which jursdiction would the lawsuit fall??

  • that was the lamest movie Brent Spiner was ever in...
  • There is a rather large difference between connecting "through" a satelite and connecting "to" a satelite. You are basically getting data that is transfered through a satelite. The satelite acts as a mirror or a peice of UTP cable, just providing a means for the data to get to you.

    What the article is talking about is different. The satelite is actually part of the network and not just a transfer medium. They are talking "to" it. A paragraph in the article points this out:

    Commercial communication service providers have implemented the Internet using communications satellites for more than two decades, but the satellites did not have their own Internet address and could not recognize Internet messages. The UoSAT-12 became the first orbiting spacecraft to use only standard Internet protocols and technologies for end-to-end communications.


    Satelites have never really been used in this way before and I'm interested in it. It has the potential to speed up intercontinental communication quite a bit. I would think that it is a lot faster to bounce a signal through the air to a satelite to another satelite and then back to land on the other side of the planet than it is to pass the signal under the ocean via copper or fiber. Fiber is a faster medium for transfer but the routers and things slow it down.

    On another note, it would be a lot of fun to play with this. Anyone want to upload the source for DeCSS to an orbiting satalite?

    -magicsloth
  • Earth is 93 million miles from Sol; that's about 500 light-seconds. Jupiter, 5.2 AU or 2600 light-seconds; less than 45 minutes. Pluto is what, 40 AU more or less? 20,000 seconds, or about 5.5 light-hours. You'd have to be over 80 AU from Sol before your round-trip time reached a day. I remember when Usenet posts could easily take a day or more to propogate around the various servers; somehow, I don't think that the time delay would keep electronic culture from flowering across an enormous expanse of space.
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  • How well will the Internet scale when it extends to distant planets or even stars?
    How are you going to handle a retry request from a site 4.3 light-years away?

    TCP/IP essentially doesn't work over such distances. On the other hand, schemes like Fidonet and Usenet News would work fine as long as they had a transport scheme underneath. You can forget a System-Wide Web, but a system of caching servers for Usenet posts, static web pages, or any other kind of content that doesn't require active communication with the originator will work fine. All you have to do is broadcast everything that's new or changed, and use appropriate encoding to guarantee that the receiver can reconstruct any data errors (something like trellis encoding would be appropriate). What you'd get at Pluto would be some hours out of date and Alpha Centauri would be years behind the fashions, but it would get there.
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  • That's not the weak point. (Score:3)

    by Tau Zero ( 75868 ) on Wednesday May 03, 2000 @10:12AM (#1094220) Journal
    ...you really have to wonder if this is a great idea. No matter how much security they put in, this makes either the satellite or their router vulnerable to a lot of the stuff people pull with TCP/IP these days.
    There are basically 2 ways to talk to the spacecraft: through your own radio gear, or through whatever gateways and firewalls other people have put between the Internet and their radio gear.

    If you have your own radio gear, you could have sent commands to the satellite using whatever protocol and authentication it wants even without TCP/IP. Adding TCP/IP, if the satellite functions are protected with the same authentication codes, doesn't make it significantly easier.

    The other way is to hack through someone else's gateway. If they've firewalled it, you've got the problem of defeating the firewall before you get to the satellite and its authentication mechanisms. Of course, if someone has left the authentication info lying around in an accessible place on their Internet-accessible computer, you're all set... assuming the satellite will accept configuration commands over the TCP/IP channel (it might not, the article didn't say if this was only used for the store/forward system or command and control as well).

    It's a pity we can't just ask Bruce Schnier for his opinion of their security model.
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  • You'll have to ping farther than that. (Score:5)

    by Tau Zero ( 75868 ) on Wednesday May 03, 2000 @10:00AM (#1094221) Journal
    just something so cool about sending packets into outerspace and getting a response
    Space scientists would disagree with you on that point. This satellite is in low-earth orbit (LEO), which is not technically considered to be "outer space". If you uploaded a TCP/IP stack to one of the Voyager probes or even Galileo, that would certainly qualify. How many million msec is your timeout again?
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  • bet that last hop close to timing out!
  • Iridium birds are hard wire to do only one thing - hence that is why nobody bought the company to bail them out of bankrupcy. They cant be fixed, or upgraded very much (sure, I would imagine there are some minro firmware updates...) To accomodate these short comings, there were always a few extra sats in higher orbit that could be moved into place in take over in case of failure.
  • uh.. I would think that a VPN solution would be in place. I kinda think its implied. Lots of companies are passing trade secrets across VPNs and they have proved pretty secure thus far. just add a little encryption and youre all set.

  • Re:Is the technology transferable to Iridium? (Score:3)

    by 2sheds ( 78194 ) on Wednesday May 03, 2000 @08:59AM (#1094225) Journal
    Sadly a lot of the harware in Iridium is specifically desgined for switching voice comms - ICO however were able to re-design their sats due to the fact that they haven't got any into orbit yet...

    j.
  • Linux... Of course, since a BSOD at 600 ft could ruin your day

    I am part of a team that is operating an Apache Linux based webserver at 600 feet. The vehicle is unmanned and thats why reliability is paramount. Topside Communication is via a fiber optic cable.

    The Linux box is host to a data acquisition system that acquires vehicle health data and provides a human interface to control power. A Perl based application communicates to data acquisition modules (check www.Opto22.com) using a firewire driver rewritten from C++ to Perl.

    The operator interface is CGI/Perl and if a condition alarms occurs and is not acknowledged the application sends out e-mails alerts. The operator can view historical data which is plotted with Gnuplot which I can do at home in my underware.

    The entire system is 100% Open Source software.
  • correct me if I am wrong but I would imagine that the engeniers would have left something along the lines of a air gap for security on this sat considering that from what I read they are using this just to test the feasability of this concept



    or I am way off :-)

    Jon
  • Even if we have near light speed vehicles, radio waves are still faster. Barring communication via quantum entanglement (which seems fairly unlikely), the speed of light will likely be the limiting factor in social homogeneity once we start spreading out. This isn't entirely a bad thing, though. We're already too homogenized now, in my opinion.
  • ... (MSL) is defined in RFC793 as "2 Minutes", so with current electromagnetical communication methods the maximal diameter of a TCP/IP network like the internet is 2 light minutes wich doesn't even reach the next planet.

    (Sorry, I'm too lazy to check what difference TCPv6 makes here (if at all).)
  • I don't see how causing satellites to drop from the sky and crush squirrels is a problem. I mean, sure, if they use the satellites to crush OTHER things, that might be bad, but there are so many squirrels around here it would be like hitting the broad side of a... squirrel.

  • Maybe I'm showing my age here, but does anyone else remember "Packets from Mars"?

    martian: n. A packet sent on a TCP/IP network with a source address of the test loopback interface [127.0.0.1]. This means that it will come back labeled with a source address that is clearly not of this earth. "The domain server is getting lots of packets from Mars. Does that gateway have a martian filter?" Compare Christmas tree packet, Godzillagram.

    jargon/m/martian.html [science.uva.nl]
    From The Jargon file (4.2)

  • With the tits and everything, it is doubtful they will send a virus that is even executable on whatever processor is in there. We're safe for now.

    You've forgotten about Java - write once (on alien mothership), run everywhere (once the worm hits our Net). ;-)

    James.
  • Tell me about it. Much of our unmanned space program is inextricably linked with internet access. When I worked for the SOHO [nasa.gov] project at NASA/GSFC, several of the internal computers were cracked. Among them was mine -- a science workstation that could've (at the time) been used as a staging area for a more concerted attack on the command computers themselves (thanks to trusted-host protocols). The attackers used a well-known but unpatched hole in IRIX 6.2 (by default, the line printer account had no password). They were content to fire up an IRC server and brag about how kew1 they were -- we were lucky it was a random heist.

    Some of the other instruments' actual command computers were compromised in similar ways at other times. If the attackers had known what they were doing, (I think they, too, were script kiddies) they could've sent commands to the spacecraft, a million miles away.

    The problem for that project, as for so many, is lack of clear forethought about security and time pressure once the system was installed. We had a heterogeneous network set up by people from something like 10 different countries, and many workstations (mine included) that were administered by the scientists who used them.

    The big shock for me, both in my experience at NASA and at other high-technology, high-risk ventures, is that people remain people even if they work for NASA. Folks who are interested in flying spacecraft have little time to install the latest OS patches or to design secure protocols -- they're too busy shooting from the hip, making huge volumes of hastily written code work right, or cranking out the next research paper.

    IMHO, we need *less* connectivity, not more, to our spacecraft and their ground systems!

  • ...Is not advanced antisat missiles, but scr1pt k1dd13s with airforce commissions...

    'The Chinese tanks are advancing on our position sir!' '"ping -F north-hem.GPS" soldier!'
    Tyranny = Government choosing how much power to give the people.

  • OMNI (Score:2)

    by cara ( 118378 )
    The project doing this is OMNI [nasa.gov] (Operating Missions as Nodes on the Internet). Check out their web page [nasa.gov], it sounds like a cool project.

    This is definitely the way to go IMO. It will allow easier access to satellites or whatever in space and when this kind of thing becomes more common, the general public will be able to perhaps interact with satellites over the internet from their own computer.

  • Now the satellite is going to get slashdotted, and the whole thing is going to come crashing down on our heads.

  • Security in space. (Score:3)

    by ClayJar ( 126217 ) on Wednesday May 03, 2000 @09:16AM (#1094255) Homepage
    Okay, here's my take on the security thing. As of now, they are implementing TCP/IP over their satellite signals. I assume that they do not have the ground-based receiver connected to the public Internet, so there's not a whole lot of risk. Of course, then we get to the fun part.

    At some point in time, it is likely that researchers using the Internet proper will be able to communcate with a satellite. At that point, yes, there is a possibility of malicious individuals (or groups) getting into your sattellite. At least one barrier to entry would be the ground station-to-satellite link. If you kept this secure (using open and tested protocols and such), a malicious entity would require both a ground station of their own and strong knowledge of the ground-satellite signal specifications and protocols.

    If you set the satellite to only act on signals coming from known-good ground stations (based on geophysical location), then a ground station would have to be compromised in order to take over a satellite. This would add another layer of security.

    If you, say, hard code those coordinates and the verification routines (and make sure you don't pull a Hubble), you could be fairly certain that your satellite can't be controlled by anyone else, except through your links. If, then, you use secure connections through said link (which means keeping the stuff current, of course), you should be fine.

    All in all, it should be no easier to maliciously control a 'Net sat than it is to use an existing attack against the current generation. (Disclaimer: I am not a rocket scientist, although I did take a class covering the basics.)
  • Check out direcpc.com I have had satelite internet from them for months - about 9 times faster than a 56k modem.
    Granted it is just a router really but still - it's cool. I get the internet and Directv off of one dish.

    (You still have to have a modem and dialin for the outgoing traffic...)
  • Frankly, I'm a little worried. Sure, it's way cool to have a satellite on the Internet, but, come on, control it's position from the Internet? At least I hope they have some very good VPN and authentication set up (for when they do have control- I get the impression it wasn't set up for that yet, heres hoping it never does.)
    Security critical components should be on a private network. Sure, use TCP/IP, TCP/IP rocks, but if you are going to have remote control I for one would be far more relaxed if you were on a private network (the solar system intranet!).

    Maybe I'm overreacting, but I can't help looking up to the sky, thinking of a script kiddy, and ducking under cover.
  • This reminds me of a comment I once read in the source of a TCP/IP stack (KA9Q probably) to the effect that IP would be no good for communication in space as the round trip time to Mars would cause standard IP to time out every packet. Damnit, why didn't they see this coming back in the seventies? :-)
    --
  • Well,

    Actually, satellite ground systems are already using TCP/IP. Ground systems communicate through the satellite on special commanding boxes, but those boxes get their commands through ethernet.

    Now, many amateurs receive signals from satellites, then decommutate and decode the telemetry. The old style C band satellite dishes work for this, they just need a little refit. One COULD command a bird with more hardware and some hacking - the US and USSR did it to each other's birds during the cold war.

    What's my point? I don't think this necessarily makes satellites more vulnerable. After all, the commanding and payload (commercial signals) ususally pass through different paths, and the command paths have a bit of security involved, including encryption chips with closed-source algorithms, courtesy NSA. That encryption applies only to US owned birds, BTW.

  • Everyone and their brother would then /. the server so that they can have orbital tcp/ip traffic...

    Not to mention the script kiddies wanting to "0w/\/" it...
  • Back before Network Solutions took over the Internet, and Jon Postel et al. were in charge of numbers, the official registration for net 127.0.0 belonged to the University of Mars. Alas, today it's just the property of IANA.

  • Independence Day (Score:3)

    by Sinjun ( 176671 ) on Wednesday May 03, 2000 @08:42AM (#1094288)
    Wait a minute ... now aliens can come down and upload a virus to our satelites. We're opening the backdoor to alien hackers!
  • "Wow, There's an interstate highway in Hawaii [asce.org]!! I'm going to drive there after I get off work this evening...."

    Have you ever heard of private networks? You can have a TCP/IP network with its own internal numbering and no connection to the outside internet. What router did you think would pass your packets to the satellite's uplink antenna?

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