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Unifying Undersea Wireless Communication Using TCP/IP

Unknown Lamer posted 1 year,15 days | from the whales-need-internet-too dept.

Wireless Networking 68

Nerval's Lobster writes "Wireless and cellular networks cover beaches and extend over the ocean to ships at sea but not, so far, under the ocean. A team of researchers at the University of Buffalo believe they've solved at least the technical problem of how to push wireless networking signals for long distances through the deep ocean to connect offshore oil and gas platforms, floating and underwater tsunami sensors and other remote facilities without having to bounce signals off a satellite first. Radio waves tend to be smothered or distorted by travel through water; most ocean-based sensors use acoustic waves instead, which link sensors into underwater acoustic sensor networks (UWASN). The team designed a low-power IPv4/IPv6-compatible networking protocol that uses very low power, compresses headers, is tolerant of fragmented data and connection delays, allows bi-directional communication with (and reconfiguration of) existing underwater sensors and is compatible with standard TCP/IP networks and IP router proxies. The approach is more than a simple translation from one networking medium to another. It leaves the higher-level TCP/IP networking protocols intact, but adds an adaptation layer between the data-link layer and network layer that compresses headers, changes packet size, transmission time-out settings and other requirements to be compatible with slower underwater transmissions. The team tested the implementation using a Linux-based driver, both PC and ARM-based computers and a Teledyne Benthos SM-75 Modem. They sealed two network nodes in 40-pound waterproof cases, dumped them into Lake Erie near Buffalo and transmitted instant-messaging signals from the application IPTUX from one to the other. They were also able to transfer files using FTP from an underwater client to server."

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And the ping command comes full circle (5, Funny)

toygeek (473120) | 1 year,15 days | (#45129035)

^ subject says it.

Re:And the ping command comes full circle (4, Funny)

camperdave (969942) | 1 year,15 days | (#45129067)

Verify the hop count to the target, Vasily ; one ping only.

Re:And the ping command comes full circle (1)

Joe_Dragon (2206452) | 1 year,15 days | (#45129197)

Contact has gone active sonar

Ping! Starring Sean Connery (1)

Anonymous Coward | 1 year,15 days | (#45129207)

vborodin@roctober:~$ man ping | grep 'hop count'
vborodin@roctober:~$

Vasily: "Captain, I cannot get a hop count using ping."
Captain: "Damn. They must be close!"

Re:And the ping command comes full circle (1)

Anonymous Coward | 1 year,15 days | (#45129209)

The missile boat captains of the world scream in terror at the prospect of cat pictures revealing their position.

Re:And the ping command comes full circle (2)

davester666 (731373) | 1 year,15 days | (#45129895)

More likely they will wonder why their launch computers need a public IP address...

Re:And the ping command comes full circle (2)

K. S. Kyosuke (729550) | 1 year,15 days | (#45130431)

Verify the hop count to the target, Vasily ; one ping only.

Will an ICBM packet follow the ICMP packet? Or will they just opt to initiate a Torpedo Control Protocol session?

Re: And the ping command comes full circle (0)

Anonymous Coward | 1 year,15 days | (#45129287)

That should be +5..

Give it time Re: That should be +5.. (2)

davidwr (791652) | 1 year,15 days | (#45129459)

Moderating /. posts takes longer under water.

Shitty (5, Funny)

ShieldW0lf (601553) | 1 year,15 days | (#45129047)

It's a shitty day to be a whale.

Re:Shitty (0)

Anonymous Coward | 1 year,15 days | (#45129087)

Not only in the South, but also in the North. Right here in New York City.

Re:Shitty (3, Informative)

Anonymous Coward | 1 year,15 days | (#45129323)

Considering the recent story submitted to /. about the US Navy's noise causing whales to beach themselves... yeah, yeah it is. I hope they take impact on wildlife into account when developing this.

Re:Shitty (1)

Anonymous Coward | 1 year,15 days | (#45129339)

" I hope they take impact on wildlife into account when developing this. " - I'm sure they will give exactly 1 damn, publicly at least.

Re:Shitty (-1)

Anonymous Coward | 1 year,15 days | (#45129749)

How do I tell a beached whale apart from a typical American sunning themselves?

Re:Shitty (3, Funny)

narcc (412956) | 1 year,15 days | (#45129983)

The whale will be bilingual.

Re:Shitty (0)

Anonymous Coward | 1 year,15 days | (#45130007)

How do I tell a beached whale apart from a typical American sunning themselves?

The better odour of the whale?

Re:Shitty (0)

K. S. Kyosuke (729550) | 1 year,15 days | (#45130447)

I hope they take impact on wildlife into account when developing this.

21th century: whales are the new Indians?

Re: Shitty (0)

Anonymous Coward | 1 year,15 days | (#45129611)

Do people really imagine sea creatures won't be bothered by acoustic spectrum frequencies!?

Re:Shitty (1)

marcello_dl (667940) | 1 year,15 days | (#45130649)

It goes both way.

Joins: UF|slaughterer
[AA]wjcked: slaugherer, your ping sucks!
UF|slaughterer: sry
[AA]wjcked: stop mating calls to whales LOLOLOL
UF|slaughterer: f*ck you

the whales are going to love this (0)

Anonymous Coward | 1 year,15 days | (#45129083)

more acoustic signals. Nice.

OK, OK I didn't read the previous post (0)

Anonymous Coward | 1 year,15 days | (#45129095)

sorry

Re:OK, OK I didn't read the previous post (1)

davidwr (791652) | 1 year,15 days | (#45129461)

I blame underwater latency.

So they had a field day (0)

Anonymous Coward | 1 year,15 days | (#45129121)

Actually not easy to find specs on this souped-up accousticoupler. All the important bits were left out, so bad article.

US Navy Submarines Tasked To TAP Offshore Fiber (0)

Anonymous Coward | 1 year,15 days | (#45129213)

NSA now has yet another headache as well as the US Navy.

US Navy nuclear submarines have been used to tap into undersea fiber cable to intercept communications from the Kremlin to his "assets" abroad.

Now, the NSA is tasking those same US Navy submarines to again tap the undersea cable to "carpet bomb download" all communications of US citizens.

An anonymous source within USN Ops said with a laugh, "every US citizen in the US is a target to be killed at some point in time when the President deems it expedient."

Well, there you have it from the "Freddy's Nightmare on Pennsylvania Avenue, D.C." :D

Redux of NASA's Disruption Tolerant Networking? (1)

petsounds (593538) | 1 year,15 days | (#45129231)

Isn't this just a parallel implementation to NASA's space-tuned TCP/IP stack, designed to communicate under similar conditions between objects over far longer distances?

Similar conditions? (1)

davidwr (791652) | 1 year,15 days | (#45129467)

Sound travels in space? Who knew???

Re:Similar conditions? (3, Interesting)

Neil Boekend (1854906) | 1 year,15 days | (#45129575)

Long delays.
Sound travels at the speed of sound, which is a lot slower than light causing large delays. In space things are simply so far away that the light speed delays are similar.
If you have a 3 hour delay you do not wish to use the default TCP/IP, because the syn/ack phase would take hours.
My best guess is that you have a quite long sync phase and then just send the data and wait for confirmation that it's received correctly after sending everything. If it isn't received correctly you send the parts that went wrong again.

Re:Similar conditions? (1)

Anonymous Coward | 1 year,15 days | (#45129825)

In space, nobody can hear you ping.

Re: Similar conditions? (1)

chill (34294) | 1 year,15 days | (#45129943)

Hollywood directors guild.

Re:Redux of NASA's Disruption Tolerant Networking? (4, Informative)

sehgalanuj (2057492) | 1 year,15 days | (#45129499)

Not quite. Acoustic networking is a necessity in water, as compared to eM in space. Acoustic networking is also notorious for being easily influenced by its ambient environment (temperature, pressure, acidity, salinity). Not to mention the long delays, which can easily vary over the course of a single day many times. Add to this the mix of those special ambient conditions that can lead to "black-holes" where sound from outside doesn't enter, and you've got a mix of an environment that is a pain to handle.

That said, I am not sure the authors' work on essentially porting 6LoWPAN to UWAN is the right way to go since it doesn't account for many things, but it is a step in the appropriate direction. Though, honestly, equipping underwater sensors or vehicles with IP networking might be a bit of an overkill.

Re:Redux of NASA's Disruption Tolerant Networking? (1)

viperidaenz (2515578) | 1 year,15 days | (#45129657)

So you mean just like in space, where you have long delays, background radiation, solar flares, planets, moons, comets and asteroids getting in the way...

Re:Redux of NASA's Disruption Tolerant Networking? (5, Informative)

sehgalanuj (2057492) | 1 year,15 days | (#45129781)

Close, but not quite the the same. I understand that background radiation, solar flares, planets, moons, comets and asteroids have a negative impact upon radio communication. However, this is something that we do understand how to deal with in some respect, given our history of working successfully with radio. I am not trying to say it is easy, but the challenge there is within the scope of technology that is better understood.

Also, while all those factors you mentioned pose problems, the underwater acoustic channel is still more volatile. Imagine a temperature shift of one degree, i.e. from morning to evening, completely changing your delay factor. Not just that, but as a result now your ideal frequency and power combination that obtains you optimal bandwidth is also different. Underwater nodes are also notoriously hard to get power to (and yes, I understand that there is no power station sitting in space either, but you still do have access to energy gathered from solar radiation and etc.), which makes switching all of this really hard to do.

Now add the factor that the depth of your transmitter and receiver might be different, and this results in both of them having a different set of optimal (or near optimal) communication requirements. Both might even have different windows of opportunity to work in, making synchronization near impossible to achieve. This is not counting the problem of ambient noise that keeps changing based on surface winds, thermal effects and waves. Add to this multi-path echoes that are quite plenty and you start to get an idea of some of the many issues that this channel is faced with.

In the end, yes, both channels are similar in the fact that there are long delays and to some extent these might vary in space as well. But the very nature of the underwater acoustic channel is different from radio in space. There might be some things that can be learnt from NASA's space-tuned TCP/IP stack, but in general, TCP/IP is a bad idea in a channel that can hardly carry a few bits at a time. In the case of 6LoWPAN, which the authors of the paper in question look to for inspiration, they have still more bits than what you get underwater. Header compression and similar things can help, but in the end, fragmentation and reassembly is not the best approach. Hence my previous statement that maybe, TCP/IP is not the best idea for underwater acoustic channels.

TLDR: Yes, the two channels have some similarities, but they are not the same thing. Will there be things that can be learnt by each field from looking at solutions in either fields? Sure, but that doesn't cover it all.

Re:Redux of NASA's Disruption Tolerant Networking? (2)

Solandri (704621) | 1 year,14 days | (#45133809)

Also, while all those factors you mentioned pose problems, the underwater acoustic channel is still more volatile. Imagine a temperature shift of one degree, i.e. from morning to evening, completely changing your delay factor.

It's worse than that. The water temperature (and pressure) changes with depth, which means the speed of sound does as well. This causes sound initially heading down to arc back up, until it hits the surface and heads back down again and repeats (fig 12) [fas.org] . Consequently, any sound which isn't traveling a short enough distance that it can travel straight to the target gets smeared out over time due to multipath.

It leads to some interesting phenomena. A thermocline (layer of water with an abrupt temperature change) can refract the sound enough to prevent it reaching anything underneath. Submarines sometimes use this to hide from sonar, but it will also block any listening devices you have from hearing what a surface station is broadcasting. And a SOFAR channel [wikipedia.org] where the temperature forms an acoustic waveguide, allowing you to transmit sounds around the globe with little loss (though it adds a lot of distortion due to the multipath). Whales use this to "broadcast" their songs for thousands of miles.

Faster networks in less than ideal conditions (0)

Anonymous Coward | 1 year,15 days | (#45129251)

It leaves the higher-level TCP/IP networking protocols intact, but adds an adaptation layer between the data-link layer and network layer that compresses headers, changes packet size, transmission time-out settings and other requirements to be compatible with slower underwater transmissions

Uhm, screw the crabs, shouldn't above water networks also be trying to solve the same problems??

Re: above water networks ... same problems (1)

davidwr (791652) | 1 year,15 days | (#45129473)

I wonder if this can be adapted to carrier pigeon [ietf.org] -based networks?

Uhm, no (0)

Anonymous Coward | 1 year,15 days | (#45129491)

Uhm, screw the crabs,

badimageinhead! getitout! donotwant! arrrrghhhhhhhhhh!

Someone shoot me now.

Re:Uhm, no (0)

Anonymous Coward | 1 year,15 days | (#45129773)

Mmmmmm crab clam .....

Nice :)

Trans-cranial dual wireless audio-chemical signals (1)

VortexCortex (1117377) | 1 year,15 days | (#45129275)

Acoustic communication? Phrbrrrarrbrbrt! ...tssss!

One does not simply Talk into water.

I thought it was a total blackout here in the USA? (-1)

Anonymous Coward | 1 year,15 days | (#45129305)

Why Slashdot is still running ?

You'd better go to the market and see your future stock exchance : US Stock Market [youtube.com]

Re:I thought it was a total blackout here in the U (0)

Anonymous Coward | 1 year,15 days | (#45129457)

Let's replace the do-nothing Congress with Slashdot moderators instead.

Radio waves are completely blocked by water. (0)

gaijin_ (134592) | 1 year,15 days | (#45129341)

Its a big understatement to say that they "tend to be smothered or distorted by travel through water". They don't travel through water.

Re:Radio waves are completely blocked by water. (5, Informative)

gargeug (1712454) | 1 year,15 days | (#45129405)

Yes they do travel through water. Their attenuation is frequency dependent and is given by the skin depth of water. Lower frequency waves propagate further than high frequency. At the wireless frequencies, water highly attenuates its propagation such that it can only communicate a few meters, but submarine ELF frequencies (73 Hz) can penetrate on the order of 1 km with only 60 dB loss or so, and ionospheric waves (approx .5 Hz) go through the complete ocean and into the lithosphere. [Source: Me. I am currently doing heavy research into this subject for a research contract] As a layman thinking only of WANs and 2.4 GHz stuff I could see how you could make this mistake, but what you way is false. Even GHz waves will travel, albeit an insignificant amount, but still finite.

Re:Radio waves are completely blocked by water. (1)

AHuxley (892839) | 1 year,15 days | (#45129501)

Yes ELF and VLF stations make for interesting reading world wide http://en.wikipedia.org/wiki/Naval_Communication_Station_Harold_E._Holt [wikipedia.org]
http://en.wikipedia.org/wiki/Communication_with_submarines [wikipedia.org]

Re:Radio waves are completely blocked by water. (1)

Muad'Dave (255648) | 1 year,14 days | (#45130957)

Here's a site [www.vlf.it] that has good info about using your sound card as an ELF receiver - you hook an antenna right to the mic input since the 'RF' involved uses the same frequencies as we humans hear (and are generated by microphones, etc).

Re:Radio waves are completely blocked by water. (1)

delt0r (999393) | 1 year,15 days | (#45130305)

How much reflection do you get at the water/air interface with ELF?

Re:Radio waves are completely blocked by water. (2)

gargeug (1712454) | 1 year,14 days | (#45131777)

A lot. Air is almost non-conductive, whereas seawater is highly conductive, so the interface is highly reflective, and refractive.

Re:Radio waves are completely blocked by water. (1)

thygate (1590197) | 1 year,14 days | (#45130835)

Well a 70 Hz carrier doesn't quite give you enough bandwidth to run even a silly 1200 bps UART. With radiowaves in the microwave range (like your 2.4GHz) water absorbs most of the energy and turns it into heat. Like your microwave oven does. The water dipole attempts to continuously reorient in electromagnetic radiation's oscillating electric field. Dependent on the frequency the dipole may move in time to the field, lag behind it or remain apparently unaffected. When the dipole lags behind the field then interactions between the dipole and the field leads to an energy loss by heating.

Re:Radio waves are completely blocked by water. (2)

gargeug (1712454) | 1 year,14 days | (#45131861)

Yes, thats all true. As I said above, its penetration depth is given by the frequency dependent skin depth of the medium. BUT, some things don't need much bandwidth, nowhere near as much as 1200 bps. And if the navy invested millions into a 28 mi antenna to produce that 76 Hz, the low bandwidth it gets, and the concept of radio in seawater, is obviously not that silly. http://en.wikipedia.org/wiki/Project_Sanguine [wikipedia.org]

Re:Radio waves are completely blocked by water. (1)

sjames (1099) | 1 year,14 days | (#45132909)

Yes, that will give you 35 bps maximum. Given the natuire or the medium and background, I wouldn't imagine QAM would work very well.

Re:Radio waves are completely blocked by water. (0)

Anonymous Coward | 1 year,14 days | (#45133307)

With radiowaves in the microwave range (like your 2.4GHz) water absorbs most of the energy and turns it into heat. Like your microwave oven does.

My microwave penetrates food and heats it from the inside. They picked that frequency, because it penetrates water, while still being absorbed. There is not peak absorption at 2.4 GHz or a special resonance there. That's an urban legend.

Re:Radio waves are completely blocked by water. (0)

Anonymous Coward | 1 year,15 days | (#45129561)

Me think you should be talking about this subject with US DoD... they have been communicating with their submerged missile carrying nuclear submarines for the past 40 years using VLF/ELF... ...and I suppose the sovjets has been doing the same.

Re:Radio waves are completely blocked by water. (1)

Animats (122034) | 1 year,15 days | (#45129579)

Even 100MHz RF will get through tens of meters of water. Ground penetrating radar systems [sensoft.ca] can image through shallow water and into the ground underneath. The losses are huge, but remember that you can send very high power pulses and detect microwatts.

Under The Sea (1)

Anonymous Coward | 1 year,15 days | (#45129357)

Under the sea,
Under the sea,
There'll be no radiation,
Just horny crustaceans
Under the Sea!

Whales and dolphins better learn how to shoot (0)

Anonymous Coward | 1 year,15 days | (#45129389)

There is really nothing these water-based mammals can do to preserve their sanity, at this point. And humans won't respect them unless they fucking SHOOT at us.

Re:Whales and dolphins better learn how to shoot (0)

Anonymous Coward | 1 year,15 days | (#45129429)

Nobody ever suspects the killer whales.

CAPTCHA: profit.

Re:Whales and dolphins better learn how to shoot (3, Funny)

viperidaenz (2515578) | 1 year,15 days | (#45129663)

How are they going to shoot us? Only sharks have lasers on their heads.

finally (2)

lkernan (561783) | 1 year,15 days | (#45129463)

Finally, Spongebob gets dialup!

Re:finally (1)

thygate (1590197) | 1 year,14 days | (#45130947)

At those frequencies (ELF/VLF) there's isn't too much bandwidth. Maybe enough for sensor buoys to send a few bytes every few minutes. But it's not even going to get close to even 1200 bps.

Obligatory puns (1)

antifoidulus (807088) | 1 year,15 days | (#45129649)

And protect it with blowfish!

Thank you, thank you, I will be here all week, and remember, download the fish!

Oh great (1)

Freshly Exhumed (105597) | 1 year,15 days | (#45129653)

After all these years the mortgage on the undersea VLF Numbers Station was finally paid off, and now this... this!!!

Kim Dotcom (0)

Anonymous Coward | 1 year,15 days | (#45130591)

He's probably already thinking of putting a server in international waters...

Laugh (1)

koan (80826) | 1 year,14 days | (#45130891)

Sounds like a bad idea all the way around.

Where's the actual interresting stuff ? (1)

thygate (1590197) | 1 year,14 days | (#45130907)

And yet another high level layer to cope with high-error-rate and slow physical layers. But the problem remains the attenuation of RF underwater. Where are the interesting details, like the carrier frequency, modulation type, bandwidth, power efficiency etc ..

Re:Where's the actual interresting stuff ? (1)

drinkypoo (153816) | 1 year,14 days | (#45131819)

Where are the interesting details, like the carrier frequency, modulation type, bandwidth, power efficiency etc ..

I poked around and it seems to be an obsolete product. 9-14 khz frequency, though.

Re:Where's the actual interresting stuff ? (0)

Anonymous Coward | 1 year,14 days | (#45135125)

... the problem remains the attenuation of RF underwater. Where are the interesting details, like ...

the fact it is acoustic, not RF?

They really want to kill all the whales.. (1)

vanuda (1539873) | 1 year,14 days | (#45131445)

Sound is a generic way of communicating between sea animals.. What would you say if you had a ping-ping-ping in your ears all day long... Regardless frequency..

effects on aquatic animals? (1)

museumpeace (735109) | 1 year,14 days | (#45131619)

Sonar is bad for wales and dolphins, but wait until you have flashmobs of zebra mussels.

news to me (0)

Anonymous Coward | 1 year,14 days | (#45132437)

i did not know there is a need for underwater wireless communications. i learned something new. thanks for sharing

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