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WiFi without internet on a Southwest flight

jamesbvaughan.com

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Re: WiFi without internet on a Southwest flight

#621

Post by nerdbert »

cromka wrote: post #535
commandlinefan wrote: post #205

When my son was younger - maybe 9 or 10 or so, we were on a plane and he was using his phone and I looked over his shoulder and realized he was on the internet... but I hadn't paid for an internet plan. I said, "son, how are you using the internet?" He said, "oh, a kid at school showed me - if you go here" (he opened up the wifi settings where the DHCP assigned IP address is) "and start changing the numbers, eventual…

There’s a way to workaround virtually any kind of gated Internet access: DNS tunneling ( https://github.com/yarrick/iodine ) It’s slow, but it works and is a handy “last resort” tool.

Painfully slow. I would not call it usable for any modern workflow.

Re: WiFi without internet on a Southwest flight

#622

Post by IIsi50MHz »

nottheengineer wrote: post #562
barrkel wrote: post #557

Earlier quoted context omitted.

How long ago was this? 20 years ago, all I saw were dual mono bayonet jacks you'd need an adapter for to plug in normal headphones, but straws would get you nowhere. I was curious so I searched: https://simpleflying.com/inflight-entertainment-headphones-e... - pneumatic headphones from the 1960s were used on Delta as late as 2003, but electronic headsets debuted on 767 in 1982. Apparently the dual mono jacks are to d…

Then why isn't at least one of those jacks a TRS so you can use normal headphones?

My last four flights used only stereo 3.5mm plugs.

Re: WiFi without internet on a Southwest flight

#623

Post by daveevad »

cutemonster wrote: post #551
daveevad wrote: post #441

Earlier quoted context omitted.

> The other person will get frustrated and disconnect and reconnect a few times, and finally give up and read a book... That makes me really reconsider my past struggles with this form of Internet access.

Time to consider instead: walk through the plane, look angrily at the other passengers, one at a time, asking: "Do you use 192.168.x.y?". That can solve the problem

Presumably there is a way to find out which other wireless client is impersonating another in a confined environment like an airplane.

A multicast packet might vary based on physical distance to the imposter?

Re: WiFi without internet on a Southwest flight

#624

Post by yebyen »

herpderperator wrote: post #606
withinboredom wrote: post #409

Earlier quoted context omitted.

Its wifi. You both just pick up the same frame when it is broadcast, then it sees two stations (a level below IP) with the same MAC. Most routers just don't care about that. (it's technically a valid edge case that two stations have the same mac address. It should be vanishingly rare in the wild ... but this is a practical example of why it isn't).

So if two wifi clients have the same MAC and IP, everything works fine for both of them?

"everything works fine" might be overstating a bit, but what happens to packets you weren't expecting when you don't have a connection open for them to go into? They probably get ignored by the network stack.

Worst case scenario, the router/service endpoint sees your connection responses and the other party's strange NACK responses, but I honestly don't know enough about how it works to say "everything works fine"

I'd guess that connectionless protocols will work fine and connected protocols will also work fine. The truth is probably YMMV by protocol, but there is truly no way for the wifi router to detect this is happening or isolate the redundant stations - it's an unencrypted broadcast. The only way this goes sideways is if a connection protocol is engineered to make it go sideways when you try to do that.

I'm pretty sure that any such protocol which succumbs to any unencrypted (or incorrectly keyed) traffic that isn't from the designated counterparty is insecure to begin with. It should be resilient against DoS, so most protocols aren't going to have that vulnerability. Again, I'm guessing, but I'd hope.

Re: WiFi without internet on a Southwest flight

#625

Post by akira2501 »

mikepurvis wrote: post #78
jasonjayr wrote: post #15

Earlier quoted context omitted.

... Which is precisely the data those data loggers you plug in from insurance companies track to adjust/refine your rates .....

Honestly, it seems pretty fair to me. If I'm a careful, occasional driver, and the insurance company otherwise has no way of knowing that, then they have to bill me like I'm commuting every day in stop and go traffic, distracted by podcasts and who knows what else. There will probably always be a "premium" market for no-questions-asked insurance, but if the company can give me a break on my rate based on my driving b…

The majority of fatalities involve drugs or alcohol, they often involve youth and speed, and occur at night. Many insurance claims involve single vehicle accidents and weather or other wear related damage. The most common two vehicle claim is rear ending into a stationary vehicle, where it's not particularly difficult to determine fault.

Further, none of this matters all that much if you have a straight liability only policy, since that's based on liability of damages and not replacement property values.

These devices make very little sense to me and I'd be curious to know if anyone has any data that the presence of these devices is having any impact whatsoever.

Re: WiFi without internet on a Southwest flight

#626

Post by dramm »

phkahler wrote: post #591
dramm wrote: post #136

“According to this data, the plane’s altitude was only fluctuating by about 20-30 feet. This is more stable than I expected!” Autopilots are very good and they are servoing to the pressure altitude. Many pressure altitude encoders used in modern aircraft (for example to drive altitudes that transponders report to SSR radar or via ADS-B) have 25 ft encoding resolution. That 25ft resolution is likely what is being seen…

>> Autopilots are very good and they are servoing to the pressure altitude. It would have been cool to use a phone to record a GPS track with altitude and compare them. Pressure != GPS. Also wonder if there would be distinct jumps in the difference if they reset the pressure based altimeter to a different AWOS. Not sure how it works in big planes, but in little ones you need to set your altimeter based on the local w…

The QHN/Kollsman window setting only affects what is displayed to the wetware. When you strip away all that the autopilot is just servoing to a pressure altitude. But sure if you are flying below the transition altitude and are flying between areas with different QNH settings when you adjust the setting the autopilot will climb or descend as needed because you told it to servo to a different pressure altitude.

There are many EFB (e.g. Foreflight), or log book, or other flight recorders you can use on an iPhone. And some can record the pressure transducer in the iPhone to record an approximate "pressure altitude". e.g. Naviter SeeYou Navigator intended for gliders can do that (but it's not unusual for modern gliders to have an array of sophisticated air data sensors and specialized variometers and flight computers that would feed the app this data over Bluetooth). Popular EFB software Foreflight will not use the iPhone pressure transducer, if you want pressure data there you need to drive that through an external interface like a Sentry ADS-B receiver that has a pressure sensor built into it -- or much better if the aircraft is equipped with ADS-B Out can receive the "own-ship" ADS-B Out broadcast pressure altitude from it's high accuracy encoder). Any in-cabin pressure traducer will be sensitive to the difference between calibrated static pressure and cockpit pressure, things like opening or closing vents, or varying the airspeed significant (and ram air pressure or suction on the cockpit exit vents) can cause observable changes. And when using an iPhone or similar, especially without a great GPS satellite overhead view (e.g. in high wing aircraft) you are likely not to get high-quality GPS altitude data. think best case ~ +/- hundred feet, worse case with little overhead GPS sat view, much worse... but those consumer GPS app is likely to happily display multiple decimal points of precision :-)

Re: WiFi without internet on a Southwest flight

#628

Post by inopinatus »

aftbit wrote: post #613
inopinatus wrote: post #516

Earlier quoted context omitted.

A quick review of published information reveals this claim as false. A typical airliner FMS feeds information to IFE via gateway devices. The integration is intended to be one-way. Airgapped they are not. Such analytical delusions are the first step on the road to failing to adequately mitigate threats. As practiced by “it can’t happen here” school of fucking up. Fortunately, it seems far more likely that aircraft sy…

Documentation please?

The talk above is available online.

Re: WiFi without internet on a Southwest flight

#629

Post by mikaraento »

nottheengineer wrote: post #562
barrkel wrote: post #557

Earlier quoted context omitted.

How long ago was this? 20 years ago, all I saw were dual mono bayonet jacks you'd need an adapter for to plug in normal headphones, but straws would get you nowhere. I was curious so I searched: https://simpleflying.com/inflight-entertainment-headphones-e... - pneumatic headphones from the 1960s were used on Delta as late as 2003, but electronic headsets debuted on 767 in 1982. Apparently the dual mono jacks are to d…

Then why isn't at least one of those jacks a TRS so you can use normal headphones?

On newer planes both of them often are

Re: WiFi without internet on a Southwest flight

#630

Post by kabes »

commandlinefan wrote: post #205

When my son was younger - maybe 9 or 10 or so, we were on a plane and he was using his phone and I looked over his shoulder and realized he was on the internet... but I hadn't paid for an internet plan. I said, "son, how are you using the internet?" He said, "oh, a kid at school showed me - if you go here" (he opened up the wifi settings where the DHCP assigned IP address is) "and start changing the numbers, eventual…

I used dns tunnels a lot in the past. I wonder if techniques like this still work these days
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