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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

#521

Post by benced »

benced wrote: post #38

Another thing to notice: they use the highly nonstandard time zone abbreviation “PDT”. This works because they’re a US-only airline but if an international airline did this, they’d be in for a world of hurt.

To anyone claiming they're standard:

> Time zones are often represented by alphabetic abbreviations such as "EST", "WST", and "CST", but these are not part of the international time and date standard ISO 8601 and their use as sole designator for a time zone is discouraged.

> Such designations predate both ISO 8601 and the internet era; in an earlier era, they were sufficiently unambiguous for many practical uses within a national context (for example, in railway timetables and business correspondence), but their ambiguity explains their deprecation in the internet era, when communications more often cannot rely on implicit geographic context to supply part of the meaning.

https://en.wikipedia.org/wiki/List_of_time_zone_abbreviation...

Turns out PST and PDT are safe (no one else seems to use them) but something like CST is not: it could mean Central Standard Time (America/Chicago during standard time) or several other choices like China Standard Time (Asia/Shanghai).

Ambiguity is bad.

Re: WiFi without internet on a Southwest flight

#522

Post by benced »

SirMaster wrote: post #24

I want to see someone build a proxy that uses the free iMessage or WhatsApp allowed connection to send arbitrary data. Like have a WhatsApp relay set up at home that you are sending messages to and from, from the plane. Like at a most basic level, send a message of a URL to your home WhatsApp which loads the web page there, and sends the HTML back as a WhatApp message reply so you can render it etc. Wonder what someo…

I believe this is the approach that Flighty (https://flightyapp.com/) uses to send flight updates while on non-paid Wifi.

Re: WiFi without internet on a Southwest flight

#523

Post by prmoustache »

pbj1968 wrote: post #463
xvedejas wrote: post #267

Earlier quoted context omitted.

That's significantly slower than a typical elevator, in fact. Slow elevators run at about 200 feet per minute.

My elevator takes almost a minute to go from the first floor to the second floor. I guess I have a slow one.

Nobody without disabilities would use such an elevator.

Re: WiFi without internet on a Southwest flight

#524

Post by cereal_cable »

withinboredom wrote: post #418
richardwhiuk wrote: post #412

Earlier quoted context omitted.

If there's multiple hotspots behind the same controller, you may well get switch port fighting.

If STP[1] is enabled, but that is unlikely since you'd have dropped connections when roaming for the reasons you just gave. Most likely, STP is not enabled on these networks. [1]: https://en.wikipedia.org/wiki/Spanning_Tree_Protocol

A switched port learns the Mac address for packets sent into it. If port 1 sends a packet with Mac a, the switch associates that address (a) to port 1. When another node sends a packet onto another port with the same mac, say on port 2, the switch will move the learned address a to port 2 and remove it from port 1.

When a switch has learned a mac address all traffic destined to that traffic would be immediately switched to that port. If the switch has no record for that specific mac address it floods all ports except the ingress port. This is expensive and means other devices receive traffic that isn't intended for them so they waste time dropping it.

So in networks that have no protections against those attacks then this could very well be a problem if there are multiple access points and the two nodes are on different access points.

Re: WiFi without internet on a Southwest flight

#525

Post by catiopatio »

turquoisevar wrote: post #498
catiopatio wrote: post #118

Earlier quoted context omitted.

> amazing engineering Background updates are a built-in, supported, documented feature, widely employed by applications on the platform, and accessible to anyone that reads the two pages of documentation required to use them: “Pushing background updates to your App — Deliver notifications that wake your app and update it in the background.” https://developer.apple.com/documentation/usernotifications/... edited for po…

I don’t know what you have against Flighty but you through considerable lengths in the thread below to spend time on letting everyone know how unimpressed you are about their efforts. Your lack of amazement is duly noted, I suggest you don’t waste any more time on it. That said, I, like others, are indeed impressed for a couple of reasons. For starters because of the simple fact that they’ve found a novel way to use…

You’re right, I see that as embarrassingly trivial. This whole thread is inane — if using a simple API is “amazing engineering”, what do you call the actual amazing engineering you’re holding in your hand right now?

I have nothing against Flighty — this has nothing to do with Flighty. Background notifications are trivial and all apps can and should be using them to solve this type of problem. It’s detrimental to have folks mistakenly operating under the belief that this is complex, unusual, or difficult.

Sure, the payload size is limited, but it’s not impossibly small, and custom keys with arbitrary payload are explicitly and obviously documented as supported.

Overly-effusive praise doesn’t do anyone any favors.

Re: WiFi without internet on a Southwest flight

#527

Post by H8crilA »

You can also get an SDR (a $50 RTL-SDR will do) and listen to your own plane's ADS-B signal. For visualization you can use tar1090. Private Flightradar24.

With the same SDR you can also listen to the ATC comms, as well as see ACARS messages. It's a bit tedious to listen to ATC and your own pilots, but you'll know exactly why your plane is delayed.

Re: WiFi without internet on a Southwest flight

#528

Post by simonjgreen »

dramm wrote: post #457
jjwiseman wrote: post #284

Earlier quoted context omitted.

I don't know what sensors are feeding the API from the post, but most passenger jets do broadcast information about the accuracy of their sensed position, including vertical position/altitude. If you click on an aircraft on the map at https://globe.adsbexchange.com/ , and scroll the left sidebar all the way to the bottom you'll see a section labeled "Accuracy". ADS-B Exchange doesn't show Rc/v, the vertical position…

Pressure encoders, as I said. That's what feeds all aviation altitude data... i.e. anytime you see the word 'altitude' and its not qualified with 'GPS altitude' which is effectively not normally used. ADS-B Out concurrently transmits GPS height about the ellipsoid data as well as pressure altitude data. No use is normally made of the GPS height data. We are discussing pressure altitude data here, that's what aviation…

Also worth noting that the datum used to translate from pressure to altitude switches at the transition threshold, usually 18,000ft, from actual local ground pressure (supplied by ATC in all initial contacts) to 29.92 Hg.

Re: WiFi without internet on a Southwest flight

#529

Post by H8crilA »

system2 wrote: post #262
dekhn wrote: post #184

Wait, doesn't everybody set up a prometheus/grafana dashboard for each flight to show the telemetry?

I usually connect to the cockpit directly with rj45 to keep it stable. Sometimes even talk to the pilot with the encrypted coms.

Talking to the pilots costs about $200 and is really easy, though very illegal - just find out which ATC freq are they currently on and transmit, from a handheld radio or a HackRF. You could also transmit on Guard.

If you prefer to text rather than speak you can send them ACARS, with roughly the same hardware. Though if you use a handheld radio you'll also need a laptop to generate the baseband signal, as I don't think there are any commercially available ACARS transmitters.

(Please never do this, you'll go to jail for a long time).

Re: WiFi without internet on a Southwest flight

#530

Post by svag »

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…

When I am on a flight and the flight does not provide the flight information, I am using the OsmAnd, https://osmand.net/, to monitor the flight altitude, speed and direction.
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