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Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

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Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#41

Post by simfree »

techsupporter wrote: post #38
bquest2 wrote: post #37

Earlier quoted context omitted.

With all those sims, you still have a RSSI from physical cell phone tower(s), so its still serving its purpose for fraud prevention

How so? None of the fraud prevention APIs I've seen tell you if a given number is connected to a base station, only whether it's theoretically GSM, landline, VoIP, or something else. With the ability to tunnel LTE over an unstructured Internet connection ("wifi calling,") I don't have to be within range of a single US-based base station to "appear" like I am in the US to the mobile network. And everyone tells me that…

You might check out yoursecretnumber.com as their phone numbers show up as Cellular/PCS rather than landline.

That being said short code support is middling, not quite as good as VoIP numbers that use Bandwidth.com (Google Voice uses them) or Onvoy.

Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#42

Post by newhouseb »

z92 wrote: post #15

If you can't purchase the GNSS HAT, use an old Android phone and install Termux on it. Then run some bash scripts on the phone that will do the job. The phone will communicate with your network over wifi, and replaces both the Raspberry PI and the HAT.

Also important to note that the Android approach is more likely to continue to work. In many places (certainly Manhattan, where I am), everything but LTE (and I gues 5G) has long been turned off such that GSM/Edge/UMTS/etc no longer work.

Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#43

Post by gsich »

keyme wrote: post #31

Why isn't there something that turns a rooted Android phone into a VOIP Cell network gateway? Something that allows incoming calls to be forwarded to SIP, and vice versa? I haven't found something like that.

Not possible with most devices. I wanted something similar, no result. Seemed like a hardware restriction that phone calls go to either the speaker or Bluetooth.

Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#44

Post by cromka »

z92 wrote: post #15

If you can't purchase the GNSS HAT, use an old Android phone and install Termux on it. Then run some bash scripts on the phone that will do the job. The phone will communicate with your network over wifi, and replaces both the Raspberry PI and the HAT.

I wonder if anyone tried running virtualized Android with an eSIM with VoWiFi? This way you could completely give up the need of having any hardware at all.

Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#45

Post by mindslight »

techsupporter wrote: post #34
jandrese wrote: post #22

Earlier quoted context omitted.

Do you have dozens of phone bills to pay every month?

robotmay who also replied to you is correct for what I do, I have multiple prepaid US SIMs with PAYGO rate plans. It's trivial to get many of these and register them in bulk to get "real" mobile numbers. (This is why I laugh and laugh at people who insist that VoIP numbers are more "fraudulent" because of whatever. Right now, breaking no rules whatsoever, I can get a hundred mobile numbers that any service will accep…

It's been a while since I looked, but the cheapest US paygo plans are still at least $3/mo (eg H2O wireless), and probably double that if you want more convenient billing. Have you found something better, or are you deriving that much utility from scaling to many devices or what? I'd think if the goal is signing up a bunch of accounts, one would be content with a single plan or maybe two, and just periodically swapping their phone numbers.

It seems like it would be easy enough to change your setup to hide your actual location by locating the gateway elsewhere and backhauling with its own IP connection.

BTW are there any standard interoperable formats for transmitting/presenting/archiving text messages, akin to Maildir for email or SIP for voice? If not, maybe Maildir is the right answer.

Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#46

Post by naivedevops »

Teever wrote: post #35
naivedevops wrote: post #33

Earlier quoted context omitted.

Maybe because nobody had a strong enough use case to feel compelled to implement it. There are very cheap GSM to SIP gateways, that are way less expensive than a mobile phone.

Do you have any links for those? I can't imagine them being much cheaper than a free used smartphone that many people have lying around or the price of a used phone from a pawnshop or ebay -- $50.

Maybe not as cheap as an used phone, but close: https://a.aliexpress.com/_mK1XuTt

Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#47

Post by ComputerGuru »

pjmlp wrote: post #26
ComputerGuru wrote: post #17

Earlier quoted context omitted.

The problem is that fixed part of most plans’ pricing make the cost prohibitive, not the pay-as-you-go component (eg the cost of a sim and phone number). We were able to use a LoRa-like layer to forward to a base station that then uses a VoIP provider to do the brunt of the communication work.

I hardly use more than a couple hundred from my 5 000 monthly budget to external networks, on the same network they are free.

I think I failed to convey my point clearly. My point is that if you need a separate sim per IoT device, the (possibly monthly) cost of a sim and number will greatly exceed the cost of messages sent.

Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#48

Post by guenthert »

newhouseb wrote: post #42
z92 wrote: post #15

If you can't purchase the GNSS HAT, use an old Android phone and install Termux on it. Then run some bash scripts on the phone that will do the job. The phone will communicate with your network over wifi, and replaces both the Raspberry PI and the HAT.

Also important to note that the Android approach is more likely to continue to work. In many places (certainly Manhattan, where I am), everything but LTE (and I gues 5G) has long been turned off such that GSM/Edge/UMTS/etc no longer work.

What? I'd think lots of IoT and other automated data service relies on cheap and less-than-bleeding-edge technology. 3G coverage seems to include Manhattan (and most of the USA): https://www.whistleout.com/CellPhones/United-States/New-York

Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#49

Post by fegul »

z92 wrote: post #15

If you can't purchase the GNSS HAT, use an old Android phone and install Termux on it. Then run some bash scripts on the phone that will do the job. The phone will communicate with your network over wifi, and replaces both the Raspberry PI and the HAT.

You could also install am app like Tasker or Macrodroid and set up triggers for handling incoming SMS (e.g. If SMS received, forward using another mechanism)

For outgoing SMS, have Tasker or Macrodroid watch an email inbox and send emails to that inbox with a format like email subject line = recipient phone number, email message body = SMS body. Then parse it through those automation apps and have it send the SMS for you.

I did something like this before and it worked decently well but I haven't had the best luck with getting Android apps to run stable for long periods of time without manual intervention. Not sure if it was battery optimization settings or what.

Re: Build an SMS Forwarder with Raspberry Pi Zero W and Waveshare SIM7000E Hat

#50

Post by fsagx »

newhouseb wrote: post #42
z92 wrote: post #15

If you can't purchase the GNSS HAT, use an old Android phone and install Termux on it. Then run some bash scripts on the phone that will do the job. The phone will communicate with your network over wifi, and replaces both the Raspberry PI and the HAT.

Also important to note that the Android approach is more likely to continue to work. In many places (certainly Manhattan, where I am), everything but LTE (and I gues 5G) has long been turned off such that GSM/Edge/UMTS/etc no longer work.

Cell site visualization tool featured on HN front page a few days ago shows thousands of 2g and 3g sites in NYC

https://alpercinar.com/open-cell-id/

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