In the WTF category... A SMS server crashed on Valentine's day, is now back online, and 150 000+ delayed SMS were received... two days ago

So if you received “I wanna f— you like an animal” from your ex, I guess it’s too late now…


Maybe an int-overflow or similar.

Happens at times. As a student in computer science, I got to wonder why there are no watchdog in place to kick servers like this back into gear faster.

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Yeah, faster than nine months :open_mouth:
I mean, what the hell. Receiving SMS from dead people, come on.

Edit: Also, TIL you can send SMS and the message can go through a random sub-contractors’ server. Now I know why some people don’t trust phone numbers for 2FA…

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…That is how the Internet works though?

The idea is (was) that everyone handles as much traffic as they produce, so no fees for anyone.

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I honestly don’t even know exactly how SMS works, or if it even is part of the internet itself, etc etc…

I know about Amazon web services and the cloud and “there is no cloud: it’s just someone else’s computer”, etc, just never thought about Amazon or, in that case, Syniverse, could handle SMS messages… for both T-Mobile, Sprint, AT&T and Verizon even.

Essentially like any wireless transmission in the mobile device to antenna bank.

  1. Request connection
  2. Identify
  3. Target
  4. Data
    For simplicity, I cut the acknowledgements. Full graph looks like this:

As nearly everything uses this handy thing called THE INTERNET, everything is now X-over-IP (Voice over IP = VOIP, TV over IP =IPTV ←wierd, etc.). Let me explain further:

Layer What is going on Form
7 - Application Data is packaged by the application SMS
6 - Presentation SMS is data, it needs to be repacked to be useful for computers SMS → Data
5 - Session The session is opened with the server (basically what the cellphone did with the cell tower earlier, but over internet)
4 - Transport Data is packaged and sent away Data → Packages
3 - Network [First layer not on your device] Packages are routed to target area. (This is what you need a router for :slightly_smiling_face:)
2 - Data Link Layer 2 magic
1 - Physical A cable and antenna, electrons or photons are realy moving your data!

This stuff now goes through layer 1 to 3 multiple times until the server called from session layer is reached.
That Server goes up all the layers into Application layer again, does SMS-over-IP routing, establishes a session with the cell tower near the target and sends the SMS onward, through all the layers 7 layers, multiple times through 1 to 3…

As an image:

What went wrong was probably on Layer 7 in the Server, the safe-mode was to store the recieved SMS until a downlink to cell towers near the target devices could be established. (my guess)

Amazon, or specifically AWS, sells data handling in any form. Everything is “just data”

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Wow, that’s an explanation. Haha, thanks!

That’s… a bit scary. And yeah, IPTV sounds weird. Reminds me of a guy who named his wifi “IPfreely”.