txt.att.net is returning MX records and those machines don't have port 444 open...

Wouldn't you want to be sending something like a SNPP message instead? It's a much less convoluted delivery process and is almost real-time (no queuing).

I guess it's been a decade or so since I've dealt with emergency services and paging...is SNPP even a thing anymore?

I looked at some old code I wrote (https://github.com/darkpixel/snppsend/blob/master/more-providers), and it doesn't look like snpp.attws.net exists.

-A

On Fri Jan 20, 2023, 02:12 PM GMT, William Herrin wrote:
On Thu, Jan 19, 2023 at 8:09 PM Dan Walters via NANOG <nanog@nanog.org> wrote:
Know this is a longshot, any chance anyone from the txt.att.net domain might be able to help us with what we believe is a blacklist block or possibly an outage?
We deal with 911 cad dispatching and is affecting first responders so looking to see if there is a faster way to resolution.

Hi Dan,

As I understand it, txt.att.net is a low-volume courtesy service not
intended for important communications. A paid service like Twilio can
handle production-grade SMS delivery.

Regards,
Bill Herrin

--
For hire. https://bill.herrin.us/resume/