Have you ever tried to identify the subscriber name that matched a telephone number? Of course you have. Dumb question. But securing the name, the carrier or the type of service — landline, cellular, VoIP or text-only — is not straightforward. You might dial a single number through Google Voice and get a non stop ring. Or call from a cell phone and get a recording that identifies it as a Verizon number that has been disconnected, changed or is no longer in service. Likewise, a phone number directory, may leave you confused.

If you send a text message to a device that receives these you get a confirmation that it was delivered. It’s possible that what you’ve tried calling is a text-only number. It may be active, but you wouldn’t necessarily discover that attempting a voice call. And it could be a number assigned to a service, not an individual subscriber. Still, you may find out something valuable, like I did when I interacted with this unknown number, which turned out to go a messaging program that sends automatic alerts from teachers and schools to students and parents when they register to receive them. Or to anyone who registers. In some cases, you’ll have to disclose an actual name of a student.