With federal inmate texting, messages are relayed using the federal Corrlinks/TRULINCS equipment

https://prisontexting404.clearhavendigest.com/posts/how-to-pick-the-best-federal-inmate-text-app-for-secure-communication

With federal inmate texting, messages are relayed by using the federal Corrlinks/TRULINCS method, and replies can go back to the outdoor user as commonplace text messages.