47 CFR § 67.1 - Definitions.

---
identifier: "/us/cfr/t47/s67.1"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "47 CFR § 67.1 - Definitions."
title_number: 47
title_name: "Telecommunication"
section_number: "67.1"
section_name: "Definitions."
chapter_name: "FEDERAL COMMUNICATIONS COMMISSION"
subchapter_number: "B"
subchapter_name: "COMMON CARRIER SERVICES"
part_number: "67"
part_name: "REAL-TIME TEXT"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "47 U.S.C. 151-154, 225, 251, 255, 301, 303, 307, 309, 316, 615c, 616, 617."
regulatory_source: "82 FR 7707, Jan. 23, 2017, unless otherwise noted."
cfr_part: "67"
---


# 67.1 Definitions.

(a) *Authorized end user device* means a handset or other end user device that is authorized by the provider of a covered service for use with that service and is able to send, receive, and display text.

(b) *CMRS provider* means a CMRS provider as defined in § 20.18(c) of this chapter.

(c) *Covered service* means a service that meets accessibility requirements by supporting RTT pursuant to part 6, 7, 14, 20, or 64 of this chapter.

(d) *RFC 4103* means IETF's Request for Comments (RFC) 4103 (incorporated by reference, *see* § 67.3 of this part).

(e) *RFC 4103-conforming service or user device* means a covered service or authorized end user device that enables initiation, sending, transmission, reception, and display of RTT communications in conformity with RFC 4103.

(f) *RFC 4103-TTY gateway* means a gateway that is able to reliably and accurately transcode communications between (1) RFC 4103-conforming services and devices and (2) circuit-switched networks that support communications between TTYs.

(g) *Real-time text (RTT)* or *RTT communications* means text communications that are transmitted over Internet Protocol (IP) networks immediately as they are created, *e.g.,* on a character-by-character basis.

(h) *Support RTT* or *support RTT communications* means to enable users to initiate, send, transmit, receive, and display RTT communications in accordance with the applicable provisions of this part.