A standard known as TTY has been in use by disabled phone users for quite some time, helping them to interact with others on the phone via both text to speech and speech to text, along with some units being capable of using Braille-enabled technology. When it comes to the world of wireless, TTY technology has gotten more convenient over the years, but can still be somewhat cumbersome, in some intances. TTY technology is also limited to a speed of 60 words per minute, which can be quite a limitation for long conversations, as well as those who type quickly or those who are used to much faster utilities, such as the Windows screen reader JAWs. This makes it far from optimal for a large number of use cases.
In place of the antiquated TTY standard, the FCC has adopted a new standard called real time text. This standard mimics voice communications - as text is typed, it shows up in real time on the other user's display. This allows for much faster and more effective communication for the disabled, as well as helpful use cases such as incomplete messages to 911 and a more natural conversational flow in normal communications. The proposal that outlines the network buildout to support such a technology also points to it being a good bit more reliable than the TTY technologies currently in use. Add in the fact that TTY technology requires a traditional phone network and, in some cases, a human operator, and it's only natural that as most communication shifts to IP-based networks, TTY is increasingly being phased out. FCC requirements eased up on TTY support last year, prompting many wireless carriers to quickly replace the aging tech.
The FCC's new ruling, which requires all carriers and networks to support real time text going forward, will help to integrate the remaining TTY technologies in use into modern networks, as well as helping them interface with their replacement, real time text. The FCC has set forth a list of essential functions, including things like voice calls and simultaneous voice and text communications, that most carriers will have to implement no later than December of 2017.