2000s (2)
IP telephony grows
widely variable reliability of analog TTY transmission
no implementations of standardized text conversation
Consumers moving away from PSTN where broadband is available, possibly faster than hearing population (no data available)
But some are stuck with TTY due to lack of service (e.g. rural), economics
Also older people need simplicity of TTY
Standards work continues on text conversation in IP
reliability and interoperability not assured by these standards, even if implemented.
TTY still the only interface to 911