The present invention relates generally to Voice over Internet Protocol (VoIP) networks, and more particularly to supporting a Telecommunication Device for the Deaf (TDD) in a VoIP network.
A telecommunication device for the deaf (TDD) (sometimes referred to as a Text Telephone (TTY or TT) or Telephone Text Device (TTD)) enables people who are hearing or speech impaired to communicate over the public switched telephone network (PSTN) using text messages. Typically, a user of the TDD device enters a desired text message into the TDD device, and the text message is transmitted over a network to another TDD device.
A user of a TDD device can also access network-based services, such as toll free services, supported by the PSTN. Toll free services typically offered to TDD device users over a telephone network often include a menu-based system offering a variety of options to choose from.
Many telephony networks are being migrated to Voice over Internet Protocol (VoIP) networks. This migration often causes the services previously available to TDD device users via traditional telephone services to no longer be available because these services are not traditionally provided by VoIP networks.
Therefore, there remains a need to provide network-based services to TDD devices when communicating over a VoIP network.