Error message

  • Deprecated function: implode(): Passing glue string after array is deprecated. Swap the parameters in drupal_get_feeds() (line 394 of /mnt/web020/b2/93/54000693/htdocs/realtimetext-org/public_html/includes/
  • Deprecated function: The each() function is deprecated. This message will be suppressed on further calls in menu_set_active_trail() (line 2394 of /mnt/web020/b2/93/54000693/htdocs/realtimetext-org/public_html/includes/

RTT in ITU standards

ITU Accessibility specific documents

Document Title Explanation Type Status
ITU-T Rec. V.18 Operational and Interworking Requirements for DCE:s Operating in the Text Telephone Mode Includes automatic interworking with most legacy text telephones. Modem transport Approved
ITU-T Rec. V.151 Procedures for end-to-end connection of analogue PSTN text telephones over an IP network utilizing text relay Text Telephony transit through IP.
References RFC4103
Gateway Approved
ITU-T Rec. F.703 Multimedia conversational services. Defines Text Telephony and Total Conversation services Service description Approved
ITU-T Rec. H.224 A real time control protocol for simplex applications using the H.221 LSD/HSD/HLP channel. Addition of client id=2 for T.140 text transport Transport Approved
ITU-T Rec. H.323 Annex G Text Conversation and Text SET. Defines T.140 text inclusion in H.323 IP Multimedia.
References RFC4103 Normatively
Call control Approved
ITU-T Rec.T.134 Text Chat Application Entity Application for text conversation in the T.120 data conferencing concept. Transport Approved
ITU-T Rec.  T.140 Protocol for multimedia application text conversation. Text conversation protocol for multimedia application. With amendment 1 (2000). Presentation level Approved
ITU-T Rec.T.140  - Addendum Marking of missing characters Replacement for characters  missing after transmission Presentation Approved
ITU-T H Series Supplement 1 Video Quality for sign language and lip reading Quality characteristics of video transmission of importance for sign language and lip-reading use. Requirement Approved
ITU-T Rec. H.248.2v2 Packages for fax, text and call discrimination Text telephony to text over IP gateway. Approved revision.
References RFC4103 normatively
Gateway Approved
ITU-T  FSTP.TACL Technical paper: Accessibility checklist General accessibility checklist for standardisers. Guideline Approved
ITU-T F.790 Telecommunications Accessibility Guidelines for Older Persons and Persons with Disabilities General accessibility guidelines Guideline Approved
ITU-T H.324 Annex L Updated draft for H.324 Annex on text conversation Addition or real-time text to the H.324 multimedia environment more reliable than earlier method Transport Approved

ITU general documents of accessibility interest

Standard Full Name of Standard explanation Type Status
ITU-T Rec. H.248.19 Controlled multimedia conferences Includes text Conference control protocol Approved
ITU-T Rec. F.700 Famework Recommendation for multimedia services, Annex A.3. Multimedia Framework, including real time text Service description Approved
ITU-T Rec. V.250 Serial asynchronous automatic dialling and control Contains modem control for V.18 Call control Approved
ITU-T Rec. V.8 Procedures for starting sessions of data transmission over the public switched telephone network Contains call function = text telephony Call control Approved
ITU-T Rec. V.8 bis Procedures for the identification and selection of common modes of operation between Data Circuit-terminating Equipments (DCEs) and between Data Terminal Equipments (DTEs) over the public switched telephone network Contains procedures for starting simultaneous voice and text in V.18. Call control Approved
ITU-T V.150.1 Modem transit over IP International  Recommendation for transport of Modem over IP Gateway Approved
ITU-T Rec.V.152 Procedures for supporting Voice Band Data over IP networks Usable for text telephony transit through IP networks Gateway Approved
ITU-T Rec.H.324 Terminal for low bit-rate multimedia communication Addition of data channel for T.140 text Multimedia system Approved
ITU-T Rec.  V.61 Analog simultaneous voice and data (permits Voice carry over with ASCII modems Possible to use under V.18 Modem transport Approved
ITU-T Rec.H.320 ISDN visual telephone systems and terminal equipment. Text conversation added Multimedia system Approved
ITU-T Rec. H.245 Control Protocol for Multimedia Communication Multimedia Control protocol, includes setup of text channels Call control Approved
ITU-T Y.1541
Network performance objectives for IP-based services
Requirement Approved
ITU-T Y.2000-series Suppl 1 Scope for next generation network, R1 Real time text and services for people with disabilities included Requirements Approved
ITU-T Y.2201 Requirements for next generation networks, R1 Accessibility features and services included Service Requirements Approved
ITU-T F.724 IP Videophone service description Real time text included Service description Approved
ITU-T F.733 Multimedia conference services Real time text included Service description Approved
ITU-T F.742 Service description and requirements for distance learning services Real time text included Service description Approved
ITU-T J.161 Audio and Video codec requirements and usage for the provision of bidirectional services over cable television networks using cable modems Cable TV network IP communication.
Text telephony and IP real-time text included.
References RFC4103
Technical requirements Approved

June 2007

ITU-T Y.2211 IMS based real-time conversational multimedia services over NGN Real time text included Requirements specification Approved

October 2007

ITU-T Y.NGN-et-tech Next Generation Networks - Emergency Telecommunications - Technical Considerations Real time text included Functional specification Draft