1. Paul E. Jones Cisco Systems, Inc.
Total Conversation through ITU-T Standards: Sign, Type, and Speak – You Decide
Paul E. Jones
Cisco Systems, Inc.

2. In the beginning, communication devices for the deaf opened a whole new world for the users of those devices.
They enabled people to communicate in ways that were never possible before.
Friends and family were able to carry on conversations over long distances, helping to maintain and even strengthen those relationships.
Without question, the introduction of the telecommunication devices for the deaf enriched everyone's lives.
But times change…

3. 15th Biennial TDI International Conference – Las Vegas, Nevada, USA
And so do the modes of communication!
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

4. It’s All About Total Conversation
The ITU-T is working on standards that bring about the convergence of
Voice telephony
Video telephony
Text telephony
These standards aim to enable what it calls “Total Conversation”
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

5. Defining the Multimedia Service
The ITU-T defined a series of service specifications and included text and video as components of the multimedia services (F.700 and F.703)
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

6. Popular Multimedia Systems
H.323 – Multimedia communication over packet-switched networks (Internet)
SIP – Session Initiation Protocol (Internet) (IETF)
H Multimedia communication over ISDN
H.324 – Multimedia communication over low bit-rate links (phone lines and mobile phones)
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

7. Problems with These Systems Identified
Multimedia systems had largely focused only on voice and video
There was a lack of support for text (or at least acceptable text)
Video support often did not take into consideration the needs of the deaf
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

8. 15th Biennial TDI International Conference – Las Vegas, Nevada, USA
More Standards
H Series Supplement 1 – Raised awareness about sign language and lip reading as it relates to video quality
T.140 – Standard to allow Unicode for textual conversation
IETF RFC 2793 defines the transport of T.140 over IP networks
Used by both H.323 and SIP systems
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

9. 15th Biennial TDI International Conference – Las Vegas, Nevada, USA
Integration
During the 1997 – 2000 timeframe, the ITU-T worked to add support for real-time text communication to the popular multimedia systems
Acceptable video support was more of an educational exercise… and the ITU-T has made an effort to educate!
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

10. 15th Biennial TDI International Conference – Las Vegas, Nevada, USA
…But Still Segregated
The video conferencing systems in use today are:
Largely used between two parties who have the same equipment
Not “tied into” the larger public communications networks
Further integration is required
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

11. 15th Biennial TDI International Conference – Las Vegas, Nevada, USA
The VoIP Revolution
Since the late 1990s, the communications industry has been heavily focused on “voice over IP” or “VoIP”
The basic idea is to simply use the Internet Protocol (IP) to carry voice, video, and data communications (sounds simple enough, huh?)
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

12. The VoIP Revolution (cont)
VoIP is still in its infancy, as compared to the mature public switched telephone network (PSTN)
Even so, a large number of telephone calls are carried over IP networks today
Unfortunately, multimedia communication services (the video and textual components) have been slower to “take off”
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

13. Bridging Two PSTN Networks over an IP NetworkGK GK
“Directory” Gatekeepers GK GK GK
Service Provider IP Core Network
H.323 PSTN Gateways
H.248 PSTN Gateways
MGC
MGC
“Text over IP” – V.toip
Scheduled for approval in January 2004 GK GK
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

14. 15th Biennial TDI International Conference – Las Vegas, Nevada, USA
ToIP Objectives
Allow for character-by-character text communication
Allow for simultaneous two-way conversation, along with voice and video (inherent limitations of the PSTN an obstacle)
Standardize on an international character set (Unicode)
Support all standard TTY device types defined in ITU-T V.18
Enable different device types to communicate through each other by using the gateways as “interworking” devices (see next slide)
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

15. Interworking TTY Types through the use of T.140
IP Network
V.21 Device
Baudot Device
T.140 bridges the gap
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

16. Building Bridges to the Enterprise and Residence
H.248 PSTN Gateways
MGC
“Directory” Gatekeepers
MGC GK GK GK
Residence GK GK
Service Provider IP Core Network GK GK GK GK
Enterprise
H.323 PSTN Gateways
Audio and Video Terminals and TTYs
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

17. 15th Biennial TDI International Conference – Las Vegas, Nevada, USA
Ultimate Goals
To allow any device to support the transmission of video and/or text signals
To allow a user on a PC connected to an IP network to chat with a user on a legacy PSTN TTY device
To improve communications with the widespread adoption of video
To allow a user with a wireless PDA to communicate with anybody in the world
To not require special tools for communications
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003

18. ITU-T Standards… Enable Video, Text, and Voice Communications.
So you can Sign, Type, or Speak.
You Decide!
15th Biennial TDI International Conference – Las Vegas, Nevada, USA
14-16 July 2003