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Welcome Any to Any Connectivity For Everyone? (Communication Hub Model) Len Bytheway Australian Communication Exchange 1
If it ain’t broke…? 2 There are tens of thousands of textphones (TTYs) used in Australia and hundreds of thousands used in the USA they work and people love them… why change?
About the TTY 3 • TTYs were developed from old teletype machines discarded (EOLed) in the 1960 s. They operate: • 50 bits/sec (45. 45 in the USA) • Use 5 bit Baudot code (Dev’t 1874) • No Carrier • Half Duplex • Some can be acoustically coupled • They are basic, cheap and work consistently
TTY Standards? • World has adopted multiple textphone standards • European Deaf Telephone (EDT) • Minitel (V. 23 based systems x 3) • DTMF (phone dial tones) • ASCII (V. 21, Bell 103 @300 baud) • Baudot TTYs (50 & 45. 45 baud) • Australia is the only country in the world currently “standardised” on 50 baud Baudot TTYs 4
Problems with TTY 5 • Lack of TTY access via mobile networks (esp. to text Emergency Call Service 106) • Deaf people have ‘adopted’ mobile phone technology SMS (reliability issues)
Problems with TTY 6 • Emerging Technologies incompatible with TTYs • Wireless local loop (WLL) & Internet telephony as standard telephone services (STS) • NGN & IP services?
The Future Textphones? 7 • Availability of V. 18 standard (ITU) brings all text telephones together • Development for text & video standards for Internet (using H. 323 video standard, eg Microsoft Net. Meeting) • SIP, ENUM and text access?
Real Issue 8 • Large installed base of TTYs • TTYs dispersed, can’t be located to swap out • Vital services on baudot infrastructure (health, welfare & emergency services, education, social, family…) • Let’s not confuse the Form Factor (TTY) with the underlying Protocol (Baudot)
Real Question How can we migrate to digital technologies and phase out legacy technologies? without disruption or loss of services 9
Text. Direct (UK) Dials 18001 nnnn Voice Network 18001 routes to TXD V. 18 modems Dials nnnn 10
IP Relay (USA) V. 18 Internet Access Directory Server Voice Network Relay Service 11
Proposal for Australia NGN Reqs? IP networks Video Relay Services V. 18 and other bridges Access Directory Server “Communications Hub” Switched networks 12
Not “Out of the Box” 13 • Do it once for all Australians on any network • Modular - parts installed as needed • The hub is “organic” - growing with technology • Protects against future technology changes • Allows people to take up the new, but stay connected to the old.
Beyond Technology • On solution does not work for all - people need choices • Use mainstream solution where possible • More than ever we will need: • Awareness • Training • Support • New challenges to assure privacy 14
The Way Forward? • Stakeholder consultation and buy-in: • People with Disabilities • Broader community • Telco Industry • Legislators/Regulators • Refine the model • ACIF Forum to discuss options - early 2002 15
Thank You Questions? www. aceinfo. net. au 16