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Working our way to Common Ground

Introduction

Below is a list of statements that I think we should walk down to find out where we are all together and where we have differences.

I think it will be much easier to find final wording if we can figure out what our agreements and differences are -- and then work on ways to address the differences.

I am seeing too many proposals that break something when trying to fix something else -- or that seem to fix the wrong thing. We won't get far that way.

I would suggest we just ask for objections to the following statements – and see how many we have consensus on – then work on the rest.

This will also help remind those less familiar with all of the aspects we are covering.

I suspect we can go through the first items pretty quickly and will find our differences down lower.


INSTRUCTIONS

Leave the statements as they are. Enter comments below them starting with * followed by 3 ~ characters to make a bullet with your name


GROUP 1 Statements

1) People who are DEAF OR HARD OF HEARING

  • should have reliable text conversation wherever people who speak and hear have reliable voice conversation, either directly or via AT.


2) People who are DEAF AND CAN SPEAK

  • should be able to use speech to send and text to receive communication (either simultanously or alternately), either directly or via AT.


3) People who are HARD OF HEARING

  • should be able to use speech to send and speech and text together to receive communication (either simultanously or alternately), either directly or via AT.


4) People who CAN HEAR BUT CANNOT SPEAK OR SPEAK CLEARLY

  • should be able to to use speech to receive and speech and text together to send communication (either simultanously or alternately), either directly or via AT.


5) People WITH DISABILITIES

  • should not have to pay more to make phone calls than people without disabilities. (Cost of AT hardware not included.)


GROUP 2 Statements


6) TTY (Baudot/TIA-825) is the only current method supported universally in the US for text conversation on the PSTN


7) In the evolving PUBLIC IP phone system – we want to use Text Data not TTY (or other ) audio tones to convey text.


8) IM is a valuable means of communication for everyone but particularly for people who are deaf.


9) IM is not real-time text. It is often near-realtime messaging. But it is messaging. And it can be delayed in addition to normal messaging delay (until ‘enter’).


10) Real-time conversation and IM are both valuable (to all communicators) but fill different needs.

  • IM is sometimes superior to real-time conversation.
  • Other times real-time conversation is superior.
  • IM is also used in place of real-time conversation when real-time conversation is not possible for some reason.


GROUP 3 Statements


11) Real-time text communication should be as reliable as real-time voice communication


12) Real-time text portion of a call should be as interoperable as real-time voice portion.


13) There is no (interoperability) need to specify which real-time Text Transport format is used WITHIN a SELF CONTAINED SYSTEM as long as the format is reliable and supported by all components in the system.

  • “Self-contained system” is a system where all of the terminals, routers and servers are manufactured by or controlled by a single entity.
  • A “Self-contained system” can include an Internet leg if both ends terminate inside the “Self contained system”.
  • Where the self contained system connects to other systems – (see below)


14) For two systems to interoperate (with real-time text) they must both support some protocol between them.


15) For a system to interoperate with an UNKNOWN system – it must support AT LEAST ONE format that is known to be SUPPORTED BY ALL OTHER SYSTEMS.


16) RFC-4103 is the most commonly supported real-time text format for SIP based IP Phone terminals connected directly to Foreign SIP Servers.

  • Foreign SIP server is a server that is not owned by the same entity that owns the terminal phone.


17) RFC-4103 and RFC-4351 are essentially identical except that

  • RFC-4103 (also called text/t140) sends text data packets on “text” channel that is separate from the audio data channel
  • RFC-4351 (also called audio/t140c) sends text data packets on the “audio” channel along with the audio packets. (But the text data is still sent as T140 data, not as audio tones.)
    • The use of a single channel is of benefit to PSTN gateways because it halves the number of ‘ports’ that must be created to handle a call and the voice and text are mixed on the PSTN side anyway
    • With RFC-4351 it is not possible to have simultaneous voice and text in one direction (which is required for IP Captioned Telephone) without creating/having an additional SSRC in the terminal device to keep the two data streams separate.
    • RFC-4351 is one of the multiple options that can be used in meeting TIA-1001
  • RFC-4351 has Intellectual Property claims against it from Cisco. RFC-4103 also has soft Cisco claims but RFC-4013 is a minor update of RFC-2793 which had no claims and RFC-4103 can be implemented without involving Cisco Intellectual Property.


18) VoIP Phones (terminals) (hardware and software) that have multiline displays ALREADY should display realtime text data that they receive.

  • Does NOT require that display be added
  • Does NOT require that whole display be used


19) VoIP Phones (terminals) (hardware and software) that have text input capability ALREADY should should allow realtime text data to be transmitted.

  • Does NOT require that a keyboard be added
  • Does NOT require any text input capability that is not already possible with the terminal


20) Where phones do not provide built in real-time text conversation capabilities, there should be a way to connect a device that does.

  • Either through the phone or in parallel
  • That has the same privileges as the phone
  • IF the phone is a public/shared phone – then connecting the text capable phone should not require an administrator.

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