Cost 219ter

Presentation for the COST 219ter seminar on Standardisation and Legislation in Florence 8 March 2005.

Gunnar Hellström, Omnitor, Sweden
Member of ETSI STF 267 - DUST
gunnar.hellstrom@omnitor.se
+46 708 204 288

Abstract:

Telephony has always caused accessibility barriers. It has been in focus for COST 219 and its bis and ter successors. Already in 1993, a COST 219 seminar on legislation and standardisation was the direct source of inspiration to a range of standardisation activities in the International standardisation fora: ITU-T, IETF, 3GPP and ETSI.

The goal of many of these activities have been to add real time text to all mainstream call environments so that telecommunications can be made designed for all. Standardisation is a prerequisite for globally interoperable services. It started with text telephony in the analogue network, moved through the multimedia and mobile services where real time text was added and have been important for establishment of services including text. The Next Generation Network activities in the standard bodies call for raising the activity level in accessible conversation service standardisation and make sure that the services are made accessible from the beginning. There is currently an activity in ETSI, called STF 267 DUST, that summarises text requirements and solutions in a guide and give initial input to NGN accessible services, but stronger continuous forces are needed. It would be excellent if this presentation in the COST 219 ter seminar on standardisation and legislation can be the source of inspiration for such activities leading to NGN services becoming the first generation telecom services to be fully accessible from its creation.

Gunnar Hellström, has participated as author, editor or rapporteur in many of the activites in the accessible conversational service area on behalf of actors with responsibility for the area. Gunnar is founder of Omnitor, a product developing and service provider in this field.


Accessible conversation services - a COST219 topic

A favourite topic of COST 219 and its bis and ter successors has been argumentation for design for all in conversational services. The apparent solution has been to add media to telephony, so that text telephony and total conversation are created. Text telephony offers real time text and voice communication. Total conversation offers real time video, text and voice communication. Both services offer important accessibility increase over voice telephony, and it would be an obvious goal for all accessibility actors to make sure that these services gets widely used instead of the inaccessible voice telephony over the coming years.

User benefits of real time conversation in video, text and voice

Many users benefit from having access to real time text and video in the call. The most commonly known users are deaf, hard-of-hearing, deaf-blind and speech-impaired persons. Also anybody in a noisy location or a place that requires silence or with a task that requires exactness benefit from having a real time text medium available. By having all three media available, it is easy for a user to adapt to the situation for the moment and use the media that the two users can handle. Relay services can come in and translate between media, e.g. between sign language in the video channel and speech in the voice channel, or between text and voice.

COST219 seminar in Budapest - a kick-off for standardisation

Activities in COST 219 in the seminar on standardisation and legislation in Budapest, 1993 gave inspiration and information to a series of activities in regional and international standards groups with the goal to bring real time text into mainstream telecommunication standards and create a base for interoperability on the same level as the voice medium is supported by global interoperability.

The fragmentation of the analogue text telephone situation was a hot topic in both COST 219 and COST 220. The Budapest seminar was an important source of inspiration to standardise. Since then, standardisation of this topic has been performed in European and International standard bodies so that we now have a comprehensive set of standards. The main topic has been to add the real time text medium to various call environments.

Standardisation is a prerequisite for interoperability. Interoperability is required for usability.

Requirement specification in ETSI

It all started in the European Telecommunication Standards Institute ETSI and its Human Factors group HF, where a report on user requirements in text communication was created to have a firm base to return to

ITU, going from text telephony to multi-media

A harmonizing standard, V.18, for all textphones in the analogue network was created in the International Telecommunication Union, ITU. It is now the base for an overlay network evening out the differences between textphones in UK. The standard is also used in products that can be used for calls with the textphones from various types of the fragmented world of text telephones, so its users are freed from the famous old incompatibilities.


A common presentation level for text conversation

A common presentation level standard, T.140, was also created in the ITU, forming a high level base for interoperability and usability, by introducing the use of the internationally usable character set Unicode for text conversation. This standard takes up and documents an important feature of the old text telephones that needs to be maintained in new environments. Each character should be transmitted as soon as it has been entered, in order to mainstream a live contact between the parties in a call. This is equivalent to how audio and video is transmitted in a live call. If this principle is not applied to text, there is an apparent risk for misunderstandings, double postings and less efficient dialogues.

Do not mistake real time text for messaging

Just as with voice mail and stored video messages, text messaging is a good complement to real time services. The real time text users need to be provided with a real time interactive text based service, with the same reason as no hearing user would sacrifice the real time voice call and be satisfied with voice mail only,

Service descriptions for reference

Service descriptions for text telephony and total conversation services were also created in the ITU. They capture user requirements and set up goals for fulfilling these requirements with the services. These descriptions form an important top level reference for all technologies far beyond the domain of ITU technical recommendations.

Many technical transport specifications for text

Many real time multimedia communication protocols are created by the ITU. For each network environment one communication protocol collection is needed, and a corresponding specification about how to set up and transport real time text in that environment. During an hectic period of accessibility standardisation, descriptions of T.140 text transport were created for all environments.

IP based services, started 1998, the hot topic today

In the process of adding text to the IP based multimedia standard ITU-T H.323, there was a need to go to the Internet Engineering Task Force IETF to standardise the packetisation of text. This activity led to the creation of standards for IP text conversation usable in the two dominating IP telephony environments ITU H.323 and IRTF SIP. With the work with text in SIP, a rich range of opportunities have opened that include smart connection of relay services. The exploitation has just begun, and many situations that are felt cumbersome today can be smooth tomorrow by consistent application of the standards.

Mobile text - wherever voice is carried

When US legislation required text conversation services in the mobile networks, a forceful ction was performed in the mobile standardisation consortium 3GPP, leading to text support defined for all three call environments in GSM and UMTS mobile systems. They built upon the standards created in ITU and IETF.

Old text telephony is at risk

One recent topic for ITU standardisation in the field is specification of transport of analogue text telephony through IP transit networks. IP technologies are taken into account for transmission of old telephone network tones to an increasing degree. The first methods for such transmission was mainly focussed on voice transmission. If used for text transmission between analogue textphones, these methods tend to introduce a high degree of character errors and varying quality on text calls. So, the new transmission standards, taking text telephony into account are needed to protect the analogue text users from deteriorating service quality. A question is hanging over this activity: Will the standards be implemented in time, or will the remaining users of analogue text telephony need to give up their service because of reliability problems, and move over to IP based services? And will the IP based replacements be harmonized and give global interoperability?

Back to ETSI for writing the DUST guide

Now, the initiative is also back to ETSI, where a Specialist Task Force, STF 267, is currently developing a guide for Duplex Universal Speech and Text, DUST, focussing on user requirements and implementation advice for IP networks of mainstream text telephony and total conversation. The goal is to refer to available standards, and especially the SIP related specifications are valuable for the work with DUST.

Next Generation Network - a fresh opportunity to design for all

Next Generation Network, NGN, is a hot topic in ETSI as well as in ITU. The goal is to make user experience and service availability similar regardless of what physical network you happen to connect to for the moment. The intention is a convergence between various networks. Being a fresh activity, starting with service definitions, it is very important to get an opportunity to apply design for all principles now, when NGN is created. Therefore, one important task for DUST is to give input to creation of NGN definitions. However, the DUST activities have limited resources, and is soon completed. NGN has just gained momentum and will continue with service definitions and lower level specifications. Therefore there is an urgent need to make sure that accessibility aspects are taken into account from the beginning and that the input that DUST has made is followed up and brought into completed specifications of accessible mainstream service features.

Back in COST 219 ter - kickoff to forceful deployment

The topic of accessible conversational services is now on the agenda of a COST 219 ter seminar on the theme of legislation and standardisation. 12 years after the seminar in Budapest. We can look back on successful standardisation, with real time text specifications available for all standardised environments where there is a speech service available. The combination with video is especially valued by the users, and the SIP based variant in IP networks is the variant most talked about, that seems to get momentum to play the role as a reference point for the future.

Still, the struggle to get accessible services automatically included by mainstream developers is not over. Even with the success in standardisation, the availability in interoperable implementations is not overwhelming. If the Budapest seminar serviced as inspiration for standardisation, the Florence seminar can have an important role to serve to inspire to forceful implementation of globally interoperable accessible conversation services providing video, text and voice to all users.

The standards have been created in good international collaboration among engineers and accessibility actors. Resources have been put in by accessibility institutes, telecom agencies, telecom manufacturers and operators. The result of the standardisation activities is very good. The take-up in products and services could be far better. Publicity, policy-making and marketing accessible services still lag behind in volume.

Good signs of interest from the community can result in global interoperability

Good signs are that the topic is up for discussion in the European Commission related groups TCAM for terminals and INCOM for services. These groups discuss application of directives, and they are trying to formulate actions, or policies that could stimulate the actors to deliver accessible services. The existing standards form a good background for these discussions. Encouraging mechanisms can possibly be created that will increase the provision of globally interoperable accessible services.

Information links

ETSI STF 267 DUST, creates a guide EG 202 230. See portal.etsi.org/stfs/hf/STF267.asp

ITU-T has the actions concentrated to SG 16, Question 26, Accessibility to Multimedia. www.itu.int

In IETF, the main groups are avt and sipping. see www.ietf.org

For a description of this area, please see the presentation " Total Conversation; Increased usability of conversational services in mobile and fixed networks". www.etsi.org/cce/proceedings/4_5.htm

A list of related documents and their current status in March 2005, is found in appendix A (NB: not available here).

 

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