A VISION FOR RELAY
SERVICES AND
INTEROPERABILITY
Christian Vogler, PhD
Director, Technology Access
Program
Gallaudet University
Purpose of this talk
• What this talk is about
• A vision for extending the principle of functional
equivalence to global telecommunications
and new forms of telecommunications
• Technologies and standards issues
• What this talk is not about
• Policies needed to make this vision happen
• Legal frameworks
• Funding
Functional Equivalence
• An attempt at a definition:
Can deaf* people use telecommunication
services in the same unrestricted manner and
at the same costs as hearing people?
* “deaf” is meant to include deaf-blind, hard of hearing,
and people with speech disabilities, as well here
Call Scenarios
• What do hearing people take for granted in
telecommunications?
Call Scenario: Same Country
Alice (h)
Bob (h)
Call Scenario: International
Carl (h)
Alice (h)
Call Scenario: Roaming/Travel
Carl (h)
Alice (h)
Call Scenarios
• Let’s see what deaf people can do
• Need to consider both relay and point-to-point
• Why: principle of familiarity – should be able to
use common equipment for everyday and
emergency communications
• Remember: this is about technology
• Some countries have additional policy
restrictions
Deaf Call Scenario: Same Country
Dan (d)
TRS
Alice (h)
*
TRS = Telecommunications Relay System – here: all forms of relay
*Assumes integration of deaf user’s equipment into telephone
numbering system, a.k.a Ten-Digit-Numbering. (currently only US, and
partially UK)
Deaf Call Scenario: Same Country
Dan (d)
Emily (d)
Point-to-point: Works mostly, but not uniformly (and some
countries better than others)
Deaf Call Scenario: International (I)
Carl (h)
Dan (d)
TRS
*
Call is routed through relay in Dan’s country, in Dan’s language
*Assumes integration of deaf user’s equipment into telephone numbering system
Deaf Call Scenario: International (II)
Carl (h)
Dan (d)
TRS
*
Call is routed through relay in Carl’s country, in Carl’s language
*Does not work with integration into telephone numbering system
Deaf Call Scenario: International (III)
Emily (d)
Frank
(d)
Point-to-point: Does not work with same equipment as used
for relay calls
Call Scenario: Roaming/Travel
Carl (h)
TRS
Emily (d)
Call is routed through relay in Emily’s country, in Emily’s language
Works only if Emily can use her own equipment (and connection is not impeded or
impaired). Does not work if Emily borrows equipment in Carl’s country.
What is Missing?
• Voice calls (hearing side) are interoperable
• Global standards for landline, mobile, and
interconnected VoIP
• Relay calls (deaf side) are not interoperable
• Codecs and protocols (H.263, H.264, H.323, SIP,
proprietary, …)
• Call setup (i.e. how do I dial the call?)
• Lack of interoperability with mainstream VoIP
equipment (here: also includes video and text over
IP)
Codecs and protocols
• Need standards for codecs and protocols:
• Video, audio, text, images
• Must meet functional performance requirements for
communication
• E.g. sign language communication requires minimal frame
rate, resolution
• Recovery from network problems may be different from
current practice in mainstream VoIP
• Must work across environments (e.g. Internet, IMS,
and next-generation emergency)
• Should be compatible with mainstream equipment
(“may I borrow your videophone?”)
Call Setup
• Need standards for call setup:
• Connecting to relay provider and point to point
• Integration into the mainstream
telecommunications network (i.e., 10-digit
numbering or equivalent)
• Related policy question: who assigns – relay or
telecommunications carrier?
• Passing hearing party’s number to relay service
(i.e. I can dial and don’t have to fingerspell it)
• All this must work when roaming
Supplemental Services
• Standards for interacting with supplemental
services:
• Voicemail, Videomail (i.e., can deaf caller leave
a message, can hearing caller leave a
message, point-to-point messages?)
• Call alerting (i.e. how are deaf people notified of
an incoming call?)
• Others?
Looking Ahead: Teleconferencing
This is what currently works:
Bob (h)
Carl (h)
Audio bridge
Alice (h)
TRS
A
Dan (d)
TRS
B
Emily (d)
TRS
C
Frank
(d)
Looking Ahead: Teleconferencing
• Not functionally equivalent
• Hearing parties can hear one another
• Deaf parties cannot see one another
• Double translation – from Dan to TRS A, and from
TRS B/C to Emily/Frank
• Degrades accuracy and quality
• Introduces additional unacceptable lag
• Wasteful
• Availability of relay operators already cannot meet
demand
• Separate interpreters need to be paid, even if they
use the same language and communication
modality
Looking Ahead: Teleconferencing
This is what we need:
Alice (h)
Bob (h)
Carl (h)
Multimedia bridge
Dan (d)
Emily (d)
Frank
(d)
TRS
Looking ahead: Teleconferencing
• Relay services need to track emerging
standards for interoperable teleconferencing
systems
• Note: In the US, interoperable
teleconferencing systems are required by law
and recent FCC rules to be accessible under
the “Advanced Communication Services”
provision of the 21st Century Communications
and Video Accessibility Act
Areas that Need Attention
• Next-generation emergency services
• E.g. REACH 112, NG-9-1-1
• The switch to mobile telephony
• On LTE calls will be IP-based
• Unclear yet how relay services will interact with
the IP Multimedia Subsystem (IMS)
NENA motto:
“Any device, anytime, anywhere”
Let’s make this happen for relay services, too!
Acknowledgments
The contents of this presentation were
developed with funding from the National
Institute on Disability and Rehabilitation
Research, U.S. Department of Education,
grant number H133E090001 (RERC on
Telecommunications Access). However,
those contents do not necessarily represent
the policy of the Department of Education,
and you should not assume endorsement by
the Federal Government.
Questions?
Email: christian.vogler@gallaudet.edu
Web: http://tap.gallaudet.edu/
Related work
Vogler et al. Video Relay Service Practices and Policies
around the World. To appear in AEGIS workshop, Nov 2830, 2011.
Functional performance characteristics
• ITU-T H-series Recommendations – Supplement 1, 05/99
• FCC filing in CG Docket 10-51. Online:
http://fjallfoss.fcc.gov/ecfs/comment/view?id=6016375091