IT & MCIS
DEFINITION
OF STANDARD:
Video conferencing
allows individual at separate locations to see and hear each other, conduct
meetings, and work together using interactive video and audio technology.
Images of documents can also be exchanged, and desktop computers can be
used to share files or let participants work together on documents or
projects. The Kentucky Tele-Linking
Network (KTLN) provides an infrastructure of sites utilizing compressed
video technology for interactive distance learning and meeting sessions.
Satellite conferencing offers the ability to broadcast to many downlink
sites with audio response.
FUTURE
DIRECTION:
Desktop hardware requirements change as the software applications become
more sophisticated and the underlying operating system continue to add
features and enhancements. Hardware systems recommendations are reviewed
twice a year. As products become available to support new applications
or resolve known problems, the supported list will be revised.
REVISION
DATE: July 1,
2003
EFFECTIVE DATE:
December 11, 2001
REVISION DATE: 6 months
RESPONSIBLE
CONTACT:
Andy Spears aspears@email.uky.edu
Recommended
Standard(s):
ITU-T Standards Supported:
H.320, G.711, G.722, G.728, H.221, H.261,
Video
Conferencing
Algorithms and resolutions (pixels x lines):
ITU-T H.261 (P x 64)
352 x 288 (FCIF
176 x 144 (QCIF)
Frame rate: 30 frames per second
Monitor outputs
Main: S-Video
Local view/PC: S-Video
Camera inputs
S-Video and Composite
Video format: NTSC
Broadcast standards: NTSC
Audio Conferencing
True omnidirectional pickup; automatic microphone level adjustment; multimedia
AVI playback.
In-band coding
rates:
ITU-T G.722:
48/56/64 KBPS, 50 Hz-7 kHz
ITU-T G.728:
16 KBPS, 50 Hz-3.4 kHz
ITU-T G.711:
64 KBPS, 50 Hz-3.4 kHz (µLaw/ALaw)
Operation
Full-duplex, adaptive acoustic echo canceling
Communications
Protocols
HDLC
ITU-T H.221
Interfaces
DDM associated dialing
V.35/RS449 x2
RS366/Direct Connect
Transmission rates
384 KBPS or fractional T-1 is the predominant transmission for KTLN
Recommended Product(s):
VTEL Video Conferencing Models:
Galaxy
SmartLink MCS
Polycom Video Conferencing Models:
View Station Fx
VS 4000
See 3450 Desktop Video Conferencing.
Video Display
Monitors and projection televisions are used in interactive television
classrooms. The audiovisual standard for monitor size per viewer is one
diagonal inch of screen per viewer. Since students participating in courses
delivered by interactive video must often view very detailed visual information;
the current standard is from 1:1.3 to 1:1.6 inches per viewer. Example:
A classroom seating 40 students will have a projection television with
a screen that measures 52 inches diagonally, a ratio of 1:1.3 diagonal
inches per viewer.
Audio
Classrooms are equipped with one microphone per two students. A classroom
seating 40 students would include 20 push-to-talk microphones. Although
voice activated microphones were installed in all of the early UK classrooms
distractions caused by microphones activating from extraneous sounds mandated
a change to the current standard, i.e., push-to-talk microphones.
Cameras
Large classrooms (i.e., 30+ students) utilize Parkervision cameras. The
instructor camera incorporates an automated system that causes the camera
to follow the instructor around the classroom, keeping the instructor
correctly framed and in focus. The Parkervision system also includes a
wireless microphone for the instructor. The Parkervision student camera
is connected to the push-to-talk microphones and can zoom in on a student
when the microphone is activated; giving audiences at the remote sites
a better view of the student.
Smaller classrooms (i.e., 10 Š 30 students) and conference rooms are equipped with cameras featuring remote pan, tilt, and focus capabilities. These cameras do not follow presenters nor zoom to students when microphones are activated.
Classroom control
All classrooms utilize VTelÕs proprietary PenPal Graphics Tablet to control
the elements in the classroom (i.e., cameras, audio, VCRs, laptop computers,
and slide-to-video converters). As interactive television equipment from
other manufactures is installed, new classroom control devices will be
incorporated.
Connectivity
Classrooms located in Lexington are connected to the network through 4-wire
circuits utilizing CSU/DSUs (Channel Service Unit/Data Service Unit).
Classrooms at remote locations are connected to Lexington through T-1 digital telephone lines. Circuits are connected to NewBridge technology in Parking Structure 2. A connection for each room is made to First Virtual CorporationÕs V-Room technology. The V-Room is connected to the Kentucky TeleLinking Network (KTLN).
Alternative connectivity is available through Integrated Services Digital Network (ISDN) technology. ISDN provides digital telephone service into the public telephone network.
Maintenance
Maintenance contracts with the vendor that supplies the interactive television
technology are purchased for each classroom. The University of Kentucky
does not have personnel certified to maintain this equipment. The standard
for maintenance is GTE Service Level A, on-site maintenance with maximum
repair/replacement time of twenty-four (24) hours for service item being
fully functional.
Scheduling The primary utilization of the University of Kentucky Interactive Television Network is to deliver credit programs and classes. When the network is not scheduled for classes, the system is available to deliver non-credit activities such as continuing education and administrative meetings. Credit courses have first priority.
Dates have been established for scheduling non-credit activities.
- Non-Credit activities for the Spring Semester can be scheduled on or after September 15 of the preceding year.
- Non-Credit activities for the Summer Sessions can be scheduled on or after December 1 of the preceding year.
- Non-Credit activities for the Fall Semester can be scheduled on or after March 15 of the current year.
Scheduling of credit classes can be found under the Standards for Distance Learning Programs.
Justification:
The KTLN is based on a product standard deployed statewide for distance
learning and government meetings. Over
200 KTLN rooms exist in Kentucky, which MOST utilize VTEL video conferencing
technology. A Verizon state price contract and website for product information,
pricing and support is available at http://www.ktln.com
Technical Considerations:
VTEL and Polycom use ITU standards for the video and audio transmissions.
Because of LAN bandwidth considerations, departments considering desktop
video equipment should consider using Integrated Services Digital Network
(ISDN) with a 384 Kbps connection. ISDN requires an ISDN modem for dialup
networking at 384 Kbps.
H.323 is the evolving standard for video transport over the LAN/WAN using IP. The primary barriers today for H.323 use in the state is infrastructure capacity, bandwidth allocation and quality of service. Early adoption and deployment of H.323 has inherent risks, most importantly interoperability issues because over 95% of the state's video conferencing equipment use the H.320 standard. As technical and business issues are resolved, it is expected that H.320 and H.323 will coexist in state government and education. Because of various technical issues that remain unresolved, departments should not deploy H.323 video transport without prior approval from the Department of Information Technology.
The majority of VTEL equipment installed in the state is on the MediaMax platform or ESA-based platform, which operates under Windows 95 OS.