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A
ACAP
Advanced Application Platform specified by ATSC. ACAP is based on the
GEM and DASE standards and includes some additional functionality from
OCAP.
AIT
Application Information Table. Provides information about the activation
state of bound OCAP applications.
Amplitude Modulation
A process of transmitting radio frequency signals by varying the amplitude.
This process is used for radio, television and fax.
ANSI
American National Standards Institute - a standards body of the United States.
API
Application Programming Interface.
ARIB
Association of Radio Industries and Businesses. Japanese iTV middleware
standard.
ATE
Automatic Testing Environment. This is a server and software architecture
used by CableLabs and other organisations for the delivery of conformance
tests to receivers under test ("RUTs").
ATSC
Advanced Television Systems Committee formed to establish a set of technical
standards for broadcasting in High Definition (HDTV). UniSoft is currently
a member of ATSC.
B
Bandwidth
Bandwidth: The data rate of a digital signal which is commonly stated
in units of bits-per-second (bps).
Bound Application
Applications (OCAP and MHP usually) which are associated with a particular
TV channel (service). When the viewer changes channel, the application
bound to the previous channel is terminated.
C
CableCARD
Removable security card for digital cable terminals, as defined by the
OpenCable project.
Certificate File
A digitally signed file containing the public key used in digital signature
verification and details of the owner and issuer of that public key.
CMTS
Cable Modem Termination System. A router which interfaces between Ethernet
networks and RF network connections to cable modems.
D
DAC
Digital Access Controller. Cable headend control system from Motorola used by
many of the US MSOs and cable operators.
DCD
Downstream Channel Descriptor.
A DSG address table used within the DOCSIS MAC Management Message to manage
the DSG Tunnel. DCDs sent out by a CMTS can be detected by an OCAP receiver and
provide the receiver with sufficient information to receive data from
the DSG tunnel. XAITs can be transmitted down DSG broadcast tunnels.
Digest
A message digest is a one way function that generates a statistically unique
sample for a set of input data.
DNCS
Digital Network Control System, a product of Scientific-Atlanta, Inc.
The Digital Broadband Delivery System (DBDS)
receives analog and digital services from a variety of sources including
satelitte and securely transports the services to the subscribers home.
Services supported by the DBDS are controlled by the DNCS.
DSG
DOCSIS Set-Top Gateway.
DSG Address Table
The collection of DSG Rules and DSG Classifiers contained within the DCD
message.
DVB
Digital Video Broadcasting program within the European Broadcasting
Union (EBU). DVB specified the MHP middleware standard.
E
EBIF
ETV Binary Interchange Format.
EISS
ETV Integrated Signaling Stream - an MPEG elementary stream which carries
media timeline messages, stream events and EISS tables for an ETV application.
ETV
Enhanced Television, a specification by CableLabs which allows deployment
of interactive content on "thin-clients" such as the Motorola DCT 2000
(with over 15M platforms deployed) and Scientific Atlanta Explorer 2000
as well as OpenCable (OCAP) host devices.
ETSI
The European Telecommunications Standards Institute, a recognized standards
body located in Southern France.
F
Forward Channel
The direction of radio frequency (RF) signal flow away from the headend
toward the end user; equivalent to downstream.
G
GEM
Globally Executable MHP. A terminal specification based on MHP that enables
applications to interoperate across OCAP, MHP and other GEM based platforms.
H
Headend
The control centre of a cable television system, where
incoming signals are amplified, converted, processed, and combined into a
common cable, along with any origination cable-casting, for transmission to
the home.
Host Device
Set-top-box or receiver containing and executing the OpenCable Application
Platform implementation. It is also host to the CableCARD device.
I
iTV
Interactive TV usually means the viewer using the remote control to "interact"
with the TV to change the available video, audio and any graphics in some way.
These changes are typically made by an interactive software application
running in the set-top-box or TV.
J
JVM
Java Virtual Machine.
K
Key Pair
A public and private key pair. Information is encrypted using
a private key and others can use the corresponding public key to decrypt.
If decryption is successful, you have a high degree of confidence the
transmitted information originated from the registered holder of the private
key.
Kit Files
With respects to SoftOC, Kit Files consist of transport packets and
DSM-CC modules plus an XML kit-control file. The control file describes
how to multiplex these parts at the section level in order to achieve
user defined MPEG /DVB/DSM-CC/OCAP table repetition rates.
L
Linux
Multi-user operating system used by many OCAP receiver manufacturers
to execute their OCAP middleware implementations.
M
MHP
Multimedia Home Platform specification produced by DVB.
Model
With respects to TSBroadcaster systems, a model means a snapshot
capture of a current TSBroadcaster configuration which is placed in a ZIP
file. The model includes all applications which have been registered
with TSBroadcaster, play-out schedules and configuration data. Models can
be uploaded to, and download from, a running TSBroadcaster system.
Middleware
In the context of interactive TV, the software which runs on a TV receiver
which is layer between the operating system and the applications. Most
middleware which are open standards are based on Java.
MMI
Man Machine Interface is another term for User Interface.
With respect to OCAP, MMI specifies the protocol used over the
CableCARD/Host interface to enable the CableCARD device to display
messages on the television display.
MPEG
Moving Picture Experts Group. A group which develops standards for
digital, compressed moving pictures and associated audio.
MPEG-2 is a video compression standard commonly used by cable television
operators.
MSO
Multiple System Operator. A term for US cable companies that operate
multiple cable systems. Time Warner Cable and Comcast are MSOs.
MTC
MHP Test Consortium.
MUG
MHP Umbrella Group, which sets specifications for the Globally Executable MHP,
variations to the MHP specification to account for regional broadcast
environments.
N
N+1 Redundancy
A mechanism for failure recovery in computer architectures which consist
of multiple server systems. An additional server,
known as a "hot spare", is included which can act
as a replacement if any one of N systems fail.
Native Application
Typically an application which is written for the operating system of
a receiver (set-top-box) rather than the middleware standard that may
also be running on the receiver. ETV User Agents are implemented as
native applications.
O
Object Carousel
A format for the transmission of data and events to the terminal.
These formats are defined in ISO/13818-6 standard. Their usage is defined in a
profile contained in DVB-MHP Specification Annex B. Essentially these
definitions provide a way of transmitting a Unix-like file system down a
broadcast channel. TSBroadcaster is capable of generating
object carousel.
OCAP
OpenCable Application Platform, the US cable industry's middleware standard
specified by CableLabs. Also known as the "OpenCable Platform". OCAP is Java
based.
OCAP ATE
OCAP Automatic Test Environment. This is the OCAP version of the
ATE (see "ATE" above) which is used by CableLabs to
deliver the OCAP conformance tests to receivers under test.
OCAP ATE Host
Host server system for the OCAP Automatic Test Environment (ATE).
OpenCable
A project established by CableLabs, to standardize a cable network interface
and to build a retail market for digital cable terminals.
Out-of-Band (OOB)
An out-of-band is a channel which is the combination of the forward and reverse
OOB channels. The OOB channel provides an IP-based
communication channel between a cable network and the set-top-box.
Out-Of-Band-Forward-Data-Channel (OOB-FDC).
The portion of the cable RF range that is used to deliver system or service
information to a receiver. Its frequency range is generally 70-130 Mz.
Out-Of-Band-Reverse-Data-Channel (OOB-RDC).
The portion of the cable RF range that is used to deliver data from the home
receiver to the headend. Its frequency range is 5-40 Mz.
P
PID
Packet Identifier. A unique integer value used to identify elementary streams
of a program in an MPEG-2 transport stream.
PMT
Program Map Table. An MPEG-2 table which provides data and location on
all TV services in the transport stream.
Q
QPSK
Quadature Phase-Shift Keying - A digital modulation technique which changes
the phase of the reference signal or carrier wave using four phases.
US cable headends often use QPSK modulation for the out-of-band
channel.
R
RCA
Root Certificate Authority.
Return Channel
A data path that goes from the subscriber to the cable headend. Also known
as Upstream, Reverse Path or Return Path.
RUT
Receiver, or terminal, Under Test, a term used often with respect to the
MHP and/or OCAP ATE.
S
SI
Service Information. Information that describes the TV services available on
the network. OCAP service information is defined by the SCTE 65 standard.
Signature File
A file containing a unique code generated by applying a private key against
a known, reproducible, set of data. The converse operation of applying the
corresponding public key against the unique code will reconstruct the original
data.
SoftOC
DSM-CC object carousel generator and transport stream encoder used by the MHP
and OCAP ATEs.
T
Teletext
Broadcast service which uses several otherwise unused scanning lines
(vertical blanking intervals) between frames of TV pictures to transmit
information to receiving TVs. This service has been very popular in the
United Kingdom for many years.
Tru2way
is the interactive TV standard for use cable systems. It replaces the term
"OpenCable Platform" and is CableLabs' brand for the OCAP middleware standard.
TSBroadcaster
An encoding solution and DSM-CC carousel generator which handles automatic
and scheduled playout of OCAP, ETV and MHP applications.
TSDeveloper
A multi-user environment for developing and testing ETV and OCAP applications.
TSMux
Multiplexor and play-out software used by the OCAP ATE to broadcast OCAP test
cases through ASI output.
TSPlayer
An MPEG-2 transport stream player used by TSBroadcaster for output via
ASI or Gigabit Ethernet.
U
Unbound Application
An OCAP application which is not bound to a particular service. It is present
across all of the TV channels. OCAP EPGs and the Monitor Applicationa are
unbound.
User Agent
Usually used in the context of ETV, a User Agent is native application which
interprets EBIF binary code and renders images on the TV screen appropriately.
V
VOD
Video on Demand. A feature which allows TV viewers select (usually from the
program guide) a movie or program to be played almost immediately. Usually
VOD services are provided by VOD servers located in the cable company's
headend.
W
W3C
W3C Consortium - An organization formed to develop common protocols to ensure
interoperability and promote the World Wide Web.
X
XAIT
eXtended Applicaton Information Table. An enhanced version of the
AIT used to signal unbound OCAP applications./
XAV
An application validator for OCAP, ETV-EBIF, MHP, ACAP and JSR-242 application
conformance testing.
Y
yacc
Yet Another Compiler Compiler. Yacc is a standard parser generator on many
Unix systems. It generates a parser (the part of a compiler that tries to make
syntactic sense of the source code) based on an analytic grammar written in
a notation similar to BNF. Yacc generates the code for the parser in the C
programming language.
Z
Zapper Box
Slang expression for very simple and cheap set-top-boxes that contain minimum
functionality.
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