Note: Descriptions are shown in the official language in which they were submitted.
CA 02324748 2000-11-27
A PROCESS AND A DEVICE FOR DRIVING TERMINALS UNIFORMLY
This invention concerns a process and a device for driving terminals
uniformly, especially
optical and/or acoustic information systems that can be used preferably in the
area of railroad
station systems, including monitors, cameras, loud-speakers, folding
indicators, sensor and/or
updating devices and the like.
In some infrastructures, it is now normal for a large number of sensor and/or
update elements
to be assigned to a large number of function-oriented devices, including
lighting systems, air-
conditioning and ventilation systems, shading units, heating systems,
communications
systems, including su:veillance cameras, monitors, emergency call systems and
loud-
speakers, water and pumping systems and the like. It is also common for not
only the
respective devices themselves, but also the sensor and/or update elements to
be procured at
different times, belong to different generations and have different interfaces
and response
methods.
One special application of this invention is in the field of railroad station
systems, where
different optical andlor acoustic information systems are used for passenger
information, and
terminals like monitors, loud-speakers, folding indicators, video boards and
the like, are
supplied with the corresponding information and controlled by the control
systems provided.
The Deutsche Bahn [German Railroads], for example, is still currently using
passenger
information systems from a wide variety of manufacturers in its train
stations, so that almost
every station is unique in terms of the passenger information system used. The
same is true
of the control devices that exist in the train stations to control the
passenger information
systems and their terminals, which include different computer systems and
networks, and are
basically adapted to the local circumstances of a station. Because of these
conditions,
exchanging data and supplying data for passenger and travel information
between individual
train stations is usually inconsistent. Data of interest for passenger
information include, for
CA 02324748 2000-11-27
example, schedule data in terms of actual and projected data that inform
passengers when the
trains are running, and about delays, connections and the like, for example.
Standardization and integration efforts to control information systems
terminals used in train
stations have thus far failed, since the interfaces between the control
devices and the
terminals of the information systems connected to them in the train station
systems are only
accessible proprietarily, and it is not possible to change information systems
for cost reasons.
Thus, it can happen that older terminals that are still in train station
systems must be
connected to newer control devices. The problem here is that generally the
documentation for
these terminals is no longer around because of their age, and therefore the
drive to integrate
these terminals is difficult and sometimes completely impossible.
In view of this state of the art, the problem of this invention is based on
providing a process
for driving terminals of the type mentioned at the beginning which makes it
possible for
different types of terminals from different types of manufacturers to be
exchanged in almost
any way with one another and makes them able to be driven uniformly,
especially so that it is
possible to exchange changing data and information between various information
systems and
terminals in a way that is consistent and simple.
The invention solves this problem with a process for uniformly driving
terminals, especially
optical and/or acoustic information systems that can be used preferably in the
field of train
station systems, including monitors, cameras, loud-speakers, folding
indicators, sensor and/or
update elements and the like, wherein on the part of at least one control
device, terminals are
grouped in terminal classes in terms of their logic functionality by means of
a standardized
terminal adapter, are connected to a terminal controller over a standardized
terminal interface
and are physically driven by the terminal controller.
According to the invention, the terminals to be driven are driven by at least
one control
device, and the terminals are advantageously grouped into terminal logic
classes, for example
in terminals for outputting a train line, whether it is acoustic or optical,
or in terminals for
processing continual streams of data, for example surveillance cameras and
monitors for
2
CA 02324748 2000-11-27
video data. With the control device, the terminals are driven according to the
basic logic
functionalities in the respective terminal class, i.e., without knowledge of
the exact physical
properties of the individual terminals. The basic logic functionalities and
properties given on
the part of the control device are fed to the terminal controller over the
standardized terminal
interface in the invention, and it finally drives the exact physical
properties of the terminals
selectively. That way, terminals from a wide variety of types and
manufacturers can be
driven uniformly, and can be changed almost any way with one another, which
makes very
consistent data and information exchange possible between different
information systems and
terminals. The procESS in the invention also creates a new standard, which can
be used
advantageously for future new developments in the field of terminals as well,
so that new
developments can be adapted with no problem by existing information systems.
Advantageously, the standardized terminal adapter is connected bidirectionally
to the terminal
controller over the standardized terminal interface, in one preferred
embodiment
unidirectionally. This makes it possible for the control device to respond to
several terminals
via the respective terminal controller, for example to give a track message
over several loud-
speakers or loud-speaker systems that are spread out. Both a natural message
and a synthetic
message that is combined from different partial stored messages can be given
over the loud-
speaker.
In another advantageous embodiment of the invention, a protocol suitable for
text, audio
and/or video data transfer is used for communication between the standardized
terminal
adapter and the control device, for example a multimedia communications
protocol like
H.323 using TCP/IP (Transmission Control Protocol/Internet Protocol).
Advantageously,
text, audio and/or video data are transferred between the control device and
the terminal
controller over the standardized terminal interface. In another advantageous
embodiment of
the invention, the data are transferred coded, and the coding is preferably
done in G.7xx
format for digital coded acoustic signals and in H.26x format for coded image
information.
Different qualities of coded signals, in terms of bandwidth, resolution and
the like, are kept
variable.
CA 02324748 2000-11-27
The H.323 format is a recommendation of the International Telecommunications
Union (ITU)
and sets the standards for multimedia communication over local networks (LAN),
enterprise
networks (Enterprise Net works/EN), urban networks (Metropolitan Area
Networks, MAN)
and wide area networks (Wide Area Networks, WAN). Multimedia communication for
the
Internet can also be used on the basis of the H.323 format. The standardized
H.323 format
supplies a platform for text, audio and/or video data transfer over so-called
packet networks,
like IP (Internet Protocol) for example or IPX (Internet Packet Exchange).
Terminals and
technical software applications in the multimedia field from a wide variety of
manufacturers
can be addressed with this standard and integrated with one another. The use
of the H.323
format allows communication without having to worry about compatibility of the
different
terminals or applications. The H.323 format is thus extremely flexible in
terms of the
possibilities of combining different types of communication. Besides pure
telephony via IP,
called voice-over IP, image telephony, simultaneous audio and data
communication and
simultaneous audio, video and data communication are used. The H.323 format is
designed
to be modular. Thus, many communications protocols already prefabricated and
proven in
practice are used. For the real-time capability needed by audio and/or video
applications, the
H.323 format has modules that use the real-time protocol (RTP) and the real-
time-control
protocol (RTCP). To make and break connections, for example, the Q.932
protocol used for
ISDN services is available in H.323 format, for data communication, modules in
the T.120
protocol family, for example.
In another advantageous embodiment of the invention, to view optic information
on terminals
like monitors or folding indicators, basic functions, like delete at least
part of a message, turn
on, change or add information or partial information, set and/or query current
information or
partial information, query terminal status and query error diagnosis are used.
Moreover, it is
an advantage of the crntrol device that status changes can be detected and
removed, and
maintenance measures can be introduced or carned out. These functions are
called up by the
control device in the invention. Communication between the control device and
the terminal
controller takes place via messages on the logic plane that need no knowledge
of the physical
properties of the respective terminal. Messages can be sent on the part of the
terminal
controller to the control device independently. The messages or data to be
exchanged can be
4
CA 02324748 2000-11-27
converted into the form of telegrams in terminal-specific control commands
(basic
commands) for the terminal controller via the standardized terminal adapter.
The process in
the invention thus not only simplifies the drive, but also standardizes the
operating capacity of
different terminals through the logic drive of terminals on the part of a
control device. Thus,
for example, error messages triggered by the terminal can carry the same logic
name, but have
different meanings depending on the respective terminal. Thus, for example,
error message
"XYZ" from terminal A can mean "paper out," while the same error message from
terminal B
means "cash cassette full." The process in the invention decodes the messages
in the terminal
into uniform logic error messages on the part of the control device.
To display acoustic information on terminals like systems for outputting fixed
texts, loud-
speaker systems with audio coupling or loud-speakers, the respective loud-
speaker circuits are
advantageously driven by the terminal controller to trigger the text to be
voiced. In systems
with audio coupling, the texts to be voiced are advantageously dynamically
transmitted over
an existing network in the area of the information system or forwarded by it.
The loud-
1 S speaker circuit is driven by the respective terminal controller. The audio
signals to be output
are advantageously fed into the respective terminal via the terminal
controller by an audio
interface existing on the standardized terminal adapter. If there is more than
one service for
viewing acoustic information on the terminal, a common terminal controller is
advantageously driven logically to control these services by two standardized
terminal
adapters separated from one another.
The problem is solved by the invention with a generic device to drive
terminals uniformly,
which consists of a terminal controller for physical control of different
terminals and a
standardized terminal adapter for logic control of the terminal on the part of
at least one
control device, wherein the terminal controller and the standardized terminal
adapter are
connected to one another via a standardized terminal interface.
In another advantageous embodiment of the invention, the terminal controller
and the
standardized terminal adapter are designed as modules separated spatially from
one another,
so that the terminal controller can be connected on the part of a terminal and
the standardized
CA 02324748 2000-11-27
terminal adapter can be connected on the part of a control device. Spatial
separation of the
terminal controller and the standardized terminal adapter makes it possible to
use the
infrastructure existing on site in terms of already existing wiring, and makes
it possible to use
the device in the invention, especially on terminals and control devices that
have limited
space available for more module components,. The device in the invention has
the advantage
of untangling the driving complexity. The existing infrastructure, generally
in the form of
bell wires, would not allow a driving process, especially since the
transmission bandwidth of
bell lines is extremely limited. With the process in the invention, to drive
terminals
uniformly over existing bell lines, if necessary, only the physical control
signals for the
terminals need to be transmitted, so that the transmission bandwidth of the
bell lines available
is sufficient. Advantageously, both the terminal controller and the
standardized terminal
adapter have a standardized terminal interface.
In another advantageous embodiment of the invention, the standardized terminal
interface is
designed as an interprocess interface, preferably a Berkley Socket.
Advantageously, the
standardized terminal interface has interfaces for connection to a
communications network,
preferably an Application Programming Interface (API), a LONWorks, an RS232,
an RS485,
a V.24 or the like, for example, an interface for connection to a radio LAN.
Due to the
possibility of connecting to these bus systems, it is also possible to use
wiring that already
exists in the field of train station systems for installed terminals of
information systems.
Preferred transmission media are Ethernet-capable and hence, for example
TCP/IP-capable
transmission media like twisted pairs, preferably category 5/6, or coaxial
lines, radio LANs
and the like. Advant;:geously, the connection between the standardized
terminal adapter and
a control device, for example a computer working as a server, is a connection
based on the
H.323 format, over which the standardized terminal adapter receives
information received by
the control device for passenger information, for example, train delays, track
messages,
changes in arrivals and departures, connection possibilities and the like, and
converts it into
corresponding logic drives for the terminals, for example into acoustic voice
signals coded
with G.7xx or video signals coded with H.26x like moving images and the like.
Other details, features and advantages of the invention will be explained in
greater detail
CA 02324748 2000-11-27
below using examples of embodiment shown in the Figures.
Fig. 1 shows the basic design of the device in the invention;
Fig. 2 shows the basic function of the device in the invention;
Fig. 3a shows the basic design of a first form of embodiment of the device in
the invention;
S Fig. 3b shows the basic design of another form of embodiment of the device
in the invention;
Fig. 3c shows the basic sequence of communication for the device in Fig. 3a;
Fig. 3d shows the basic sequence of communication for the device in Fig. 3b;
Fig. 4 shows a block diagram of the basic functionality of the device in the
invention;
Fig. 5 shows a block diagram of the functionality of the device in the
invention in detail;
Fig. 6 shows a block diagram of how the standardized terminal adapter of the
device in the
invention works
Fig. 7a shows a block diagram of how the terminal controller of the device in
the invention
works using a folding indicator and
Fig. 7b shows a block diagram of how the terminal controller of the device in
the invention
works using a monitor.
Fig. 1 shows the basic design of a device 1 for uniformly driving terminals 2
that are used in
the field of train station systems for optical and/or acoustical passenger
information. Device
1 consists of a terminal controller TC for physical control of different
terminals 2 and a
standardized terminal adapter STA for logic control of terminal 2 on the part
of different
control devices 3, where the terminal controller TC and the standardized
terminal adapter
STA are connected to one another over a standardized terminal interface STI by
means of a
bidirectional communication link 4.
Device 1 separates the logic processing of the information supplied by control
device 3 from
the terminal-specific technology. The standardized terminal adapter STA
describes the
terminal in terms of a logic drive in such a way that functionally equal
terminals are grouped
into terminal families, for example acoustic terminals 2 and optical terminals
2 of information
systems in the form of loud-speakers and video monitors or folding indicators,
as shown in
CA 02324748 2000-11-27
Fig. 2. Physical control of the terminal 2 is exclusively by the terminal
controller TC. The
standardized terminal adapter STA and the terminal controller TC are connected
bidirectionally to one another over the standardized terminal interface STI,
which is designed
as API or another physical transmission medium, like V.24, LONWorks, RS485 or
RS232.
The standardized terminal interface and its communication link 4 guarantee a
uniform basis
for driving all terminals 2 and hence their interchangeability.
Fig. 2 shows how terminals 2 of information systems used in train station
systems can be
driven by means of device 1 on the part of a control device 3 in a uniform,
standardized way.
Device 1 creates a separation between a logic and standardized drive by
control device 3, here
in the form of a so-called station server 3', and a physical terminal drive.
Fig. 3a shows a form of embodiment of device 1, in which the terminal
controller TC and the
standardized terminal adapter STA are designed as a uniform integrated module.
Fig. 3
shows a form of embodiment of device 1 in which the terminal controller TC and
the
standardized terminal adapter STA are designed as modules spatially separated
from one
another.
With the device shown in Fig. 3a, communication takes place between the
terminal controller
TC and the standardiJed terminal adapter STA internally over the standardized
terminal
interface STI.
In the device shown in Fig. 3b, both the terminal controller TC and the
standardized terminal
adapter STA have a standardized terminal interface STI, and the connection
between the
terminal controller TC and the standardized terminal adapter is made over a
communications
network, generally of the existing infrastructure, i.e. bell lines.
Fig. 3c shows the basic communication sequence of one form of embodiment of
device 1 in
Fig. 3a, in which the terminal controller TC and the standardized terminal
adapter STA are
designed as a uniform integrated module. An application 19 running on the
station server 3,
3' to drive a terminal 2 accesses a bidirectional communications link 20 over
an interprocess
CA 02324748 2000-11-27
interface 21, here a Berkley Socket, which obtains access to the bus system of
the server 3, 3'
here an ISA bus 23, via the driver marked 22. On the terminal side, the
terminal controller
TC accesses the bus system 24 via a driver 24; via processing logic 25, the
information to be
exchanged on the part of the application 13 with the terminal 2 for driving is
fed to the
existing input/outputs 26 by the terminal controller TC, which is in turn
controlled by the
processing logic 25 on the part of the terminal controller TC. The
inputs/outputs 26 of the
terminal controller TC are designed here as digital inputs/outputs.
Fig. 3 shows the basic function sequence of device 1 in Fig. 3d, in which the
terminal
controller TC and the standardized terminal adapter STA are designed as
modules separated
spatially from one another.
According to Fig. 3c, an application 19 running on the station server 3, 3' is
fed on the part of
the station server 3,3' over the server's internal bidirectional
communications link 20 to the
interprocess interface 21 designed as a Berkley Socket, which accesses the bus
system 23 via
driver 22. The processing logic 27 can access the bus system 23 via driver 24
of the terminal
controller TC and thus exchange data with the application running on the
station server 3,3'.
In Fig. 3d, the processing logic 27 of the terminal controller TC goes over an
interface, not
shown here, with driver 29 to a bus system 30, which accesses the inputs and
outputs 26
driving the terminal 2 via a corresponding driver 31 of processing logic 28.
The bus system
30, here a LON bus, thus makes it possible to use an already existing
infrastructure, generally
in the form of bell wires, over interfaces responding to the LON driver 29, 31
on the part of
the processing logic 27 and 28.
Figure 4 shows a block diagram with the basic functionality of the drive
device 1, consisting
of a terminal controller TC and the logic drive 6 on the part of the
standardized terminal
adapter STA, between which the standardized terminal interface STI is defined.
Physically,
the standardized terminal interface STI is designed as an interprocess
interface (Berkley
Socket). Under the interprocess interface, an adaptation device, not shown
here, is placed,
which for a distributed drive device 1, corresponding to Fig. 3b in which the
terminal
controller TC is separated from the standardized terminal adapter STA, drives
a
CA 02324748 2000-11-27
communication network 5, here a LON bus or an RS485, which permits the use of
wiring that
already exists to terminals already installed.
The standardized terminal adapter STA gives the different terminals uniform
behavior and
layout. To do so, the standardized terminal adapter has interfaces in its
processing logic 6 to
the station server 3', which supplies the technical information, here train
lines with current
information on incoming and outgoing trains. The standardized terminal adapter
also has a
module 7 (call control) to create a connection design, preferably in H.245
format. This
creates a connection between module 7 (call control) and a gatekeeper 8, which
determines
how a connection is made on the part of the processing logic 6 and controls
how the medium
available for such connection will be used, for example by establishing access
priorities. The
gatekeeper 8 thus determines the quality of the connection, for example in
terms of
transmission bandwidths of acoustic signals to be transmitted or the
resolution of graphics or
moving pictures to be transmitted. Thus, for example, within the framework of
a video
camera used for surveillance, first standard individual low-resolution images
are transmitted
at predetermined intervals of time and, if necessary, when damage occurs, high-
resolution
moving pictures are transmitted continually. The gatekeeper 8 thus controls,
like a digital TK
system used in the field of telecommunications, or permits the display of high-
resolution
graphics with moving picture transmissions or a digitally coded voice signal
via
corresponding terminals 2. It goes back to the dynamic bandwidth management of
the H.323
format. Bandwidth management in H.323 format on corresponding terminals also
makes it
possible to transmit by voice in different qualities and to control cameras.
Cameras can be
switched by control module 7 (call control) via the gatekeeper 6 to individual
image
transmission to obtain rough image information from the camera and to real-
time image
transmission to get more precise, selective image information.
The standardized terminal adapter STA also has a memory module 10, which
handles the
corresponding addressing of the terminals along with a so-called directory
server 9, here an
X500 or LDAP. The directory server 9 also has an image table, which determines
how
individual elements to be displayed, here the elements of a train line, should
be processed and
converted. For a train display with high-resolution graphics, logos of
transporters are filed as
CA 02324748 2000-11-27
bitmaps in the image table of the directory server 9. In addition to the
position of the logo of
a transporter on the train display, the technical layout of the display for
the respective
terminal can be changed uniformly for all terminals using the memory module 10
(cache).
As shown in Fig. 4, the connections between the standardized terminal adapter
are made via
TCP or UDP. The connection 11 between the terminal controller TC and terminal
2 is
terminal-specific and determined on the part of terminal 2. As can be seen
from Fig. 4, the
standardized terming: adapter, the terminal controller TC and terminal 2 form
a so-called
H.323 end point which is clearly established and defined in H.323 format.
Fig. 5 shows how existing information, here train lines 1 to n, is prepared by
the processing
logic 12 on the part of the station server 3' in H.323 format and is forwarded
to the
standardized terminal adapter STA over corresponding interfaces for display,
announcement,
video surveillance, telephony and the like, as a prepared data set. The
station server 3'
receives train lines over a communication network based on the H.323 format,
which has
specific additions for train station systems, for example the ITB format
developed by the
Deutsche Bahn [German Railroads], which is based on H.323 and has applications-
specific
supplements. The train lines are like the counterpart to the schedule boards,
i.e., a data set
with fields for train number, type, platform, arnval and departure time and
the like. From
these train lines, the station server 3' generates corresponding drive
instructions for different
terminal families, for example for optical or acoustic terminals 2. And it
differentiates
between displays wit': one line and those with multiple lines. On a one-line
display, conflict
management must make sure that a punctual train overwrites the display of a
very late train
and then reproduces the display. It must also make sure by corresponding
announcements
that passengers who are waiting for the late train do not inadvertently get on
the train that
meanwhile left on time.
The standardized terminal adapter prepares the data set obtained from the
station server 3'
according to the different terminal classes, like optical or acoustic
terminals. A technical
layout is prepared according to the information obtained from the station
server 3' using a
database from the memory module 10 and the directory server 9. The
standardized terminal
11
CA 02324748 2000-11-27
adapter thus creates a virtual image 13 of the terminal 2, which is forwarded
to the terminal
controller TC over the standardized terminal interface STI. The terminal
controller TC
accepts the technical layout as a virtual image in the form of a data set at
the standardized
terminal interface STI and prepares it specifically for the existing terminal
2, as is explained
below using Fig. 7a and 7b for optical information systems.
Terminal 2 is divided hierarchically, from a logic standpoint, into a display
with one or more
pages with one or more regions, each with different properties. A terminal 2
is described by
the fact that it can contain one or more pages. These pages can be described
independently of
one another. Over the standardized terminal interface STI, any page can become
a page
currently shown on the display. Each page can contain one or more regions.
Depending on
the physical possibilities, the region can be defined in its dimensions
beforehand over the
standardized terminal interface. Each region has different properties. Thus,
for example, on
a palette display, a region is defined by a palette with different folding
pages. Therefore the
region can contain only codes that are assigned to a folding page on the
physical terminal 2.
On a high-resolution graphics display, a region can have the following
properties, for
example: codes, character chain, bitmap and video or movie. Codes are replaced
in the
terminal controller TC by contents reserved there, character chains with
format instructions
such as font, font size, font color and font attributes, which are converted
into corresponding
graphics by the terminal controller TC. Bitmaps can be taken directly by the
terminal
controller TC and displayed on the corresponding region of the terminal 2. If
the terminal 2
supports the display of moving graphics, these can also be displayed directly.
For this, the
terminal 2 has video or movie-type regions. For the video type, the terminal
controller
obtains a continual stream of data over the standardized terminal interface,
which codes
moving pictures according to the H.323 format, for example in H.26x. The movie
type is a
subfunction of the video type, where the data stream here from the terminal
controller 2 is
already in the form o~ a file. That way, the data stream is reduced on the
standardized
terminal interface STI, since the moving pictures must only be transmitted
once, which does
not have to take place under real-time conditions.
Fig. 6 shows the processing logic 6 of the standardized terminal adapter,
which has the job of
12
CA 02324748 2000-11-27
extracting the information in the data set from a logic data set provided by
the respective
station server 3', here in the form of a train line, according to the
respective terminal class. It
is prepared on the basis of the technical layout and transferred into the
regions of the terminal
2 provided for it. For this, the individual fields of the data set are
converted with an
interpreter. The field content is prepared by a sequence of standard commands
for each field
element in the data sets and is transferred into the logic or virtual image 13
of the terminal 2.
The database used for this is created on the basis of the directory server 9,
an X.500 server or
an LDAP server. The directory server 9 allows central data to be held for all
terminals 2. To
prevent unnecessary communication between the directory server 9 and the
terminals 9, the
commands are stored in the interim in the memory module 10, the cache of the
standardized
terminal adapter STA.
Figs. 7a and 7b show the basic functionality of the terminal controller TC for
driving the
terminals 2. Depending on the physical possibilities of the terminal 2, the
information from
the virtual image 13 of terminal 2 is given to the terminal controller TC over
the standardized
terminal interface STI. For the folding indicator shown in Fig. 7, the
processing logic 6 of the
standardized terminal adapter STA has a table with print on individual folding
pages.
Depending on the contents of the region, the corresponding folding-page number
is found and
transmitted to the terminal controller as a code number for the region. The
data is stored, as
already explained, by the directory server 9 and the memory module 10 (cache).
With
terminal 2, shown in Fig. 7b, a monitor that can display high-resolution
graphics, either a
bitmap or pure text is produced as a character chain, which is transmitted to
the terminal
controller TC over the standardized terminal interface STI by the standardized
terminal
adapter STA from the contents of the field for the virtual image 13. For
certain field
contents/regions, there can be databases and a bitmap provided for the
individual values in
the directory server 9 and memory module 10, for example logos for
transporters.
The terminal controller TC receives the data for the different, physically
similar classes of
terminals. These data are prepared and displayed by the terminal controller
for the respective
specific terminal. For the folding indicator shown in Fig. 7a, this means that
the code
numbers for individual regions are converted into set commands for step motors
in the
13
CA 02324748 2000-11-27
folding palette. This corresponds to the code number of a folding position
within the palette.
On the monitor in Fig. 7b which can show high-resolution graphics, for each
region, code
numbers, character chains or bitmaps are given for contents filed permanently
in the terminal
controller TC,. A continual stream of data can also be supplied by the station
server 3' over
the standardized terminal interface STA, which can be interpreted by the
terminal controller
S TC as video data, using H.26x coding. That way, there is fading of moving
advertisements
on a train display or another monitor.
On acoustic terminals 2, not shown here, the continual stream of data has
acoustic
information coded by G.7XX as part of the H.323 format. The regions are
interpreted as
elements of a synthetic announcement by the terminal controller, so that any
announcement
can be composed from pre-stored speech elements.
14
CA 02324748 2000-11-27
List of Reference Numbers
1 Drive device TC terminal controller
2 Terminal STA standardized terminal adapter
3 Control device STI standardized terminal interface
3' Station server
4 Communications link
5 Communications network
6 STA processing logic
7 STA call control
8 Gatekeeper
9 Directory server
10 Memory module (cache)
11 Communications link
12 Processing logic
13 Virtual image
14 Controls
15 Controls
16 Communications link
17 Communications link
18 Communications link
19 Application
20 Communications link
21 Interface
22 Driver
23 Bus system
24 Driver
25 TC processinb logic
26 Inputs/outputs
27 Processing logic
28 Processing logic
29 Driver
30 Bus system
31 Driver
16
