U.S. patent application number 10/368472 was filed with the patent office on 2003-08-07 for pbx with short messaging service on a telephone display.
This patent application is currently assigned to Tadiran Telecom Business Systems Ltd.. Invention is credited to Neuman, Aharon.
Application Number | 20030147382 10/368472 |
Document ID | / |
Family ID | 22933865 |
Filed Date | 2003-08-07 |
United States Patent
Application |
20030147382 |
Kind Code |
A1 |
Neuman, Aharon |
August 7, 2003 |
PBX with short messaging service on a telephone display
Abstract
Method and apparatus for sending and displaying short messages
from data network users which are linked to a telephonic network.
The telephonic network comprises telephones, each with a display
for visually displaying short messages to subscribers of the
telephonic network. The apparatus holds a dialogue between the data
network users and a software agent embedded in the telephonic
network. The dialogue provides the telephonic network the content,
the sender ID and the address information of each short message,
stores the content and address information in a database, and
displays the content of the messages on the telephone display of
each destined subscriber.
Inventors: |
Neuman, Aharon; (Ramat Gan,
IL) |
Correspondence
Address: |
Harold L. Novick
NATH & ASSOCIATES PLLC
1030 15th Street, N.W. - 6th Floor
Washington
DC
20005
US
|
Assignee: |
Tadiran Telecom Business Systems
Ltd.
|
Family ID: |
22933865 |
Appl. No.: |
10/368472 |
Filed: |
February 20, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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10368472 |
Feb 20, 2003 |
|
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|
09247170 |
Feb 9, 1999 |
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Current U.S.
Class: |
370/352 |
Current CPC
Class: |
H04M 1/2535 20130101;
H04L 51/04 20130101; H04M 1/57 20130101; H04L 51/066 20130101; H04M
7/12 20130101; H04M 3/42314 20130101 |
Class at
Publication: |
370/352 |
International
Class: |
H04L 012/66 |
Claims
1. A method for sending and displaying short messages from at least
one data network user to at least one subscriber of a telephonic
network, said telephonic network having at least one telephone,
said at least one telephone having a display for visually
displaying said short messages.
2. A method according to claim 1, further comprising holding a
dialogue between the data network users and a software agent
embedded in the telephonic network, said dialogue providing said
telephonic network the content and the address information of each
short message, storing said content and address information in a
database, and displaying the content of said messages on the
telephone display of each destined subscriber.
3. A method according to claim 1, wherein the short message is sent
as a single message, said message containing the content and the
address information of each short message.
4. A method according to claim 1, wherein at least one telephone
from said plurality of telephones having a display and an
indicating circuitry for providing indications about arriving
messages.
5. A method according to claim 1, wherein said telephonic network
is a PBX.
6. A method according to claim 1, wherein the telephonic network is
connected to said data network via a LAN, said LAN connecting a
plurality of local users and being capable of exchanging
addressable data between each data network user and each local
user.
7. A method according to claim 1, wherein said at least one
telephone of said telephonic network having a display, an
indicating circuitry for providing indications about arriving
messages, and means for retrieving messages from said database.
8. A method according to claim 2, wherein the storage of short
messages comprises: a) generating a first data structure, in which
all messages destined to the same extension are linked; b)
generating a second data structure, in which each message is
separately stored according to its destined extension; c) storing
each arriving short message in said second data structure; d)
organizing said stored short messages with links between messages
destined to the same extension; and e) storing said linked messages
and the remaining unlinked messages in said first data
structure.
9. A method according to claim 1, wherein the data network is a
packet switched network.
10. A method according to claim 1, wherein the data network is the
Internet or an Intranet.
11. Apparatus for receiving and displaying short messages from at
least one data network user to at least one telephone of a
telephonic network, said at least one telephone having a display
for visually displaying said short messages, in which, said at
least one telephone is connected to a PBX, which comprises:
circuitry and software for receiving a message from said data
network users, and circuitry for displaying the content of said
messages on the telephone display of each destined subscriber.
12. Apparatus according to claim 11, further comprising a call
manager embedded in the telephonic network, circuitry for providing
said call manager the content, the sender ID and the address
information of each short message, a database, and circuitry for
storing said content and address information in said database.
13. Apparatus according to claim 11, further comprising telephones
with no display.
14. Apparatus according to claim 11, comprising circuitry for
storing messages for retrieval, and circuitry for providing
retrieval.
15. Apparatus according to claim 11, wherein at least one telephone
from said plurality of telephones having a display and an
indicating circuitry for providing indications about arriving
messages.
16. Apparatus according to claim 11, wherein said telephonic
network is directly connected to said data network.
17. Apparatus according to claim 11, wherein said telephonic
network is connected to said data network via a IAN, said LAN
connecting a plurality of local users and being capable of
exchanging addressable data between each data network user and each
local user.
18. Apparatus according to claim 11, wherein the data network is a
packet switched network.
19. Apparatus according to claim 11, wherein said data network is
an IP network.
20. Apparatus according to claim 11, wherein the circuitry
comprises a plurality of peripheral interface cards being connected
to telephonic subscribers and/or to a LAN for establishing
communication paths between said telephonic subscribers and a
plurality of data network users via said LAN.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to the field of
communications. More particularly, the invention relates to an
apparatus for sending short messages over a telephonic network from
Internet Protocol (IP) users linked to the telephonic network, to
subscribers of the network, and directly displaying the message on
the display of their telephone terminals.
BACKGROUND OF THE INVENTION
[0002] The use of Short Message Services (SMS) is widespread and
rapidly penetrating the market of cellular telephones. Short
messages are also delivered from a base station to a plurality of
subscribers by pagers, using radio communication channels.
Additional applications, such as news, weather and traffic
information also employ short messages that are delivered to
rapidly update subscribers.
[0003] Another type of subscribers are subscribers that are
connected to an information system via a telephonic connection. For
example, subscribers such as employees in an organization normally
are connected to a Private Branch Exchange (PBX) via personal
telephone terminals. These telephone terminals, sometimes known as
"smart telephones", comprise a small display, usually for
displaying the time, date, name/identification of another PBX
caller (subscriber) from the same organization and call duration
measurement. These smart phones usually have a voice message
recording capability in their inherent circuitry or in a
corresponding memory cell located in the PBX. However, these voice
messages are not promptly accessible and therefore, not effective
when on line update is required. In addition, in order to access a
PBX subscriber, it is necessary to dial up through the Public
Switched Telephone Network (PSTN) and have access to the extension
of the subscriber via the PBX.
[0004] Local Area Networks (LANs) enable several computers (users)
to be connected to a computer network which is normally limited to
the immediate area and operates according to one of the common
networking protocols, such as Ethernet. PBXs sometimes comprise a
built in path for connection to a LAN, that may also be connected
to an IP network such as the Internet or Intranet via a router.
Therefore, a physical connection is established between IP users
that are distributed over the IP network and subscribers of the
PBX. Messages may also be sent to a subscriber via E-mail, but this
implies that the subscriber is connected to the LAN via a computer
and that the E-mail application is continuously active. It is
therefore desirable to provide a communication path between IP
users and each extension of the PBX, that enables each subscriber
equipped with a smart telephone to receive short messages from an
IP user directly and promptly on his telephone display.
[0005] Several Voice Over IP (VOIP) techniques are employed to
communicate IP users with subscribers of a PBX. Some of them employ
gateway architectures (manufactured by, among others, Vocaltec and
Netspeak) for this connection, which enable IP users to establish a
voice call over the IP network. Although these architectures
provide a communication path between the IP network and the PBX,
they are limited to VOIP and can not be used to access the
subscriber telephone display.
[0006] While E-mail is well known in the industry, it requires the
recipient to have a computer, and to be connected to the E-mail
delivery network, or to connect to the network in order to receive
his E-mail. In adition, E-mail is not a real-time delivery network,
typically involving a server computer in between the sender and the
recipient.
[0007] U.S. Pat. No. 5,381,461 describes a telephone terminal with
interactive display arrangement, which sufficiently provides a
desired level of clarity to a user who wishes to move about in a
hierarchy of menu screens available on the display. However, this
arrangement is associated only with the visual interaction between
the user and messages that represent operating features of the
telephone terminal. No message delivery features from one telephone
terminal to another are available, and the messaging functionality
is limited to each specific terminal.
[0008] U.S. Pat. No. 5,392,337 describes an arrangement for varying
the display time for messages displayable on a telephone terminal,
according to the length and the complexity content of the
information in each message. Here again, the messaging
functionality is limited to each specific terminal.
[0009] U.S. Pat. No. 5,768,509 describes a Short Message Server
(SMS) with relatively limited memory requirements, for storing
messages destined to subscribers via a mobile telephone system. The
SMS does not keep a subscriber database, but rather utilizes
information stored in a Home Location Register (HLR) database to
determine whether a message destination is valid and/or authorized.
However, this SMS is designed to serve mainly TCP/IP based network,
not subscribers of a Private Branch Exchange (PBX).
[0010] All the methods described above have not yet provided
satisfactory solutions to the problem of sending a short message
from IP users to a telephonic subscriber which may be directly
displayed on his telephone display.
[0011] It is an object of the present invention to provide a method
and apparatus for displaying a short message sent from an IP user
to a telephonic subscriber, which overcome the drawbacks of prior
art.
[0012] It is another object of the present invention to provide a
method and apparatus for displaying a short message sent from an IP
user to a telephonic subscriber directly on his telephone
display.
[0013] It is still another object of the present invention to
provide a method and apparatus for displaying a short message sent
from an IP user to the telephone display of a telephonic subscriber
using unsophisticated software.
[0014] Other objects and advantages of the invention will become
apparent as the description proceeds.
SUMMARY OF THE INVENTION
[0015] The present invention is directed to a method for sending
and displaying short messages from IP users which are linked to a
telephonic network via a LAN and an IP network, such as the
Internet, to subscribers of the telephonic network. By using the
term "IP network" it is meant to include any nework or any system,
in which data packets are arranged and transferred according to the
Internet Protocol (e.g., the Internet, an Intranet, a LAN, a WAN
and others) or any other "packet switched network" including any
nework or any system, in which data is divided to packets of fixed
or variable size and then transferred to its destination.
[0016] A dialogue is held between said IP users and a call manager
embedded in the telephonic network. The dialogue provides the call
manager the content, sender ID and address information of each
short message. The sender ID may include any type of information
that can identify the sender, such as a code, his real name, a
nickname, his E-mail adress etc. The content and sender ID
information are stored in a database, providing each subscriber an
indication about received short messages, and the messages are
displayed on his telephone display in response to a signal from the
subscriber.
[0017] Preferably, a plurality of IP users are distributed over the
IP network with direct access to the IP network. Preferably, a LAN
is used to connect a second plurality of local users, and a router
is used to connect between the LAN and the IP network. A PBX is
linked to the LAN, and is connected to a plurality of extensions.
The PBX is capable of storing and converting incoming IP data from
the IP network to a telephonic protocol and transferring the
converted data to each extension. A plurality of smart telephones
are connected to corresponding extensions of the PBX. Each
telephone comprises a display for visually displaying arriving
messages and an indicating circuitry for providing indications
about arriving messages. The PBX also comprises a processing
storage and control circuitry for processing and storing arriving
messages and sending them to their destined PBX extension according
to address information, and a software agent for chatting with the
IP user by sending to and receiving from the user, data packets in
chat mode. By using the term "chatting", it is meant to describe a
visual/textual, real-time, bi-directional transmission between two
entities connected via an IP network in a bi-directional session.
While chatting, messages are delivered immediately, without the
need to store them first in a server. A connection is established
between the IP user and the software agent by operating an SMS to
PBX or chat software by the IP user and providing the IP address of
the PBX. Each IP user (sender) who wishes to send a short message
operates chat software to communicate with the software agent. Each
short message contains address and a text fields, delimited by
prefixed characters. The software agent, embedded into the LAN
interface card, collects the content and address information of
short messages obtained during each chat session, and sends them to
the call manager software which resides on the main call processor
board, which processes the collected information and stores the
information separately for each destined extension. The LAN
interface card sends a confirmation message to said IP user. An
indication is sent to the subscriber's telephone which is connected
to the destined extension and operates a beep and/or a blinking
lamp in the telephone. Upon receiving a request signal from the
destined subscriber, all stored short messages which are destined
to said extension are retreived from said storage and control
circuitry and sent to the display of said subscriber's telephone
over the telephonic connection between the PBX and the destined
extension.
[0018] The invention is also directed to an apparatus for sending
and displaying short messages from IP users which are linked to a
telephonic network via a LAN and/or an IP network, such as the
Internet, to subscribers of the telephonic network. The apparatus
comprises circuitry for holding a dialogue between said IP users
and a call manager embedded in said telephonic network, circuitry
for providing said call manager the content, sender ID and address
information of each short message, circuitry for storing said
content and address information in a database, circuitry for
providing each subscriber an indication about sent short messages
and circuitry for displaying the content of said messages on his
telephone display in response to a signal from said subscriber.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The above and other characteristics and advantages of the
invention will be better understood through the following
illustrative and non-limitative detailed description of preferred
embodiments thereof, with reference to the appended drawings,
wherein:
[0020] FIG. 1 illustrates the communication path between an IP user
and the telephone display of a destined subscriber, according to a
preferred embodiment of the invention;
[0021] FIG. 2 is a block diagram of the PBX circuitry, employing a
software agent and a call manager, according to a preferred
embodiment of the invention;
[0022] FIG. 3 is a flowchart of the LAN interface card operation,
according to a preferred embodiment of the invention;
[0023] FIG. 4 is a flowchart of the main call manager application
operations, used to interact with peripheral devices in response to
requests from the LAN interface card; and
[0024] FIG. 5 is a flowchart of the program for reading a sent
short message, according to a preferred embodiment of the
invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0025] FIG. 1 illustrates the construction of a communication path
between an IP user and the telephone display of a subscriber that
is connected to an extension of a PBX, according to a preferred
embodiment of the invention. A plurality of IP users 10 are
connected to an IP network 11 which may be, for instance, the
Internet. A LAN 12, which comprises a plurality of users 15 and a
server 13, is connected to the IP network 11 via a router 14, which
is normally a special purpose computer that handles the connection
between the LAN 12 and the IP network. Router 14 routes data
packets to destinations, according to their addresses. A PBX 16,
which is linked to the LAN 12, comprises a plurality of extensions
each of which is terminated with a smart telephone 17 with a visual
display 18. Optionally, additional extentions may be terminated
with standard telephones which may be compatible with Plain Old
Telephone Services (POTS), with no messaging capability.
[0026] In this example, an IP user 10 named `Roni` wishes to send
an urgent short message to a subscriber named "Dror" whose
telephone extension is #2352 of the PBX 16. According to a
preferred embodiment of the invention, the IP user 10 operates a
software in his computer which is able to access the PBX 16 via a
unique address in the IP network. This software connects the IP
user to the PBX 16 via the IP network 11, router 14 and LAN 12. A
software agent in the PBX 16 introduces text questions, or
optionally vocal questions to the IP user about the subscriber (to
whom the short message is destined) details, such as extension
number or name, and provides the IP user text, or optional voice
instructions indicating how to type the short message in his
computer. The short message is sent as packets over the
communication path, and saved in a Main Call Processor (MCP) at the
PBX. The MCP sends the short message to the telephone display over
a standard link within the PBX 16. In this configuration, users 15
connected to the LAN 12 can also send a short message to the
telephone display of any extension.
[0027] The transfer of data packets (e.g., VOIP and/or text
messages) may be carried out in Transmission Control
Protocol/Internet Protocol (TCP/IP) (commonly used in the Internet)
which is associated with the Network and Transport layers. A higher
layer protocol, which may be standard or proprietary, is required
for the SMS path. This higher layer protocol is implemented by a
software program that is operated by each IP user (sender) 10 and
embedded in the PBX 16. According to a preferred embodiment of the
invention, a chat program that enables real time data communication
is employed with no need for a special server. The PBX comprises a
software that can handle incoming chat calls by a software agent (a
"dummy" chat partner) and manage a basic dialogue with the IP user
10, so as to instruct the IP user about required details to be sent
with the message. In the message example of FIG. 1, the IP user is
asked to type first the desired extension number (2352) followed by
a `;` which indicates the end of the destination and then to type
the message followed by `!` which indicated the end of the message.
This program is advantageous since the sender is not required to
operate a special program and no additional specialized software
needs to be downloaded for each PBX, and senders can simply use
their standard chat software, such as ICQ software (by Mirabilis),
as long as the PBX software agent has been programmed with a
compatible chat software.
[0028] The IP user may send a short instant message to the PBX or
chat with the software agent at the PBX. According to a preferred
embodiment of the invention, an IP user 10 may communicate with the
PBX 16 using a long dialogue mode. In this mode, the IP user
operates an SMS to PBX communication program which provides the
address of the destined PBX and then begins chatting with a
software agent (a dummy user) at the PBX.
[0029] The following dialogue represents an example of a long
dialogue mode. In the example a remote user named `Shiri` wishes to
send the short message "I will call you tomorrow morning" to a PBX
subscriber named `Roni`. The PBX is linked to a site named
`Tadiran`.
[0030] Tadiran"You have reached the Tadiran's Coral agent. Send
short message to:"
[0031] Shiri"Roni"
[0032] Tadiran"Type your message (max 80 characters) followed by
`!`"
[0033] Shiri"I will call you tomorrow morning. !"
[0034] Tadiran"Your message has been delivered successfully.
Good-bye"
[0035] According to another preferred embodiment of the invention,
an IP user 10 may communicate with the PBX 16 using a short
dialogue mode. In this mode, the IP user may start the connection
with the destined PBX by operating an SMS to PBX program that
provides the IP address of the destined PBX and may send an instant
message with full details of the destination adress, including the
extention number in the PBX or the recepient's name, in a single
transmission. The message is sent in a specified format, using a
";" as a delimiter between the ID information and the message, and
then his message followed by a `!` or any other predetermined
character. In this case, no chat session is initiated, and a
response (which is also sent as an instant message) is sent only in
the event of a problem, such as a wrong adress. Instant messaging
is a mode of IP messaging, where the message is sent and delivered
promptly, and not stored on an intermediary server.
[0036] The following dialogue represents an example of a short
dialogue mode. In the example a remote user named `Shiri` wishes to
send the short message "I will call you tomorrow morning" to a PBX
subscriber named `Roni`. The PBX is linked to a site whose IP
adress is `Tadiran.pbx`.
[0037] Shiri"Rony; I will call you tomorrow morning."!
[0038] After the short message is sent to the subscriber located at
the destined extension, the message data drives one or more of the
features of the smart telephone at the destined extension. For
example, the smart telephone may announce a short beep and/or the
message LED may start blinking or a message button may be
illuminated. The subscriber may read a sent short message by
pressing predefined keypad buttons or the short message button.
Up/down arrows may be used by a subscriber for browsing his
messages. After deleting all messages, the illumination of the
button is terminated. A prefixed combination of keypad buttons such
as "#0" may be pressed to delete a message.
[0039] FIG. 2 is a block diagram of the PBX circuitry portion, that
controls the display telephones by the call manager, according to a
preferred embodiment of the invention. The circuitry portion 20
comprises a Main Call Processor Board 201, which is used to run a
main call manager application that interacts with peripheral
devices through a peripheral card controller 202 which controls
message delivery through one of the peripheral cards. Peripheral
devices may comprise Plain Old Telephone Services (POTS), smart
telephones, Public Switched Telephone Network (PSTN) lines and
LANs. Each peripheral card functions as a specific driver for one
of the peripheral devices. The group peripheral cards may comprise
a POTS interface card 203, a smart phone interface card 204, a PSTN
interface card 205 and a LAN interface card 206 which is used in
this example to connect the circuitry portion 20 to an Ethernet LAN
207. The LAN interface card 206 contains the software agent which
provides the dialogue with IP users. The main call manager
application is a software program that saves incoming messages to
the PBX's subscribers and is run by the Main Call Processor Board
201, which is also used to run the short message feature that
controls message delivery from the PBX to the destined extension.
It is to be noted that the main call manager applicated herein,
discussed in only part of total main call manager application which
actually controls the functioning of the PBX.
[0040] FIG. 3 is a flowchart of the LAN interface card operation,
according to a preferred embodiment of the invention. At the first
step 301 the LAN interface card carries out initialization
procedures. At the next step 302 the LAN interface card waits for a
short message initialization from an IP user. At the next step 303
the LAN interface card checks if the initialized message is a short
form SMS to PBX message or a long dialog form. If the message is a
long dialog form, a greeting message is sent to the IP user at the
next step 304. At the next step 305 the LAN interface card waits
for ID information about the desired message destination. At the
next step 306 the ID information is sent to the main processor
board 201 for validation using the call manager application
software. On the other hand, if the message is a short dialogue,
steps 304 and 305 above are skipped and the ID information is
directly sent to the main processor board 201 for validation
according to step 306. At the next step 307 the call manager
application software checks if the ID information is valid. If the
ID information is not valid, at step 308 a message indicating that
the ID information is invalid is sent to the IP user. If the ID
information is valid, at the next step 309 the software agent
checks if the message comprises prefixed delimit and termination
characters that define the message limits. If the message limits
complies with the prefixed delimit and termination characters, at
the next step 310 the ID information together with the content of
short message are sent to the Main Call Processor where the call
manager software resides. In the same time a confirmation message
is sent to the IP user (sender). If the message limits do not
comply with the prefixed delimit and termination characters, a
message containing a request for text is sent back to the IP user
at step 311, and the LAN interface card waits for a (new) correct
message text at step 312. As soon as a correct text message is
sent, the ID information together with the content of short message
are sent to the Main Call Processor and in the same time a
confirmation message is sent to the IP user, according to step 310
above.
[0041] According to a preferred embodiment of the invention, short
messages arriving to the Main Call Processor Board 201 are stored
in two data structures. The first data structure, named "Short
Message Text" (SMT) is a kind of a "memory pool", in which short
messages that belong to the same extension (i.e., to the same smart
telephone, also named DKT) are linked. Table 1, which comprises an
Entry field, a Text field, a Sender ID field and a Next Entry
field, is an example of the first data structure:
1 TABLE 1 Entry # Text Sender ID Next Entry # 0 Text #0 2 1 Text #1
Null 2 Text #2 Null 3 4 5
[0042] Incoming messages are organized such that at the end of each
entry, the next entry # field provides information about the next
entry which is also destined to the same extension. If a current
entry is the last one for the same extension, the next entry for
this extension is a null. The first entry (#0) in Table 1 comprises
a short message "Text #0", destined to extension #XXXX. The next
entry for extension #XXXX is entry #2 which contains "Text #2",
with no further entries (indicated by a null for its next entry).
The second entry (#1) in Table 1 comprises a short message "Text
#1", destined to extension #YYYY", with no further entries
(indicated by a null for its next entry).
[0043] The second data structure, named "DKT driver" comprises one
entry for each DKT. Table 2, which comprises an Entry number, an
Extension field, a Name field and a Short Message field, is an
example of the second data structure:
2 TABLE 2 Entry # Extension # Name . . . ShortMsg . . . 0 2825 Roni
0 1 2360 Rachel 1 2 2181 Moses Null 3 . . . . . . Null 4 . . . . .
. Null
[0044] Table 2 is organized such that each entry relates to
corresponding (destined) extension, name and pointer to the first
message in the SMT data structure pertinent to this extention. In
the example of Table 2, the message(s) for extension 2825 are found
starting at entry #0 in the SMT data structure, and the message for
extension 2360 are found starting at entry #1. There are no
messages waiting for extension 2181.
[0045] FIG. 4 is a flowchart of the main call manager application
operations (employed by the Main Call Processor Board 201), which,
according to a preferred embodiment of the invention, is used to
interact with peripheral devices in response to requests from the
LAN interface card 206. At the first step 401, the main call
manager waits for an incoming message from the LAN interface card
206. At the next step 402 the main call manager checks if there is
a request for validation of ID information. If there is a request,
the main call manager checks the ID information and Name fields and
thereafter sends a response to the LAN interface card at step 403.
If there is no such request, at the next step 404 the main call
manager checks if there is a new short message. If there is, at the
next step 405 the main call manager adds the new message to the SMT
data structure (exemplified by Table 1) and updates the DKT driver
data structure (exemplified by Table 2) if necessary (i.e, if there
was no previous messages in the SMT data structure). In addition,
an indication signal (such as a short beep and/or a blinking
message lamp and/or an illuminating short message button) is lit in
the smart telephone connected to the destined extension. Prior to
lighting the lamp, the current status is first checked, as if it
lit, no lighting message needs to be sent. However, an audible
signal may be sent with each new message that is received. If there
is no new message, the next operation is to return to step 401 and
wait.
[0046] FIG. 5 is a flowchart of the program for reading a sent
short message, according to a preferred embodiment of the
invention. The first step 500 is a waiting stage until the
subscriber operates the message button to see his short messages.
At the next step 501, the main call manager reads the second data
structure (the DKT driver) and sets the pointer to the first
message in the first (SMT) data structure. If the reading is a
null, at step 502 a "no messages" text is displayed on the
subscriber's telephone display. If the reading is not a null, at
the next step 502 the message at the pointer is sent and displayed
on the subscriber's telephone display. At the next step 503, the
program waits for inputs from the subscriber. The subscriber may
scroll through the messages by using one of the known methods, such
as arrow keys found on most display phones. This is well known in
the PBX industry.
[0047] If the subscriber pushes the #0 buttons, the read message is
erased from the first (SMT) data structure at the next step 504, by
replacing the contents of the next Entry # field that points to the
erased message, with the content of the next Entry # field of the
message being erased. If the deleted message is the first message
in the first (SMT) data structure, at the next step 505 the second
data structure (the DKT driver) is updated with the new location,
and the program returns to step 501. If there are no messages left,
the message lamp is turned off.
[0048] If the subscriber pushes the down-pointing arrow (in the
displayed menu), at the next step 506 the program checks if the
displayed message is the first message in the SMT data structure.
If it is, the program continues to display the message (step 502),
and returns to step 503 and waits for inputs. If not, at the next
step 507, the pointer is decremented to the previous entry. The
message at the pointer is displayed at step 502, and the program
returns to step 503.
[0049] If the subscriber pushes the up-pointing arrow (in the
displayed menu), at the next step 506 the program checks if the
displayed message is the last message in the SMT data structure. If
it is, the program continues to display the message at step 502,
returns to step 503 and waits for inputs. If not, at the next step
509, the pointer is incremented to the next entry and the program
displays the next entry at step 502, and returns to step 503.
[0050] The above examples and description have of course been
provided only for the purpose of illustrations, and are not
intended to limit the invention in any way. As will be appreciated
by the skilled person, the invention can be carried out in a great
variety of ways, employing more than one technique from those
described above, all without exceeding the scope of the
invention.
* * * * *