Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF THE INVENTION
Apparatus and method to use a conventional telephone
set to make telephone calls on a packet network.
FIELD OF THE INVENTION
The present invention relates to packet networks. More
specifically, the present invention is concerned with a method and an
apparatus to use a conventional telephone set to make telephone calls
on a packet network.
BACKGROUND OF THE INVENTION
The prior art is replete with software enabling a first user
to establish a telephone-like conversation with a second user running the
same software via a packet network, such as, for example, the Internet.
These softwares usually run on personal computers
equipped with microphones to capture the sounds and with sound cards
to reproduce the sounds from the other user. The software therefore
captures the sound from a first user, digitises it, compresses it, and
forwards it to the Packet Network address (Internet Protocol address or
IP address) of the second user. The sounds is then uncompressed,
transferred back to analog sound by the sound card and reproduced on
the premises of the second user. Of course, these steps are performed
bidirectionally to result in a full duplex connection.
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The drawbacks of the above mentioned software system
are multiple. For example, a dedicated PC must be used as a telephone,
both users must be similarly equipped and running the same software
and it is not possible to reach users equipped with conventional
telephones.
OBJECTS OF THE INVENTION
An object of the invention is to provide an apparatus and
a method to use a conventional telephone set to make telephone calls on
a packet network.
SUMMARY OF THE INVENTION
More specifically, in accordance with the present
invention, there is provided a telephone to packet adapter comprising:
a telephone line intertace configured to be connected
to a telephone line;
a telephone interface configured to be connected to a
telephone set;
a Local Area Nefinrork interface configured to be
connected to a packet network;
a controller circuit interconnecting the telephone line
interface, the telephone interface and the Local Area Network interface;
the controller circuit being so configured as to route the telephone
intertace to one of the telephone line and the Local Area Network
interfaces depending on at least one preestablished routing rule
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According to another aspect of the present invention,
there is provided a telephone to packet adapter comprising:
a telephone line interface configured to be connected
to a telephone line;
a telephone interface configured to be connected to a
telephone set;
a Local Area Network interface configured to be
connected to a Local Area Network;
a packet network interface configured to be connected
to a packet network; and
a controller circuit interconnecting the telephone line
interface, the telephone interface, the Local Area Network interface and
the packet network interface; the controller circuit being so configured as
to either a) route the telephone interface to one of the telephone line and
the packet network interfaces and b) route the Local Area Network
interface to one of the telephone line and the packet network interfaces
depending on at least one preestablished routing rule.
According to another aspect of the present invention,
there is provided a method for routing telephone calls to a packet network
via a telephone to packet adapter provided with a telephone line
interface, a telephone interface, a Local Area Network interface and a
controller circuit interconnecting the telephone line, telephone and Local
Area Network interfaces; the method comprising the steps of:
connecting a telephone line to the telephone line
interface;
connecting a telephone set to the telephone interface;
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connecting a packet network to the Local Area Network
interface;
running an agent software for routing the telephone
interface to either the conventional telephone line interface and the Local
Area Network interface depending on at least one preestablished routing
rule.
According to yet another aspect of the present invention,
there is provided a method for routing telephone calls to a packet network
via a telephone to packet adapter provided with a telephone line
interface, a telephone interface, a Local Area Network interface, a packet
network interface and a controller circuit interconnecting the telephone
line, telephone, packet network and Local Area Network interfaces; the
method comprising the steps of:
connecting a telephone line to the telephone line
interface;
connecting a telephone set to the telephone interface;
connecting a Local Area Network to the Local Area
Network interface;
connecting a packet network intertace to the packet
network interface;
running an agent software for routing either a) the
telephone interface to one of the conventional telephone line interface
and the packet network interface, and b) the Local Area Network interface
to one of the conventional telephone line interface and the packet
network interface, depending on at least one preestablished routing rule.
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It is to be noted that the term "telephone call" is to be
construed as meaning any calls conventionally made via telephone lines
such as, for example, voice calls, fax calls and modem calls.
Accordingly, the term "telephone set" is to be construed as meaning any
5 device that produces signals capable of being understood by PSTN
equipment expected signals from a conventional telephone set (also
known as a POTS (Plain Old Telephone System) telephone set).
Therefore, the term "telephone set" includes any POTS devices such as,
for example, fax machines, modems and even more advanced devices
such as H.324 video phones.
Other objects, advantages and features of the present
invention will become more apparent upon reading of the following non
restrictive description of preferred embodiments thereof, given by way of
example only with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the appended drawings:
Figure 1 is a schematised block diagram illustrating the
various components of a telephone to packet adapter according to a first
embodiment of the present invention.
Figure 2 is a schematised block diagram illustrating a
packet network where users are provided with telephone to packet
adapters according to an embodiment of the present invention;
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Figure 3 is a flow diagram illustrating the general steps
taken to establish a communication between user 2 and one of users 1
or 3 of Figure 2;
Figure 4 is a flow diagram illustrating the general steps
taken to establish a communication between user 1 and user 2 of Figure
2;
Figure 5 is a flow diagram illustrating the general steps
taken to establish a communication between one of users 1 or 2 and user
3 of Figure 2; and
Figure 6 is a schematised block diagram illustrating the
various components of a telephone to packet adapter according to a
second embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Figure 1 of the appended drawings illustrates a block
diagram of a full duplex telephone to packet adapter 10 according to a
first embodiment of the present invention.
The adapter 10 includes a telephone input/output (10)
port 12 to which a conventional telephone (not shown) may be
connected, a Local Area Network (LAN) 10 port 13 trough which
connectivity to a LAN or to a Personal Computer (PC) (not shown) is
obtained, a telephone line 10 port 14 to which a telephone line (not
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shown), part of the Public Switched Telephone Network (PSTN), may be
connected and a packet network interface 10 port 16 to which a packet
network (not shown) may optionally be connected.
The adapter 10 electronic circuitry generally includes an
analog to digital (AID) and a digital to analog (DIA) full duplex interface
18 interconnecting a controller circuit 20 and the 10 port 12, a Local Area
Network interface 23 interconnecting the controller circuit 20 and the 10
port 13, a speech encoderldecoder 22 connected to the controller circuit
20, a telephone line intertace 24 interconnecting the controller circuit 20
and the 10 port 14 and a packet network interface 26 interconnecting the
controller circuit 20 and 10 port 16.
The controller circuit 20 is' provided with a central
processing unit (CPU) and sufficient memory to store a software agent
program and other data stored in databases as will be further described
hereinafter.
The speech encoderldecoder 22 includes the required
circuitry to perform digital speech andlor data encoding and decoding to
decrease the bandwidth required to transfer the information from one
user to another and to recuperate the complete information after the
transfer.
It is believed within the 'reach of one skilled in the art to
provide adequate electronic circuitry for the elements 18-26 described
hereinabove.
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Turning now briefly to Figure 6 of the appended
drawings; a telephone to packet adapter 400 according to a second
embodiment of the present invention will be described.
The telephone to packet adapter 400 is very similar to
the telephone to packet adapter 10 described hereinabove. Thus, for
concision purposes, only the differences between these adapters will be
described herein.
As can be seen from Figure 6, the telephone to packet
adapter 400 is designed to be connected to a packet network 30 via a
Local Area Network 31. Thereby, the telephone to packet adapter 400
does not require a packet network interface 26 (Figure 1 ). It is to be
noted that the Local Area Network 31 therefore includes a packet network
LAN gateway as is very well known in the art.
Figure 2 of the appended drawings illustrates a packet
network 30, for example, the Internet, to which the users are connected
via telephone to packet adapters 10 or 400. It is to be noted that Figure
2 will be further described hereinafter with a view to illustrate some of the
various possibilities of the telephone to packet adapters 10 and 400.
A first user 32 is connected to the packet network 30 via
a first service provider 34 and a telephone line 36. The first service
provider 34 has a conventional Network Access Server 38 provided with
conventional modems (not shown) to interconnect its clients, for example
first user 32, to the packet network 30. The first user 32 has a telephone
to packet adapter 10a, a conventional modem 40 connected to the packet
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rietwork 10 port 16a, and a telephone set 42 connected to the telephone
port 12a. It is to be noted that both the Local Area Network port 14
(not shown) and the Local Area Network port 13a of the adapter 1 Oa are
not used.
5
It is to be noted that the telephone set 42 could be
replaced by a Local Area Network (not shown) connected to the Local
Area Network port 13a to therefore enable telephone calls, for example,
modem calls, from the Local Area Network to be routed to the packet
10 network 30.
Figure 2 also illustrates a second service provider 44
connected to the packet network 30 via an Internet server 46 and
including a telephone to packet adapter 400b interconnecting the Internet
server 46 and a telephone line 48, the purpose of which will be described
hereinafter with reference to Figure 5. More specifically, the server 46 is
connected to the Local Area Network 10 port 13b of the telephone to
packet adapter 400b and the telephone line 48 is connected to the 10
port 14b of the telephone to packet adapter 400b. It is to be noted that
the 10 port 12b is not used.
Of course, the telephone to packet adapter 400b of
Figure 2 could advantageously be provided with more than one telephone
line 10 ports 14b allowing the telephone to packet adapter 10b to be
connected to more than one telephone line. Indeed, this would allow the
second service provider 44 to interconnect more than two users
simultaneously.
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It is also to be noted that the telephone to packet
adapter 400b of Figure 2 could be replaced by a telephone to packet
adapter 10 as illustrated in Figure 1. If this is the case, the packet
network 10 port 16 will not be used.
5
The packet network 30 is also connected to a server 50
of a cable company 52 providing Internet services to its clients, for
example second user 54, via a conventional television cable 58
connected to the server 50 via adequate circuitry (not shown) known in
10 the art.
The second user 54 is equipped with a cable modem 60
connected to the conventional television cable 58 and a telephone to
packet adapter 400c interconnecting the cable modem 60 and a
telephone set 62. The telephone to packet adapter 400c is also
connected to a telephone line 64. More specifically, the cable modem 60
is connected to the Local Area Network 10 port 13c, the telephone 62 is
connected to the t0 port 12c and the telephone line 64 is connected to
the 10 port 14c. The telephone to packet adapter 400c therefore
considers the cable modem 60 as a Local Area Network interconnecting
the telephone to packet adapter 400 to the packet network 30
Finally, Figure 2 also illustrates a third user 66 equipped
with a telephone set 68 connected to a conventional telephone line 70.
Turning now to Figures 3-5, three different methods of
use of the telephone to packet adapters 10 and 400 will be described.
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Figure 3 generally illustrates the steps taken when the
second user 54 wants to reach another person.
After the telephone to packet adapter 400c is started
(step 100) and initialised (step 102), the system waits until the second
user 54 picks up the handset of the telephone set 62 and dials a
telephone number (step 104).
The agent software of the telephone to packet adapter
400c then verifies if the dialled telephone number is present in a
database contained in the controller circuit 20 (Figure 6) (Step 106). This
database contains a list of the telephone numbers that may be accessed
via the packet network 30.
If the dialled telephone number may not be accessed via
the packet network 30, the agent software of the telephone to packet
adapter 400c routes the telephone set 62 to the telephone line 64 and
dials the telephone number (step 108). The telephone number must
therefore be conventionally dialled over a telephone line to establish the
connection. This will be the case, for example, when the number dialled
is local or when there is no service provider similar to the second service
provider 44 in the area of the number dialled.
If the dialled number is present in the database, the
agent software then determines if the iP address corresponding to this
telephone number is in its database (step 110). If it is not the case, the
agent software interrogates the Internet server 50 of the cable company
52 (or any other server having a correspondence table between IP
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addresses and telephone numbers) to find the required IP address (step
112). When this is done, the agent software establishes the connection
between the second user 54 and the other user (for example the first user
32) (step 114).
The two connected users may then communicate
normally in full duplex since the conversation is bidirectionally digitised,
transformed into packets and transferred via the packet network 30 to the
other user where it is converted back into an analog signal and supplied
to the handset. Indeed, if the second user 54 is in communication with
the first user 32, the telephone to packet adapter 10a will convert back
the packets to an analog signal. Similarly, if the second user 54 calls the
third user 66, the telephone to packet adapter 400b will do the required
conversion.
The telephone to packet adapter 400c then waits until
the communication is broken (step 116) and then returns to step 104.
An advantage of the above mentioned set of
preestablished rules is that the second user 54 may either be
transparently in communication with conventional telephone users and
users of the present invention. Another advantage, is the possibility to
route all the calls to the telephone line 64 should the connection to the
packet network 30 via the cable company 52 be inactive, therefore
providing a PSTN fallback.
It is to be noted that instead of using the telephone set
62, the second user could connect a LAN (not shown) to the 10 port 13c
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arid connect the cable modem 60 to the LAN to therefore call another
user similarly equipped through the steps described hereinabove.
Figure 4 of the appended drawings generally illustrates
the steps taken when the first user 32 wants to reach another user.
Each step 200, 202, 204, 206, 208, 210, 214 and 216
is respectively identical to corresponding step 100, 102, 104, 106, 108,
110, 114 and 116 of Figure 3. Thus, for concision purposes, the
description of these steps will not be repeated hereinbelow.
Since the first user is not connected to the Internet via
a cable company, the Internet server 38 of the first Internet service
provider 34 (or any other server having a table of the IP addresses vs
telephone numbers) is interrogated in step 212.
A step 218 has been added between step 206 and 210
to instruct the modem 40 to connect to the service provider 34.
Therefore, according to the above-described set of
rules, the telephone line interface 24 is routed to the PSTN if the dialled
number is not in the database and routed to the packet network if the
dialled number is in the database
Again, it is to be noted that instead of using the
telephone set 42, the first user could connect a PC (not shown) or a LAN
(not shown) to the 10 port 13 and call another user similarly equipped
through the steps described hereinabove.
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Finally, Figure 5 of the appended drawings illustrates
another use of the telephone to packet adapter 10 of Figure 1. This
application is advantageous to reduce the long distance costs of the user.
The general principle is to detect if the telephone
number dialled by the user is a long distance number and to do a routing
of the call to a service provider (for example the second service provider
44 in Figure 1 ) in the area of the telephone number to therefore prevent
any long distance charges to the user if it is so. Of course the service
provider 44 is equipped with a telephone to packet adapter 400b that may
dial a local number via a telephone line 48.
Again, each step 300, 302, 304, 308 and 316 is identical
to the corresponding step 100; 102, 104, 108 and 116 of Figure 1 and
described hereinabove. Thus, for concision purposes, the description of
these steps will not be repeated hereinbelow.
In step 306, the telephone to packet adapter determines
if the telephone number dialled is a long distance number. If this is not
the case, step 308 is done as mentioned above.
If the telephone number dialled is a long distance
number (for example the telephone number of the third user 66), the
software agent of the telephone to packet adapter searches a database
(located in the controller circuit 20 or in an Internet server) to find the IP
address of a service provider equipped with a telephone to packet
adapter (for example the second service provider 44) in the area of the
telephone number dialled (step 320).
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The telephone to packet adapter then connects with this
service provider 44 gives its own IP address and the telephone number
of the third user 66 (step 322).
5 The telephone to packet adapter 400b of the second
service provider 44 then takes the telephone line 48 and dials the
received telephone number to establish the communication with the third
user (step 324).
10 Again, the use of the telephone to packet adapter 400
is transparent to the user since only one number is dialled. Also, the
above-described set or preestablished rules enables the user of the
present invention to communicate with a user of a conventional
telephone.
It is to be noted that it would also be possible to make
a local call to a user of a conventional telephone by using a local service
provider equipped with a telephone to packet adapter to do local calls.
This way, the second user 54, for example, would not require a
conventional telephone line to either receive or place local calls since
these calls could reach the second user 54 via the cable 58.
It is to be noted that modems could be integrated with
the telephone to packet adapter 10.
It is also to be noted that the controller circuit 20 of the
telephone to packet adapters 10 and 400 may generate a dial tone to
locally simulate the conventional dial tone sent to the AID DIA Full duplex
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interface 18. The aforementioned controller circuit 20 can also generate
other types of dial tones such as, for example, audio files.
As will be easily understood by one skilled in the art, the
agent software running in the controller circuit 20 of the telephone to
packet adapters 10 and 400 may advantageously include supplementary
features. For example, once an Internet server is interrogated to link an
IP address to a telephone number, the control circuit 20 may keep this
information in a database for future references in view of decreasing the
required connection delays. Similarly, speed dial numbers may be
assigned to such kept IP addresses.
Also, it is to be noted that the flow diagrams illustrated
in Figures 3-5 are schematised and that actual flow diagrams would be
a lot more complex and would include other rules for routing the calls.
For example, if the telephone to packet adapter detects that an
emergency number (911 in North America) has been dialled, it will
automatically take the telephone line and dial this emergency number.
Furthermore, it is to be noted that the flow diagrams '
illustrated in Figures 3-5 are not mutually exclusive. Indeed, the software
agent may determine how to route a call depending on the interfaces that
are connected to external devices and on users preferences, for example.
Therefore, the software agent embedded in the
controller circuit 20 is used to compute a route based on information
acquired or stored locally as welt as information acquired from a network
server. A calling method is derived from these rules and is used to
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determine which interfaces will be involved in the process of completing
the call. The appropriate route is triggered from the embedded software
agent running in a central processing unit of the controller circuit 20. The
embedded software agent may decide to exchange route information with
an intelligence server located on the network in order to make optimal
routing decisions. The embedded software agent will decide when it is
appropriate to select whether to use the packet network interface or the
telephone network interface to carry through a call. This method permits
of using a dedicated connection to a packet network in the home as a
mean for automatically diverting some telephone calls through a least
cost route.
As will be easily understood by one skilled in the art the
above-described invention provides many advantages, such as, for
example:
the use of an alternative packet-switched network
instead of a conventional telephone line to make telephone calls;
it does not impose on the end user a different usage
habit;
it is fully transparent to the end user;
it is possible to concurrently transmit many types of data
between users. For example, two users could be in a conversation via
telephone sets hooked to respective 10 ports 12 and transfer data from
Personal Computers connected to respective 10 ports 13; and
it provides a PSTN fallback.
It is also to be noted that the telephone set hooked up
to the apparatus sees the apparatus as its first telephone switch, which
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can potentially provide more services than the PSTN telephone switch,
due to its connectivity to the packet network, the services offered in the
packet network and due to the level of programmability that is possible
in the apparatus.
As will be apparent to one skilled in the art, the
telephone to packet adapters 10 and 400 may be designed to operate
with any type of PSTN telephone line such as, for example, ISDN, HFC
Cable Telephony, Wireless Local Loop, wireline, wireless digital or
analogue.
Although the telephone to packet adapter 10 of Figure 1
is shown provided with only one of each interfaces 18, 23, 24 and 26, it
would be within the reach of one skilled in the art to design a telephone
to packet adapter provided with more than one of these interfaces if
required by a particular application.
Although the present invention has been described
hereinabove by way of preferred embodiments thereof, it can be
modified, without departing from the spirit and nature of the subject
invention as defined in the appended claims.
