Note: Descriptions are shown in the official language in which they were submitted.
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PROCESSOR, SYSTEM AND METHOD FOR PROVIDING CALL BLOCKING
IN A PACKET NETWORK BASED TELEPHONE SYSTEM
This is a division of co-pending Canadian Patent
Application Serial No. 2,260,476, which was filed on
January 26, 1999.
TECHNICAL FIELD OF THE INVENTION
The present invention is directed, in general, to
telecommunications and, more specifically, to a system
and method for providing advanced calling features, such
as call forwarding and call blocking, to a packet
network-based telephone, such as an Internet telephone,
and a packet network that employs the system or the
method.
BACKGROUND OF THE INVENTION
Call forwarding and call blocking are well known
telephony services provided to subscribers by a local
exchange carrier in circuit switched networks.
Traditionally, call forwarding allows a subscriber (or
user) selectively to "program" an incoming call to be
forwarded to another communication device; call blocking,
on the other hand, prevents an incoming or outgoing call
from being completed.
As previously mentioned, call forwarding is a
generally recognized calling feature provided in circuit
switched networks and, as such, has been the subject of
many prior art references. For instance, U.S. Patent
No. 5,027,384, entitled "Personalized Automatic Call
Routing", by Sanford J. Morganstein, issued
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June 25, 1991, discloses a system where the subscriber
can preprogram the communication system to provide
personalized voice responses and alternate destinations
to assist the calling party in completing the call.
Additionally, U.S. Patent No. 5,442,691, entitled "Method
and Apparatus for Call Routing in Switched Digital
Networks Using Call Control Tables", by Steven Price, et
al., provides tables of call control information to
facilitate the routing of calls in a switched digital
network.
SUMMARY OF THE INVENTION
Internet telephone, systems for providing call
processing features (e.g., call forwarding or:call
blocking) to the UCD. The present invention therefore
adapts call processing techniques employed in circuit
switching systems to packet-based networks. In one
embodiment, the present invention: (1) determines that a
call composed of a stream of continuous media
communication packets and associated with the UCD
requires a specified alternative processing and
(2) causes the continuous media communication data
packets associated with the call to be processed in
accordance with the specified alternative processing.
The call forwarding system or the call blocking
system may be directly connectible with the UCD or may be
directly connectible with a point of presence (POP) of
the packet network (such as an Internet Service Provider,
or ISP). "Directly connectible", for purposes of the
present invention, is defined as being directly
associated with or a part of. For example, one or both
of the systems may be in a user's telephone or computer
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UCD. One or both of the systems may be at the user's
ISP, such that they may operate even when the user's UCD
is not connected to the packet network.
In one embodiment, the call forwarding system stores
call forwarding criteria and forwards incoming calls
based on the call forwarding criteria. In one
embodiment, the call blocking system receives information
pertaining to a potential call with another party and
blocks completion of the potential call based on a
comparison of stored call blocking criteria with the
information.
In accordance with one aspect of the present
invention there is provided for use with a user
communication device (UCD) that communicates over a
packet network by transmitting and receiving streams of
continuous media communication data packets, a processor
for providing a call blocking feature to said UCD that
executes instructions to: receive a stream of associated
continuous media communication data packets relating to a
potential call with another party; and block completion
of said potential call based on a comparison of call
blocking criteria stored by a user of said UCD with
information derived from said stream.
In accordance with another aspect of the present
invention there is provided for use with a user
communication device (UCD) that communicated over a
packet network by transmitting and receiving streams of
continuous media communication data packets, a system for
providing a call blocking feature to said UCD,
comprising: means for receiving a stream of associated
continuous media communication data packets relating to a
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potential call with another party; and means for blocking
completion of said potential call based on a comparison
of call blocking criteria stored by a user of said UCD
with information derived from said stream.
In accordance with yet another aspect of the present
invention there is provided a method of providing call
blocking to a user communication device (UCD) that
communicates over a packet network by transmitting and
receiving streams of associated continuous media
communication data packets that are associated with said
UCD, comprising the steps of: receiving a stream of
associated continuous media communication data packets
relating to a potential call with another party; and
blocking completion of said potential call based on a
comparison of call blocking criteria stored by a user of
said UCD with information derived from said stream.
The present invention, taken in conjunction with the
invention described in co-pending Canadian Patent
Application Serial No. 2,260,476, which was filed on
January 26, 1999 will be discussed in detail, hereinbelow
with the aid of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present
invention, reference is now made to the following
descriptions taken in conjunction with the accompanying
drawings, in which:
FIG. 1 illustrates an embodiment of a packet network
providing an environment for a system constructed
according to the principles of the present invention;
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FIG. 2 illustrates an embodiment of a data packet
assembled according to the present invention;
FIG. 3 illustrates a block diagram of an exemplary
computer providing an environment within which the system
5 of the present invention may be employed and implemented;
FIG. 4 illustrates a flow chart of an embodiment of
a packet interception routine according to the principles
of the present invention;
FIG. 5 illustrates a flow chart of an embodiment of
a call blocking routine according to the principles of
the present invention;
FIG. 6 illustrates a flow chart of an embodiment of
a call forwarding routine according to the principles of
the present invention; and
FIG. 7 illustrates a flow chart of a related
embodiment of the call forwarding routine of FIG. 6.
DETAILED DESCRIPTION
Referring initially to FIG. 1, illustrated is an
embodiment of a packet network, generally designated 100,
providing an environment for a system constructed
according to the principles of the present invention.
The packet network 100, e.g., the Internet, facilitates
the transmission of data in the form of data packets, or
datagrams, between a user station and a single station,
in the case of a unicast, or between a user station and a
plurality of stations, as with a multicast. The packet
network 100 includes a user station 130, typically a
processor, such as a personal computer (PC), that is
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coupled to a data storage device 135, e.g., an external
hard disk. The system of the present invention is not
limited for use with a data storage device such as
external physical devices or even the presence of such
devices physically connected to the user station 130.
The system of the present invention contemplates that the
user station 130 is able to access a data storage device
at either the user station 130 or at a remote location,
or both.
The user station 130 is also coupled to an access
node 140, or point of presence (POP), that provides a
gateway to the packet network 100. The access node 140
may be a packet network service provider, such as an
Internet service pProvider (ISP), and is shown coupled to
a data storage device 145 analogous to the data storage
device 135. The presence of the access node 140 is not
necessary to the practice of the present invention as the
user station 130 is equipped to communicate directly to
the packet network 100 without requiring an intermediate
interface. A station 120 and a plurality of alternate
stations 150 are also coupled to the packet network 100.
The station 120 and the plurality of alternate stations
150 are typically user communication devices (UCDs), such
as packet telephones, voice mailboxes, or pagers.
The user station 130 communiGates with the station
120 or alternate stations 150 by ser.Lding data packets via
the packet network 100. Further information about packet
network architectures and transmission of data packets
may be found in "Data Network Design", by Darren L.
Spohn, McGraw-Hill, Inc. (1993).
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Turning now to FIG. 2, illustrated is an embodiment
of a continuous media communication data packet 210
assembled according to the present invention. The data
packet 210, e.g., an Internet Protocol (IP) packet,
includes a header 220, data 230 and other information,
such as an identifier or options associated with the data
packet. Included in the header 220 are source 250 and
destination 260 information. The data packets 210
contain complete addressing information and may be split,
or fragmented, into smaller packets. The fragmentation
of the data packets 210 will permit a large data packet
to travel across a packet network which can only handle
smaller data packets.
It is not necessary that the source and destination
information 250, 260 be contained only in the header 220
of the data packet 210; the source and destination
information 250, 260 may also reside in other locations
within the data packet 210. Furthermore, the source and
destination information 250, 260 may include not only the
addresses of the source and destination, but also other
identifiers, such as the identity of individual at the
source or destination, or both.
Turning now to FIG. 3, illustrated is a block
diagram of an exemplary computer, generally designated
300, providing an environment within which the system of
the present invention may be employed and implemented.
The computer 300 includes processing circuitry 310, e.g.,
having at least one conventional processor, conventional
volatile memory 320, e.g., random access memory,
non-volatile memory 330, e.g., a hard disk drive, and a
UCD 360. The UCD 360 may be separate devices, such as a
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microphone, speakers and associated voice encoding and
decoding software, or a conventional telephone that has
been adapted for use with the present invention. The
processing circuitry 310, volatile memory 320 and
non-volatile memory 330 are associated with each other
and cooperatively operate to execute the system of the
present invention. The computer 300 may further include
an input/output device 340, such as a keyboard, and a
display device 350, such as a video monitor. The
keyboard may be used to control the execution of the
process associated with the system of the present
invention in the computer 300, and a video monitor may be
used to view the results thereof.
The principles of the present invention are not
limited to a particular processing environment, but may
be implemented in any processing system architecture,
including, without limitation, microcomputers, e.g.,
personal computers, and main-frame computers.
Conventional processing system architecture is discussed
in "Computer Organization and Architecture", by William
Stallings, MacMillan Publishing Co. (3rd ed. 1993), and
conventional processing system network design is
discussed in "Data Network Design", by Darren L. Spohn,
McGraw-Hill, Inc. (1993).
In one embodiment of the present invention, a system
for providing a call blocking feature is embodied in a
sequence of instructions executable in the computer 300.
The call blocking process includes a packet interception
routine that monitors a particular user station for
outgoing or incoming calls. Upon detection of a call,
incoming or outgoing, the packet interception routine
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then determines the identity of the calling and called
parties and provides this information to a call blocking
routine. The call blocking routine proceeds to decide if
the call, incoming or outgoing, should be terminated
based on the information provided by the packet
interception routine. A more specific embodiment of the
packet interception routine and the call blocking routine
will be described with respect to FIGS. 4 and 5.
In another embodiment of the present invention, a
system for providing a call forwarding feature is
embodied in a sequence of instructions executable in the
computer 300. The call forwarding routine receives an
incoming call and determines the identity of the calling
and called parties. The call forwarding routine provides
the identities of the calling and called parties to a
call forwarding criteria routine that compares the
provided information to entries in a call forwarding
directory. The call forwarding directory contains
routing information associated with calling entities and
provides alternate destinations to the call forwarding
routine, to complete the incoming call. A more specific
embodiment of the call forwarding routine and the call
forwarding criteria routine will be described with
respect to FIGS. 6 and 7. Those skilled in the art
understand, however, that the foregoing embodiments and
the systems of the present invention, in general, may
also be implemented in hardware, firmware, software, or
any combination thereof.
Turning now to FIG. 4, illustrated is a flow chart
of an embodiment of a packet interception routine
according to the principles of the present invention.
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The process begins at a start step 405 with an access
node monitoring a packet network and user station for any
outgoing or incoming calls. At a detect call step 410,
the access node detects a call. Outgoing calls from the
5 user station are usually detected when the user station
requests a connection to the packet network. Similarly,
incoming calls are usually detected when data packets are
received at a station serving as the destination. Upon
detection of a call, incoming or outgoing, source and
10 destination information contained in the header of the
data packets are extracted and the data packets are
placed in a buffer, e.g., a memory device associated with
the access node, pending a request from the call blocking
routine to transmit the data packets. The extracted
source and destination information are then provided, at
a provide information step 415, to the call blocking
routine.
Turning now to FIG. 5, illustrated is a flow chart
of an embodiment of a call blocking routine according to
the principles of the present invention. The call
blocking routine is initiated, at a receive information
step 520, with the acceptance of the source and
destination information of the data packets. At an
incoming or outgoing decisional step 525, it is
determined whether the call is an incoming or outgoing
call. This is accomplished by comparing the source
identifier with the station identifier. If the source
and station identifiers are the same, the call is an
outgoing call.
If the determination at the incoming or outgoing
step 525 is that the call is an outgoing call, control
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passes to a call blocking enabled decisional step 530 to
determine if call blocking is enabled for the calling
station. The determination of whether call blocking is
enabled may be accomplished by accessing a particular
memory location, which may be associated with an enable
flag or other identifier, which would determine if the
bit has been set, i.e., a logic "1". If call blocking
has not been enabled, the call blocking routine, at a
complete call step 535, transmits a request to the access
node to release the buffered data packets and complete
the connection.
If it is determined at the call blocking enabled
step 530, however, that call blocking is enabled, control
passes to a selective call blocking enabled decisional
step 540 to determine if selective call blocking has been
activated for the called station, i.e., destination, by
comparing the called station with a call blocking
criteria that has been preestablished. Selective call
blocking is to distinguish from the call blocking enabled
at step 530. The call blocking enabled decisional step
530 determines if the call blocking feature has been
activated for the calling station whereas selective call
blocking determines if calls to the called station is to
be blocked. The station user generally creates call
blocking control entries that may be used by the
application programs running at the local station
processor, the access node processor, the remote
processors accessed through the packet network or any
stations of the packet network which are connected to the
remote processors. An outgoing call blocking directory
may be created with each entry comprising a name of a
specific destination and associated call blocking control
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information. An example of a call control table is
disclosed in Steven Price, et al. The destinations in
the outgoing call blocking directory table may include,
for instance, the continuous media communication data
packet source address, the continuous media communication
data packet destination address, the identity of the
calling party, the automatic number information (ANI)
associated with the call and the identity of the called
party. The call blocking control information may include
a time period, such as a day of week or time of'day, when
calls to the associated destinations of the call blocking
control information are not to be completed, i.e.,
blocked.
To illustrate, a station user, e.g., Mother with
child A and child B, may define the call blocking
directory whereby calls initiated by Mother are never
blocked and calls to predetermined destinations initiated
by child A or child B are selectively blocked depending
on the call blocking control information associated with
each child. The identification of the current station
user, e.g., Mother, child A or child B, may be
accomplished with a "logon" procedure using identifiers,
such as user I.D. and passwords. Also, passwords or
identifiers may be employed to prevent the unauthorized
additions and deletions to the call blocking directory.
Additionally, both static and dynamic call blocking
directory tables may be employed. In the former, all the
entries are fully defined before the initiation of any
calls. In the latter, destinations and call blocking
control information may be added and deleted dynamically
or alternatively may be enabled or disabled, as required
and not only before calls are initiated. The table
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entries are the call blocking criteria used at the
selective call blocking enabled step 540 to determine if
call blocking has been activated for the called station.
If at the selective call blocking enabled step 540,
it is determined that selective call blocking for that
particular destination has not been enabled or does not
exist, the call blocking routine, at a complete call step
545, transmits a request to the access node to release
the buffered data packets and complete the connection.
However, if at the selective call blocking enabled step
540, it is determined that selective call blocking for
that particular destination has been enabled, the call
blocking routine, at a block call step 550, transmits a
request to the access node to discard the buffered data
packets and deny the station access to the packet
network.
Returning to the incoming or outgoing step 525, if
it is determined that the call is an incoming call,
control passes to a call blocking enabled decisional step
555 to determine if call blocking is enabled for the
called station. The determination of whether call
blocking is enabled may be accomplished by accessing a
particular memory location, which may be associated with
an enable flag or other identifier, which would determine
if the bit has been set, i.e., a logic "1". If call
blocking has not been enabled, the call blocking routine,
at a complete call step 560, transmits a request to the
access node to release the buffered data packets and
complete the connection.
If it is determined at the call blocking enabled
step 555, however, that call blocking is enabled, control
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passes to a selective call blocking enabled decisional
step 565 to determine if selective call blocking has been
activated for the calling station, i.e., source, by
comparing the calling station with the call blocking
criteria that has been preestablished. Selective call
blocking is to distinguish from the call blocking enabled
at step 555. The call blocking enabled decisional step
555 determines if the call blocking feature has been
activated for the called station whereas selective call
blocking determines if calls from the calling station is
to be blocked. An incoming call blocking directory,
similar to the outgoing call blocking directory described
previously, is defined by the station user with entries
corresponding to specific sources and associated call
blocking control information.
If at the selective call blocking enabled step 565,
it is determined that selective call blocking for that
particular destination has not been enabled or does not
exist, the call blocking routine, at a complete call step
570, transmits a request to the access node to release
the buffered data packets and complete the connection.
If at the selective call blocking enabled step 565,
however, it is determined that selective call blocking
for that particular destination has been enabled, the
call blocking routine, in a block call step 575,
transmits a request to the access node to discard the
buffered data packets and ignore, i.e., do not transmit,
data packets from that source to the station.
Turning now to FIG. 6, illustrated is a flow chart
of an embodiment of a call forwarding routine according
to the principles of the present invention. The process
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begins at a start step 605 with an access node monitoring
a packet network for incoming calls. At a call detected
step 610, an incoming call is detected when data packets
are received identifying the user station as the
5 destination.
Upon detection of an incoming call, control passes
to a call forwarding enabled decisional step 615 to
determine if call forwarding has been enabled for the
called station, i.e., user station. The determination of
10 whether call forwarding is enabled may be accomplished by
accessing a particular memory location, associated with
an enable flag, to determine if the bit has been set,
i.e., a logic "1". If call forwarding has not been
enabled, the call forwarding routine, in a continue
15 transmission step 620, transmits a request to the access
node to continue to transmit the data packets to the user
station.
However, if it is determined, at the call forwarding
enabled step 615, that call forwarding is enabled, source
and destination information contained in the header of
the data packets are extracted, at an extract information
step 625, and the data packets are placed in a buffer,
typically a memory device associated with the access
node, e.g., data storage device, pending a request from
the call forwarding criteria routine to transmit the data
packets to an alternate destination. The call forwarding
routine provides the extracted source and destination
information, at a provide information step 630, to the
call forwarding criteria routine and control passes to a
wait for request step 635, whereby the call forwarding
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routine waits for a request from the call forwarding
criteria routine.
When a request is received by the call forwarding
routine, at a what is request decisional step 640, it is
determined if the request is to continue transmitting
data packets to the called station or to reroute the data
packets to an alternate destination. If it is determined
that the request is to continue transmitting the data
packets to the user station, the access node continues to
transmit the data packets to the user station at a
continue transmission step 645.
If it is determined, however, that the data packets
are to be rerouted to an alternate destination, the call
forwarding routine, at a forward to alternate destination
step 650, substitutes the destination address in the
header of the data packets with the alternate destination
address provided by the call forwarding criteria routine.
The data packets with the substituted destination address
are then retransmitted over the packet network.
Turning now to FIG. 7, illustrated is a flow chart
of a related embodiment of the call forwarding routine of
FIG. 6. The call forwarding routine: is initiated at a
receive information step 755, with the acceptance of the
source and destination information contained in the
received data packets. Control passes to a selective
call forwarding enabled decisional step 760 to determine
if selective call forwarding has been activated for the
called station, i.e., destination, by comparing the
calling station with the call forwarding criteria that
has been preestablished. A call routing directory for
incoming calls is configured and used in a similar way as
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the call blocking directory described previously. The
call routing directory contains the call forwarding
criteria and is defined by the station user with entries
corresponding to specific sources and associated call
routing control information to alternate destinations.
The call routing directory may include the continuous
media communication data packet source address, the
continuous media communication data packet destination
address, the identity of the calling party, the automatic
number information (ANI) associated with the call and the
identity of the called party. The call routing control
information may include a time period, such as a day of
week or time of day, when calls to an associated
alternate destination of the call routing control
information are to be accomplished, i.e., forwarded.
Additionally, the alternate destination addresses may
specify an endpoint that may be a second telephone, a
voice mailbox, a pager or another computer.
If, at the selective call forwarding enabled step
760, it is determined that selective call routing for
that particular source has not been enabled or does not
exist in the call routing directory, the call forwarding
routine, in a default destination decisional step 765,
determines whether a default destination has been
specified in the call routing directory. If no default
destination has been specified, the call forwarding
routine, at a request continued transmission step 770,
transmits a request to the access node to continue to
transmit the data packets to the user station. If a
default destination has been specified, however, the call
forwarding criteria routine, at a provide default
destination step 775, provides the default destination
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address along with a request to the call forwarding
routine to route the call to the destination address.
If it is determined, however, that selective call
routing for that particular source is enabled, i.e., the
call routing directory has an entry for the source and
associated alternate destination(s), the call forwarding
criteria routine, at a provide alternative destination
step 780, provides the associated alternate destination
address(es) along with a request to the call forwarding
routine to route the call to the alternate destination
address (es) .
Although the present embodiment: describes that the
packet interception routine, call blocking routine, call
forwarding routine and call forwarding criteria routine
are resident in data processing and storage circuitry of
the access node, the systems of the present invention are
not limited to a particular device or location. The
packet interception, call blocking, call forwarding and
call forwarding criteria routines may also reside
together in the user station or the user station's data
storage device or separately at different locations.
The foregoing has outlined preferred and alternative
features of the present invention so that those skilled
in the art may better understand the detailed description
of the invention. Those skilled in the art should
appreciate that they can readily use the disclosed
conception and specific embodiment as a basis for
designing or modifying other structures for carrying out
the same purposes of the present invention. Although the
present invention has been described in detail, those
skilled in the art should understand that they can make
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various changes, substitutions and alterations herein
without departing from the spirit and scope of the
invention in its broadest form.
