Field of the invention
The present disclosure relates to a communication system and
particularly to a method and apparatus for forking a calling request to one
of a plurality of registered called user addresses.
Background of the invention
In an 3rd Generation Partnership Project (3GPP) IP Multimedia
Subsystem (IMS), a Serving-Call Session Control Function (S-CSCF)
entity can support a public user identity with a plurality of registered
contact addresses, that is, a user can be associated concurrently with a
plurality of contact addresses, e.g., a cell phone address, a fixed phone
address, a voice mailbox address, etc.. When a public user identity is
associated with a plurality of registered contact addresses, the S-CSCF
shall support forking so that a Session Initiation Protocol (SIP) request
pointing to the public user identity can be forwarded to the plurality of
registered contact addresses.
In a parallel forking scheme, the SIP request is transmitted .e concurrently to the plurality of registered addresses associated with the
public user identity, and then all of user equipments corresponding to the
respective registered contact addresses will ring substantially at the same
time.
In a sequential forking scheme, one of the plurality of registered
addresses associated with the public user identity is determined according
to numerical values corresponding respectively to the plurality of
registered addresses, and the SIP request is forked to the determined
registered address, and then only the user equipment corresponding to the
determined registered address will ring.
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Summary of the invention
The inventors have identified that in the existing forking scheme, the
forking scheme is the same for different calling numbers. However a user
wishes to enable a specific forking scheme to be applied to a specific
category of calling numbers in some application scenarios. For the
incoming call from a family member, for example, the user wishes to
enable a calling request to be preferentially forked to a registered address
corresponding to a fixed phone so that the user can communicate with the
family member for a long time period without worrying about the
radiation problem due to communication using a cell phone. In another
example, for a "spam" call, e.g., a commercial surveyor a promotion call,
the user wishes to enable a calling request to be preferentially forked to a
registered address corresponding to a voice mailbox to thereby alleviate
or avoid the negative effect of the "spam" call on his or her life.
With understanding of the background of the invention and of the
foregoing problem, it will be of great benefit if the forking scheme
applied for some calling numbers can be different from that of other
calling numbers.
In order to address the foregoing concern, according to an embodiment
of an aspect of the invention, there is provided a method, in a network
device, of forking a calling request to a first registered called user address
among a plurality of registered called user addresses, the plurality of
registered called user addresses sharing a public user identity code, the
method comprising the steps of:
A. obtaining forking-related information, the forking-related
information corresponding to the public user identity code and
representing a forking order relationship between at least one calling
number and the plurality of registered called user addresses;
B. receiving the calling request from a calling user equipment, the
calling request including the public user identity code, and the calling
user equipment corresponding to one number of said at least one calling
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number;
c. determining the first registered called user address among the
plurality of registered called user addresses according to the number of
the calling user equipment and the forking-related information
corresponding to the public user identity code; and
D. forking the calling request to the first registered called user
address.
If a calling number is recorded in the forking-related information, then
the registered address of a forking destination of a calling request from
the calling number is determined taking into account the forking-related
information representing a forking order relationship between at least one
calling number and a plurality of registered called user addresses, so the
calling request of the calling number can be forked to the corresponding
registered address in a forking scheme related to the forking-related
information. In other words, the forking scheme of a calling request for a
calling number recorded in the forking-related information may be
different from that of a calling number which is not recorded in the
forking-related information. In this way, a specific forking scheme can be
adopted for some specific numbers to thereby satisfy a personalized
demand of the user.
Optionally each of said at least one calling number corresponds
respectively to only one of the plurality of registered called user addresses,
that is, a calling number is associated with only one registered called user
address. Since a calling number is associated with only one registered
called user address, forking operations of the network device can be
simplified and it will be convenient for a user to use.
According to an embodiment of another aspect of the invention, there
is provided a forking apparatus, in a network device, for forking a calling
request to a first registered called user address among a plurality of
registered called user addresses, the plurality of registered called user
addresses sharing a public user identity code, the forking apparatus
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comprIsmg:
a first device configured to obtain forking-related information, the
forking-related information corresponding to the public user identity code
and representing a forking order relationship between at least one calling
number and the plurality of registered called user addresses;
a second device configured to receive the calling request from a
calling user equipment, the calling request including the public user
identity code, and the calling user equipment corresponding to one
number of said at least one calling number;
a third device configured to determine the first registered called
user address among the plurality of registered called user addresses
according to the number of the calling user equipment and the
forking-related information corresponding to the public user identity code;
and
a fourth device configured to fork the calling request to the first
registered called user address.
The respective aspects of the invention will become more apparent
from the following description of embodiments.
Brief description of drawings
The foregoing and other features, objects and advantages of the
invention will become more apparent upon review of the following
detailed description of non-limiting embodiments taken with reference to
the drawings in which:
Fig.! is a flow chart of a method of forking a calling request to one of
a plurality of registered called user addresses according to an embodiment
of the invention;
Fig.2a to Fig.2d illustrate embodiments of the forking-related
information according to the invention;
Fig.3 is a flow chart of a method of forking a calling request to one of
a plurality of registered called user addresses according to another
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embodiment of the invention;
FigA is a flow chart of a method of obtaining the forking-related
information by a network device according to an embodiment of the
invention; and
Fig.5 is a schematic diagram of a forking apparatus according to an
embodiment of the invention.
Identical or like reference numerals denote identical or like
components throughout the drawings.
Detailed description of embodiments
Fig.l is a flow chart of a method according to an embodiment of the
invention.
According to an embodiment of an aspect of the invention, there is
provided a method, in a network device, of forking a calling request to a
first registered called user address among a plurality of registered called
user addresses.
A plurality of registered called user addresses share a public user
identity code, for example, a public user identity code is associated with a
plurality of registered called user addresses. The plurality of registered
called user addresses can include anyone of the following: an address
corresponding to a cell phone, an address corresponding to a fixed phone
and an address corresponding to a voice mailbox. The network device is
configured to fork a calling request and can be embodied in numerous
ways, for example, as an S-CSCF entity in an IMS system.
Referring to Fig.l, the method includes the step 110 in which the
network device obtains forking-related information. The forking-related
information corresponds to the public user identity code and represents a
forking order relationship between at least one calling number and the
plurality of registered called user addresses.
The network device can obtain the forking-related information in
numerous ways, for example, obtain the forking-related information from
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a user and store it in the network device or obtain the forking-related
information from another network device.
The forking-related information can be represented in numerous ways.
Fig.2a to Fig.2d illustrate embodiments of the forking-related information
according to the invention.
In an embodiment, each of the at least one calling number corresponds
respectively to only one of the plurality of registered called user addresses,
that is, a calling number is associated with only one registered called user
address. In the forking-related information as illustrated in Fig.2a,
PUBLIC_ID is a public user identifier, PRIVATE_ID is a registered called
user address sharing the public user identifier, and CALLING_PREFER is
a calling number preferentially forked to a corresponding registered
address. The forking-related information illustrated in Fig.2a includes
three registered called user addresses corresponding to the public user
identifier ivy.puid, where ivy.cell is the registered called user address
corresponding to a cell phone, ivy.pots is the registered called user
address corresponding to a fixed phone, and ivy.mailbox is the registered
called user address corresponding to a voice mailbox. Two calling
numbers corresponding to the registered called user address ivy.cell are
two cell phone numbers 13900296666 and 13905326666, that is, the
calling request of these two numbers will be forked to the registered
called user address ivy. cell. The calling number corresponding to the
registered called user address ivy.mailbox is a number with leading 800,
that is, the calling request of the number with leading 800 will be forked
to the registered called user address ivy.mailbox. Since a calling number
is associated with only one registered called user address, forking
operations of the network device can be simplified, and it will be
convenient for a user to use.
In a further embodiment, at least one of the at least one calling number
corresponds respectively to more than one of the plurality of registered
called user addresses, that is, a calling number is associated with more
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than one registered called user address. In the forking-related information
as illustrated in Fig.2b, CALLING_PREFER1 is a calling number initially
forked to a registered called user address, and CALLING_PREFER2 is a
calling number re-forked to another registered called user address if a user
equipment corresponding to the initially forked registered called user
address does not answer the calling request in a predetermined time
period. Corresponding to the forking-related information illustrated in
Fig.2b and taking a calling request from the calling number 13905326666
as an example, it will be forked initially to the registered called user
address ivy.pots and will be forked to the registered called user address
ivy. cell if there is no response in a predetermined time period.
In the foregoing two embodiments, the forking order relationship
between the calling number and the registered called user addresses is
listed per category of registered called user address. Optionally the
forking order relationship between the calling number and the registered
called user addresses can be listed per category of calling number, as the
forking-related information illustrated in Fig.2c and Fig.2d. The
forking-related information illustrated in Fig.2c and Fig.2d can play the
same role of forking, and the forking-related information illustrated in
Fig.2c and Fig.2d can play the same role of forking.
The method further includes the step 120 in which the network device
receives the calling request from a calling user equipment. The calling
request includes the public user identity code, and the calling user
equipment corresponds to one number of the at least one calling number.
The at least one calling number includes numbers of various types of user
equipments, e.g., a number of a cell phone, a number of a fixed phone,
etc.
The method further includes the step 130 in which the network device
determines the first registered called user address among the plurality of
registered called user addresses according to the number of the calling
user equipment and the forking-related information corresponding to the
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public user identity code.
The first registered called user address is the finally determined
registered called user address of a forking destination. The network device
can determine the forking-related information corresponding to the public
user identity code via the public user identity code in the calling request.
Since the forking order relationship between the at least one calling
number and the plurality of registered called user addresses is recorded in
the forking-related information, e.g., the forking-related information
illustrated in Fig.2a to Fig.2d, the network device can determine the
registered called user address to be forked to according to the
forking-related information.
The method further includes the step 140 in which the network device
forks the calling request to the first registered called user address.
A calling user which is not recorded in the forking-related information
can be forked in an existing forking scheme, e.g., parallel forking or
sequential forking. The relevant forking scheme shall be known to those
skilled in the art and a detailed description thereof will not be repeated.
A method of forking a calling request to one of a plurality of
registered called user addresses will be further described below taking an
IMS system as an example.
Fig.3 is a flow chart of a method of forking a calling request to one of
a plurality of registered called user addresses according to another
embodiment of the invention.
Referring to Fig.3, firstly a user equipment UE-o transmits a calling
request message INVITE to a Proxy-Call Session Control Function
(P-CSCF) entity P-CSCF-0 corresponding to the UE-o via the Session
Initiation Protocol (SIP).
Then the calling request IS forwarded to a Serving-Call Session
Control Function (S-CSCF) entity S-CSCF-t corresponding to the identity
(which can also be referred to as an identity code) of a destination user of
the calling request sequentially through a Serving-Call Session Control
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Function (S-CSCF) entity S-CSCF-0 corresponding to the UE-o and an
Interrogating-Call Session Control Function (I-CSCF) entity I-CSCF-t
corresponding to the identity of the destination user of the calling request,
wherein I-CSCF-t obtains the related information of S-CSCF-t through
inquiring a Home Subscriber Server (HSS).
Next S-CSCF-t determines the calling request to be forked to a UE-tl
corresponding to a registered called user address according to the
forking-related information and the number of UE-o and transmits the
calling request to UE-tl via a Proxy-Call Session Control Function
(P-CSCF) entity P-CSCF-tl corresponding to UE-tl. UE-tl reports
reception of the calling request through feeding back a message 100
Trying and reports ongoing processing of the calling request at UE-tl via
a progress report message 183 Prog.
Finally the calling request has no final response 2000K at UE-tl, so
S-CSCF-t forks the calling request again to UE-t2. S-CSCF-t can adopt
numerous ways for further forking, for example, perform forking
according to the forking-related information and the number of UE-o or
perform forking according to only numerical values corresponding to
UE-t2 and UE-t3. Finally the calling request is answered at UE-t2.
FigA is a flow chart of a method of obtaining forking-related
information by a network device according to an embodiment of the
invention.
Referring to FigA, S-CSCF obtains forking related information, e.g.,
the forking related information illustrated in Fig.2a to Fig.2d, from HSS
in the step 7 in a registration procedure of a user equipment UE.
The forking related information can be put in a user-data Attribute
Value Pair (AVP) of a Serving Assignment Answer (SAA) command. The
user-data attribute value pair including the forking related information can
be defined in the following XML language.

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ivy.cell

ivy.puid

13900296666
13905326666

O

1

O
O
INVITE

O
O
MESSAGE

O
O
SUBSCRIBE

O
1
INVITE

O
I
MESSAGE

1
1

11
From
"joe"

sip:AS l@homedomain.com
O