[DESCRIPTION]
[INVENTION TITLE] TELEPHONE SYSTEM BASED ON PRESENCE AND CALL ROUTING METHOD THEREOF
[TECHNICAL FIELD]
The present invention relates to a presence-based telephony system. More specifically, the present invention relates to a presence-based
telephony system for using a Voice over Internet Protocol (VoIP) terminal to
receive a call generated to a wired/wireless telephone number, and a call
routing method thereof.
[BACKGROUND ART] As the Internet has been popularized, usage of VolPs has also
increased. The VoIP allows calls to the existing wired or wireless networks
through a dedicated program installed in a computer, but the VoIP cannot
receive calls because it has no telephone number. To solve the problem, studies for assigning telephone numbers to the VolPs according to a VoIP number system have been progressed.
The Internet messenger which is very popular among Internet users
represents a system which uses the 3GPP Instant Messaging & Presence protocol (IMPP) to instantly transmit and receive text between computers on
the Internet. The system manages presence which indicates a user's current
status including the user's online access information, offline information, seat
occupation information, and busy information. The above-noted presence is
displayed to a buddy list of a person who has registered the user as a buddy
to thereby notify the person of a time when to send a message to the user. However, the IMPP of the Internet messenger system only provides
the message exchange service between computers and provides no further
various services such as a call service to the VoIP or the wired/wireless networks.
As to prior art, Korean published application No. 2003-90421 entitled
"Unified presence service system and method" by KT discloses a scheme
for managing presence of accesses to various communication service
providers by a same subscriber in a unified manner, but it fails to disclose usage of presence for call routing.
As to another prior art, Korean published application No. 2003-58557
entitled "Presence service providing method using SIP in mobile
communication packet network" by SKTelecom discloses a method for using
a Session Initiation protocol (SIP) to provide a presence service in the mobile
communication packet network, but it also fails to disclose usage of
presence for call routing.
As to another prior art, Korean published application No. 2003-68105
entitled "Device and method for providing Internet call reception switching
service in mobile communication system" by Jae-ryang Ko discloses a
system in which a mobile subscriber switches a call generated to the
subscriber's phone number not to a mobile station but to a soft phone or an
IP phone on the Internet and then answers the call, which however fails to disclose usage of presence for call routing.
[DISCLOSURE]
[TECHNICAL PROBLEM]
It is an advantage of the present invention to provide a presence-
based telephony system for using an IMPP presence concept and an existing wired/wireless communication telephone number to allow the usage
of VoIP, and a control method thereof.
[TECHNICAL SOLUTION]
In one aspect of the present invention, a telephony system based on
presence comprises: a wired/wireless telephone system for providing a call connection service to a wired/wireless telephone terminal; a Voice over Internet protocol (VoIP) gateway coupled between the wired/wireless
telephone system and the Internet, and providing a call connection service to
a VoIP terminal; and a presence server accessed to the wired/wireless telephone system, the VoIP gateway, and the VoIP terminal, and managing presence of a wired/wireless call service subscriber, wherein the
wired/wireless telephone system routes a call dialed to the subscriber to one
of the subscriber's wired/wireless telephone terminal and the VoIP terminal
accessed through the VoIP gateway according to presence information established in the presence server. In another aspect of the present invention, a call routing method in a telephony system based on presence comprises (a) receiving a call dialed by
a wired/wireless telephone terminal; (b) acquiring presence information of a
subscriber who will receive the dialing call; and (c) routing the dialing call to
one of the dialed subscriber's wired/wireless telephone terminal and the
VoIP terminal according to the acquired presence information.
[DESCRIPTION OF DRAWINGS]
FIG. 1 shows a block diagram of a presence-based telephony
system according to an exemplary embodiment of the present invention;
FIG. 2 shows a process for connecting a dialing call generated by a mobile station M1 to a VoIP terminal V1 in a presence-based telephony
system according to an exemplary embodiment of the present invention;
FIG. 3 shows a process for connecting a dialing call generated by a
VoIP terminal V1 to a mobile station M1 in a presence-based telephony system according to an exemplary embodiment of the present invention;
FIG. 4 shows a process for connecting a dialing call generated by a
mobile station M1 to another mobile station M2 in a presence-based
telephony system according to an exemplary embodiment of the present invention;
FIG. 5 shows a process for connecting a dialing call generated by a
VoIP terminal V1 to another VoIP terminal V2 in a presence-based telephony system according to an exemplary embodiment of the present invention;
FIG. 6 shows a process for registering and updating presence in a presence-based telephony system according to an exemplary embodiment of the present invention;
FIG. 7 shows a process for forwarding a call according to presence
in a presence-based telephony system according to an exemplary embodiment of the present invention; FIG. 8 shows a process for unregistering presence in a presence-
based telephony system according to an exemplary embodiment of the
present invention; and
FIG. 9 shows a block diagram of a presence-based cable intelligent
network system according to an exemplary embodiment of the present
invention.
[BEST MODE]
In the following detailed description, only the preferred embodiment
of the invention has been shown and described, simply by way of illustration
of the best mode contemplated by the inventor(s) of carrying out the invention. As will be realized, the invention is capable of modification in
various obvious respects, all without departing from the invention. Accordingly, the drawings and description are to be regarded as illustrative in
nature, and not restrictive. To clarify the present invention, parts which are
not described in the specification are omitted, and parts for which same
descriptions are provided have the same reference numerals. FIG. 1 shows a block diagram of a presence-based telephony system according to an exemplary embodiment of the present invention.
As shown, the presence-based telephony system includes base
stations (BSs) 10 and 1 1 , mobile switching centers (MSCs) 20, 21 , and 22, a
home location register (HLR) 30, a presence server 40, and a VoIP gateway 50.
The base stations 10 and 1 1 provide a mobile communication
service to mobile stations (MSs) M1 and M2, and include base transceiver
stations (BTSs) 10-1 and 10-2 for interface between the mobile stations M1
and M2 and a mobile communication network, and a base station controller
(BSC) 10-3 for managing the base transceiver stations 10-1 and 10-2 and managing power of signals, frequencies, and handovers. The mobile switching centers 20, 21 , and 22 manage call
connections for telephone terminals accessed through the base stations 10
and 1 1 or VoIP gateway 50, and establish, cancel, and manage connection
paths. The home location register 30 connected to the mobile switching
centers 20 and 21 stores and manages dialed subscriber information, per-
subscriber additional service information, and location information on a
dialed terminal, and is a database for storing categories of services and ID information on a mobile switching center in a home network. Differing from
the prior art, the home location register 30 distinguishes a first case of using
the VoIP through VoIP terminals V1 and V2 and a second case of using the
VoIP without VoIP terminals V1 and V2, and uses presence information of the subscriber to transmit a location of the mobile switching center and subscriber information to the mobile switching centers 20 and 21 so that a dialed call may be provided to the VoIP terminals V1 and V2 when the VoIP
is in use. In this instance, the home location register 30 uses per-subscriber
presence information stored in the presence server 40 to determine whether
to use the VoIP. The home location register 30 stores an electronic serial number
(ESN), a mobile identification number (MIN), a home mobile switching center
identification (MSC ID), and other subscriber information. In this instance, the
ESN can be an integer type and is used to identify a terminal, the MIN can
be an integer type and includes a telephone number, the home MSC ID can be an integer type and is an ID of a mobile switching center nearest a place
where the subscriber subscribes to a service, and the other subscriber
information can be a composite type and is general information on the HLR
including service categories provided to the subscriber. The presence server 40 manages presence of subscribers including
the subscribers' status (offline, online, seat occupation, and dining states),
addresses, and preferred device information. In detail, the presence server 40 stores a user ID, a mobile station
number, status information, a contact address, an MSC ID, and preferred device information. In detail, the user ID can be a string type and identifies
the user, the mobile station number can be an integer type and is a
telephone number of a mobile station to which the call is forwarded, the status information can be an integer type and indicates status of a VoIP terminal such as online, offline, and busy state, the contact address can be
an integer type and includes an IP address and a port number for accessing the VoIP terminal, the MSC ID can be an integer type and is an ID of an
MSC to which the VoIP terminal is accessed, and the preferred device
information can be an integer type and represents a device for receiving a
call, including a VoIP terminal and a mobile station. A dialed call or a dialing
call is connected to the VoIP terminals V1 and V2 when the VoIP terminals
V1 and V2 are registered in preferred device information, and the same is connected to the mobile stations M1 and M2 when the mobile stations M1 and M2 are registered in preferred device information.
When receiving a preferred information inquiry on the mobile
stations M1 and M2 from the HLR 30, the presence server 40 transmits
preferred device information on the telephone numbers of the mobile stations M1 and M2 to the HLR 30, and concurrently transmits thereto an ID
of the MSC to which the corresponding VoIP terminals V1 and V2 are
accessed, and IP addresses and port numbers for accessing the VoIP
terminals V1 and V2 when the VoIP terminals V1 and V2 are established to
be a preferred device. The VoIP gateway 50 allows the VoIP terminals V1 and V2 having
accessed the Internet to transmit or receive a call on the Internet in
cooperation with the Public Land Mobile Network/Public Switched Telephone
Network (PLMN/PSTN). The VoIP terminals V1 and V2 include a softphone and an IP phone which are realized by a device or a program for transmitting
or receiving calls through the VoIP gateway 50 on the Internet. The softphone includes an Internet phone realized as a software program in a PC, a PDA, and a mobile station, and the IP phone represents an Internet phone dedicated device having a program function of the softphone and a
hardwired telephone structure. When using the VoIP terminals V1 and V2 to
log on, the user can input a telephone number to be mapped and receive a
call dialed to the corresponding number through the VoIP terminals V1 and V2. In this instance, the input telephone number is transmitted to the
presence server 40 to be stored therein.
A call routing method in a presence based telephony system
according to an exemplary embodiment of the present invention will now be
described with reference to drawings. FIG. 2 shows a process for connecting a dialing call generated by a
mobile station M1 to a VoIP terminal V1 in a presence-based telephony
system according to an exemplary embodiment of the present invention.
Referring to FIG. 2, when a subscriber of a mobile station M2 uses a
VoIP terminal V1 , the VoIP terminal V1 is automatically or manually established as a preferred device for the telephone number of the mobile
station M2 to the presence server 40, shown by © . The method for
establishing the preferred device will be described later. When a mobile station M1 telephones the mobile station M2, a call is established between an MSC 20 to which the mobile station M1 currently
belongs and the mobile station M1 through the base transceiver station 10-1
and the BSC 10-3, shown by ©.
When the MSC 20 requests a location of an MSC to which the mobile station M2 currently belongs from the HLR 30 so as to know the location of the mobile station M2, the HLR 30 receives preferred device
information on the telephone number of the dialing mobile station M1 ,
information on the MSC 21 to which the VoIP terminal V1 is accessed, and
an IP address and a port number for accessing the VoIP terminal V1 from
the presence server 40, and transmits the same to the MSC 20, shown by Θ. The MSC 20 uses information on the MSC 21 and the VoIP terminal
V1 provided by the HLR 30, and connects a dialed call to the VoIP terminal
V1 through the MSC 21 and the VoIP gateway 50 to thereby connect the dialed call provided by the mobile station M1 to the VoIP terminal V1
currently used by the subscriber and allow a telephonic communication
between the mobile station M1 and the VoIP terminal V1 , shown by © .
Therefore, the subscriber can receive the call generated to the subscriber's
wired/wireless telephone number by using the VoIP terminal V1. FIG. 3 shows a process for connecting a dialing call generated by a
VoIP terminal V1 to a mobile station M1 in a presence-based telephony
system according to an exemplary embodiment of the present invention. It is assumed before describing the exemplary embodiment with
reference to FIG. 3 that the mobile station M1 is established as preferred
device information for the telephone number of the mobile station M1 in the
presence server 40, and it is also desirable in this case to establish a
preferred device of the telephone number of a mobile station to be the corresponding mobile station.
When a user of the VoIP terminal V1 telephones the mobile station M1 under the above-described assumption, the VoIP terminal V1 receives
preferred device information on the telephone number of the dialed mobile
station M1 from the presence server 40, and checks whether the preferred
device for the telephone number of the dialed mobile station M1 corresponds
to the mobile station M1 , shown by ©'. The VoIP terminal V1 establishes a call to the MSC 21 to which the
VoIP terminal V1 currently belongs through the VoIP gateway 50 so as to be
connected to the mobile station M1 , shown by ©'.
When the MSC 21 requests a location of an MSC to which the
mobile station M1 currently belongs from the HLR 30 so as to know the
location of the mobile station M1 , the HLR 30 provides information on the
MSC 20 to which the mobile station M1 belongs to the MSC 21 , shown by
© '. In this instance, the HLR 30 does not refer to preferred device
information through the presence server 40 since the VoIP terminal has
already referred to the preferred device information through the presence
server 40 when the VoIP terminal generates a dialing call for requesting location information of the MSC, and it is also possible for the purpose of
easy design of the HLR 30 that the HLR 30 receives preferred device
information corresponding to a telephone number through the presence
server 40 in all cases and uses the same when location information of the MSC is requested.
The MSC 21 uses information on the MSC 20 provided by the HLR 30 to connect a dialed call to the mobile station M1 through the MSC 20, the BSC 10-3, and the base transceiver station 10-1 , and thereby connect the
dialed call provided by the VoIP terminal V1 to the mobile station M1 used by
the subscriber and allow a telephonic communication between the VoIP
terminal V1 and the mobile station M1 , shown by © '. Therefore, the
subscriber can telephone the mobile station M1 by using the VoIP terminal
V1 based on the presence.
FIG. 4 shows a process for connecting a dialing call generated by a mobile station M1 to another mobile station M2 in a presence-based
telephony system according to an exemplary embodiment of the present
invention. Referring to FIG. 4, when a subscriber of the mobile station M2 uses
a VoIP terminal V1 to establish the VoIP terminal V1 as a preferred device to
the presence server 40 and the subscriber then stops usage of the VoIP
terminal V1 and attempts to use the mobile station M2 again, the user automatically or manually establishes the mobile station M2 as a preferred
device for the telephone number of the mobile station M2 to the presence
server 40, shown by ©".
When the mobile station M1 telephones the mobile station M2, a call is established between the mobile station M1 and the MSC 20 to which the mobile station M1 belongs through the base transceiver station 10-1 and the
BSC 10-3, shown by ©".
When the MSC 20 requests a location of an MSC to which the mobile station M2 currently belongs from the HLR 30 so as to know the location of the mobile station M2, the HLR 30 receives preferred device
information for the telephone number of the dialing mobile station M2
through the presence server 40, and provides information on the MSC 22 to
which the mobile station M2 belongs to the MSC 20 since the mobile station
M2 is established as a preferred device, shown by ©". The MSC 20 uses information on the MSC 22 provided by the HLR
30 to connect a dialed call to the mobile station M2 through the MSC 22 and
the BS 1 1 and thereby connect the dialed call provided by the mobile station
M1 to the mobile station M2 in use and allow a telephonic communication
between the mobile station M1 and the mobile station M2, shown by 0".
Therefore, the subscriber receives the presence-based call by using the
mobile station M2. FIG. 5 shows a process for connecting a dialing call generated by a
VoIP terminal V1 to another VoIP terminal V2 in a presence-based telephony
system according to an exemplary embodiment of the present invention. Referring to FIG. 5, when the subscriber of the mobile station M1
uses a VoIP terminal V2, the subscriber automatically or manually
establishes the VoIP terminal V2 as a preferred device for the telephone
number of the mobile station M1 to the presence server 40, shown by ©'".
When the user of the VoIP terminal V1 telephones the mobile station M1 , the VoIP terminal V1 receives preferred device information on the telephone number of the dialed mobile station M1 through the presence server 40, and checks whether the preferred device for the telephone number of the dialed mobile station M1 corresponds to the VoIP terminal V2,
shown by ©'".
The VoIP terminal V1 is connected to the VoIP terminal V2 through
the VoIP gateway 50 in the VoIP system to perform a telephonic
communication, shown by ©'". In this instance, the dialing or dialed process
is performed through the wired/wireless telephone number based on the presence in the VoIP system without connection to the PLMN/PSTN since
users of the mobile stations M1 and M2 use the VoIP terminals V1 and V2. The process for transmitting or receiving a call by using the mobile
stations M1 and M2 or the VoIP terminals V1 and V2 in the presence-based
telephony system according to the exemplary embodiment of the present
invention has been described with reference to FIGs. 2 to 5. Call routing is performed when the HLR 30 provides subscriber information, and the routing
is exceptionally performed in the VoIP system without the HLR 30 when a
dialing call provided by the VoIP terminals V1 and V2 is routed to the VoIP terminals V1 and V2. The HLR 30 determines whether to request relevant
information, that is, preferred device information from the presence server 40, and route a call to the subscriber's mobile stations M1 and M2 or to route the
call to the VoIP terminals V1 and V2, when providing subscriber information
in the above-noted routing process. Realization of the routing process requires the following four
processes. The first process is for a subscriber of mobile stations M1 and M2 to register VoIP terminals V1 and V2 to the presence server 40 when the
subscriber logs in to the presence server 40 from the VoIP terminals V1 and
V2 so as to use the VoIP terminals V1 and V2. The mobile stations M1 and
M2 and the VoIP terminals V1 and V2 were in use since the mobile stations M1 and M2 were established as the preferred device corresponding to the
telephone number of the mobile stations M1 and M2, but the call routing is
now performed on the mobile stations M1 and M2 because of establishment
of the preferred device.
The second process is to establish the VoIP terminals V1 and V2 as
a preferred device, that is, to determine to which device the subscriber of
mobile stations M1 and M2 routes the call. In this instance, the call provided to the telephone number of the mobile stations M1 and M2 is forwarded to
the corresponding VoIP terminals V1 and V2 when the VoIP terminals V1
and V2 are established as a preferred device.
The third process is to forward the call. In detail, The MSC on the side of a dialing person receives a call request from the dialing person, and
requests information for detecting a dialed person's location from the HLR
30, and the HLR 30 provides information according to the preferred device
established to the presence server 40 so that the call may be forwarded to
the terminal established to be a preferred device. The last process is to perform unregistration to route the call to the mobile stations M1 and M2 when the usage of VoIP terminals V1 and V2 is terminated. The above-described four processes will now be described with reference to drawings.
FIG. 6 shows a process for registering and updating presence in a
presence-based telephony system according to an exemplary embodiment
of the present invention. In detail, FIG. 6 shows that a user logs in to the
presence server 40 through the VoIP terminals V1 and V2 to register the
user's status and establish a preferred device.
The process of register() is to transmit information on the VoIP
terminals V1 and V2 such as an ID, a telephone number, a password, and a contact address to the presence server 40 to register presence information,
and thereby the VoIP terminals V1 and V2 becomes online. In this instance,
the online state represents a state in which the VoIP terminals V1 and V2 can receive a call, but the call is actually transmitted to the mobile stations
M1 and M2 since the VoIP terminals V1 and V2 have a low preference when
the mobile stations M1 and M2 are online.
The process of setPreferredDevice() for establishing a preferred device is to transmit a signal for indicating that the most preferred device
through which the subscriber desires to receive a call is the VoIP terminals
V1 and V2 to the presence server 40 to thus update preferred device
information. When this process is finished, the VoIP terminals V1 and V2 have the highest preference, and the call is transmitted not to the mobile stations M1 and M2 of the dialed person but to the VoIP terminals V1 and V2.
FIG. 7 shows a process for forwarding a call according to presence in a presence-based telephony system according to an exemplary embodiment of the present invention. In detail, FIG. 7 shows a process for
forwarding a call based on the presence among the HLR 30, the presence
server 40, and the MSCs 20, 21 , and 22.
The process of getLocation() for requesting a location of a dialed
person is for the MSCs 20, 21 , and 22 of a dialing person to request the
location of the dialed person from the HLR 30. The process of fetch Presence() for receiving device information to
which the call will be forwarded is for the HLR 30 to request preferred device
information and other information relevant to the preferred device information
(e.g., information on the MSC to which corresponding VoIP terminals V1 and
V2 are connected, and an IP address and a port number for accessing the
VoIP terminals V1 and V2 when the VoIP terminals V1 and V2 are established as a preferred device) from the presence server 40 and receive
the same therefrom. The process of passCall() for forwarding the call is for the MSC
having received location information on the dialed person from the HLR 30 to forward the call to the preferred device of the dialed person.
FIG. 8 shows a process for unregistering presence in a presence- based telephony system according to an exemplary embodiment of the
present invention.
Referring to FIG. 8, when the user transmits an unregister() request indicating unregistration to the presence server 40 from the VoIP terminals
V1 and V2 so as to terminate the usage of VoIP terminals V1 and V2, the
call is forwarded to the mobile stations M1 and M2 in a like manner described with reference to FIG. 7 since the mobile stations M1 and M2 become the preferred device when the HLR 30 requests a fetch Presence()
from the presence server 40.
Various methods for modifying the subscriber's presence will be
described which include a method for automatically modifying the presence based on the establishment and other factors of a method for manually
modifying the same through the subscriber's manipulation.
The method for automatically modifying the presence will now be
described. The first method is to automatically change the presence when a VoIP terminal is logged on. The presence is automatically changed so that
the user may use the VoIP terminal when the user using the mobile stations
M1 and M2 or a cable telephone logs in to the VoIP terminal.
In detail, when the user using the existing wired/wireless telephone drives a VoIP terminal, the user receives a right to use a VoIP terminal
through a certification process. When the certification is successful, the
presence server 40 automatically modifies the presence so that call routing
may be available to the VoIP terminal, and the user can then
receive/transmit a call by using the corresponding VoIP terminal. The second method is to automatically change the presence when
the user generates no reaction for a predetermined time, established by the
user. The presence is automatically switched to a wired/wireless telephone to which the corresponding VoIP terminal is subscribed when the user generates no reaction caused by manipulation of the VoIP terminal for a specific initial time or a predetermined time (e.g., reaction caused through a mouse and a keyboard of a computer, and peripherals).
In detail, when the user activates establishment of the automatic
presence switching function of the VoIP terminal and inputs an automatic
switching time, the VoIP terminal requests a change of presence from the presence server 40 when no reaction caused by manipulation of the VoIP terminal is provided for a specific initial time or an automatic switching time
input by the user. Therefore, the presence server 40 checks that the VoIP
terminal having requested the change of presence is certified, and automatically switches the presence of the corresponding user to the
wired/wireless telephone so that the user may receive the call through the
corresponding wired/wireless telephone.
The third method is to automatically switch the presence by using a
position tracking system for tracking the position of a mobile station through a base station. The presence is automatically changed by utilizing the
position tracking system so that the mobile station may be dialed when the mobile station leaves an area where the VoIP terminal is available.
In detail, when the user who was using a VoIP terminal carries a
mobile station with him and moves to another region from the VoIP terminal
available area without additional establishment, the base station senses the
movement of the mobile station by the user, the MSC requests a change of presence of the corresponding user upon registering location information of
the corresponding mobile station to the HLR 30, and the HLR 30 communicates with the presence server 40 to modify the corresponding user's presence and thereby allow the user to receive a call through a
corresponding subscribed wired/wireless telephone.
The methods for manually modifying the presence will now be
described.
The first method is for the user to manually switch the presence
while using a VoIP terminal. That is, the user can modify the user's presence
information in the VoIP terminal status, and thereby the user manually
switches the presence.
In detail, when the user activates the function of 'receiving a call
through a wired/wireless telephone' while using a VoIP terminal, the VoIP
terminal requests a change of presence from the presence server 40 so that
the call routing may be available through the wired/wireless telephone, and hence, the user can receive a call by using the subscribed wired/wireless
telephone.
The second method is to manually switch the presence by utilizing
the automatic response system (ARS). An ARS for establishing the user's
presence is provided to the user, and the user accesses the ARS through a
wired/wireless telephone to select a menu number, thereby switching the presence.
In detail , the user desiring to modify the presence uses a
wired/wireless telephone to access an allocated ARS number, and selects a menu for modifying the presence according to the ARS guide. When the user finishes the desired selection, the MSC requests a change of presence
from the HLR 30 according to the corresponding establishment, and the HLR 30 checks the presence through a communication with the presence server
40, and modifies the presence when a condition is satisfied, so that the call
routing may be available with the subscribed wired/wireless telephone.
Hence, the user can receive a call with the corresponding subscribed
wired/wireless telephone.
The third method is to manually switch the presence by utilizing a
virtual machine (VM) application of a mobile station. The presence is modified by driving the VM application downloaded into the mobile station.
In detail, the mobile station user downloads a VM application for
presence modification to the mobile station according to a predetermined
receiving method, and drives the VM application. When the user performs a
desired establishment, the presence server 40 checks the established
presence, and modifies the presence when the established presence
satisfies a condition so that the call routing may be available with the subscribed wired/wireless telephone. Hence, the user can receive a call with
the corresponding subscribed wired/wireless telephone. The fourth method is to manually switch the presence by utilizing the wireless Internet. The user accesses the wireless Internet for establishing the
presence of the user, and modifies the presence.
In detail, the user accesses the wireless Internet through a mobile
station, and selects a menu for modifying the presence. When the user
performs a desired establishment, the presence server 40 checks the established presence, and modifies the presence when the established presence satisfies a condition so that the call routing may be available with the subscribed wired/wireless telephone. Hence, the user can receive a call with the corresponding subscribed wired/wireless telephone.
The fifth method is to manually switch the presence by short
message service (SMS) transmission. The presence is modified by
transmitting an SMS message to a specific service telephone number through the mobile station. In this instance, it is desirable to modify the
presence irrespective of message contents. In detail, the user uses a mobile station to transmit an SMS
message to which the user's current state is written to an allocated number
to the system, the system receives the SMS message, requests a change of presence from the MSC, the MSC requests a change of presence according to a corresponding establishment from the HLR 30, and the HLR 30 checks
the presence through a communication with the presence server 40 and
modifies the presence when the established presence satisfies a condition
so that the call routing may be available with the subscribed wired/wireless telephone. Hence, the user can receive a call with the corresponding
subscribed wired/wireless telephone. The sixth method is to manually switch the presence through a
dedicated IP phone. The presence is modified when the user selects a drive
of a 'call routing' function of the IP phone for establishing the presence.
In detail, when the user establishes a 'call routing' function on the
dedicated IP phone, the IP phone requests a change of presence from the presence server 40 so that the call routing may be available with the
subscribed wired/wireless telephone. Hence, the user can receive a call with the subscribed wired/wireless telephone. The seventh method is to manually switch the presence by utilizing a
dedicated mobile station having a call routing function therein.
In detail, when the user uses a mobile station with a built-in call routing function to establish presence, the MSC requests a change of
presence according to the corresponding establishment from the HLR 30,
and the HLR 30 checks the presence through a communication with the
presence server 40 and modifies the presence when the established presence satisfies a condition so that the call routing may be available with
the subscribed wired/wireless telephone. Hence, the user can receive a call
with the desired device. The eighth method is to manually switch the presence through the
web. In detail, when the user accesses a website which provides a presence modification function to finish a certification process and
determines a receiving method through the presence modification, the web
system requests corresponding establishment from the MSC, the MSC
requests a change of presence according to the corresponding establishment from the HLR 30, and the HLR 30 checks the presence through a communication with the presence server 40 and modifies the
presence when the established presence satisfies a condition so that the call
routing may be available with the subscribed wired/wireless telephone.
Hence, the user can receive a call with the subscribed wired/wireless telephone. The above-noted methods are described on the wireless network basis, and are also applicable to cable networks, cable intelligent networks,
and next generation networks (NGNs). FIG. 9 shows a block diagram of a presence-based cable intelligent
network system according to an exemplary embodiment of the present
invention. As shown, the presence-based cable intelligent network system
based on the standard communication rule of Common Channel Signaling
System No. 7 (SS7 protocol) defined by ITU-T includes service switching
points (SSPs) 120, 121 , and 122, signal transfer points (STPs) 140, 141 , 142, and 143, a service control point (SCP) 150, a presence server 160, and a
VoIP gateway 170. The SSPs 120 and 121 provide an intelligent network service to
wired terminals 1 10 and 1 12 accessed through transmission of signal
messages with each other. In this instance, the SSP 120 can be accessed to
a wired terminal 1 1 1 through a private branch exchange (PBX) 130. The STPs 140, 141 , 142, and 143 transmit signals of thg SS7 protocol to the wired terminals accessed through the SSPs 120 and 121 or
the VoIP gateway 170 accessed to the SSP 122.
The SCP 150 accessed to the STP 142 stores and manages
information on dialed subscribers, per-subscriber additional services, and locations of dialed terminals. The SCP 150 has the same function as that of the HLR 30 for a presence-based call connection described with reference to FIGs. 1 to 8. That is, information for identifying a case of using the VoIP through a VoIP terminal and a case of not using the VoIP based on the
subscriber's presence information including the location of the SSP
managing the subscriber and subscriber information is transmitted to the
SSP 120 and 121 so that a dialed signal may be connected to the VoIP
terminal 180 when the VoIP is in use. In this instance, the SCP 150 uses the per-subscriber presence information stored in the presence server 160 to
determine whether to use the VoIP. The presence server 160 and the VoIP gateway 170 will not be
described since they almost correspond to those of FIGs. 1 to 8 described on
the wireless network basis. No call routing method in the above-structured and functioned
presence-based cable intelligent network system will be described since the
configuration and operation of the SSPs 120, 121 , and 122, the SCP 150,
the presence server 160, and the VoIP gateway 170 are similar to those of
the HLR 30, the MSC 20, 21 , and 22, the presence server 40, and the VoIP
gateway 50 shown in FIGs. 1 to 8, and they will be easily understood by a
person skilled in the art. While this invention has been described in connection with what is
presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed
embodiments, but, on the contrary, is intended to cover various modifications
and equivalent arrangements included within the spirit and scope of the appended claims.
For example, it has been described in the above that the user can use a VoIP terminal to receive a call provided to a telephone number of the
user's mobile station by modifying the presence between the mobile station
and the VoIP terminal, that is, by modifying the preferred device information, and without being restricted to this, it will also be easily understood by a person skilled in the art by referring to the above descriptions that a user of a wired telephone can use the VoIP terminal to receive a call provided to the user's wired telephone number by modifying the presence between the wired
telephone and the VoIP terminal, that is, by modifying the preferred device information. Therefore, the user can receive calls generated to the user's existing wired/wireless telephone number by using a VoIP terminal connected to the Internet without spatial restrictions. Also, the user can use wired/wireless telephone services without an additional communication device if the user has a VoIP terminal connected to the Internet when subscribing to a wired telephone service or a mobile telephone service. Further, the user can pay a lesser network access fee to communication service providers compared to the case of transmitting a call through the existing cable network or mobile communication network since the call received by the user is transmitted through the Internet, and hence, the user's calling fee is reduced.