阅读说明：本技术 用于将pbx分机与云服务应用的用户账户相关联的方法 (method for associating a PBX extension with a user account of a cloud service application ) 是由 奥列弗·克雷特 穆萨·扎格杜德 齐里尔·马扎尔 于 2018-03-26 设计创作，主要内容包括：一种用于将PBX分机(21)与用户帐户(31)相关联的方法,该方法包括：(S1)从用户帐户(31)接收包括PBX分机电话号码的关联请求,(S2)将关联代码发送至用户帐户(31),(S6)向PBX中央单元(22)发送将PBX分机(21)连接至IVR应用(33)的命令,(S8)通过IVR应用(33)从PBX分机(21)接收关联代码,(S10)如果从PBX分机(21)接收到的关联代码与发送至用户帐户(31)的关联代码相同,则使得能够通过CTI链路(51)从用户帐户(31)控制PBX分机(21)。(a method for associating a PBX extension (21) with a user account (31), the method comprising: (S1) receiving an association request comprising a PBX extension telephone number from the user account (31), (S2) sending an association code to the user account (31), (S6) sending a command to the PBX central unit (22) to connect the PBX extension (21) to the IVR application (33), (S8) receiving an association code from the PBX extension (21) through the IVR application (33), (S10) enabling control of the PBX extension (21) from the user account (31) over the CTI link (51) if the association code received from the PBX extension (21) is the same as the association code sent to the user account (31).)

1. A method for associating a PBX extension (21) with a user account (31) of a cloud service application for controlling the PBX extension,

The cloud service application for controlling the PBX extension is provided by a cloud infrastructure (30), the cloud infrastructure (30) comprising at least a cloud service server (32),

the PBX extension (21) belonging to a PBX system (20), the PBX system (20) further comprising a PBX central unit (22) connecting the PBX extension (21) to a public switched telephone network (40),

The PBX central unit (22) and the cloud service server (32) are connected via a Computer Telephony Integration (CTI) link (51) over an Internet protocol network (50),

the cloud infrastructure (30) also providing an interactive voice response, IVR, application available to the PBX extension (21) over the PSTN network (40),

The method comprises the following steps:

(S1) receiving, at the cloud service server (32), an association request from a user account (31), the association request including a PBX extension telephone number,

(S2) sending an association code from the cloud service server (32) to the user account (31),

(S4) sending a command from the cloud service server (32) to the PBX central unit (22) to monitor the PBX extension (21) associated with the PBX extension telephone number,

(S6) sending a command from the cloud service server (32) to the PBX central unit (22) to connect the PBX extension (21) associated with the PBX extension telephone number to the IVR application (33), the command including a public extension telephone number directed to the IVR application (33),

(S8) receiving an association code at the cloud service server (32) from the PBX extension (21) through the IVR application (33),

(S9) comparing, at the cloud service server (32), the association code received by the IVR application (33) with the association code sent to the user account (31),

(S10) associating, at the cloud service server (32), the PBX extension (21) with the user account (31) if the association code received from the PBX extension (21) is the same as the association code sent to the user account (31), thereby enabling control of the PBX extension (21) from the user account (31) over the CTI link (51).

2. The method of claim 1, wherein sending (S4) a command from the cloud service server (32) to the PBX central unit (22) to monitor the PBX extension (21) associated with the PBX extension telephone number is performed (S3) upon receiving (S3) an association complete request from the user account (31).

3. The method of claim 1 or 2, further comprising:

(S5) sending a command to the PBX central unit (22) over the CTI link (51) to lock the PBX extension (21) associated with the PBX extension telephone number, wherein a local PBX extension code is to be dialed at the PBX extension (21) to unlock the PBX extension (21), the local PBX extension code being different from the associated code.

4. the method of claim 1 or 2, further comprising: (S21) generating, at the cloud service server (32), an association context identifier associated with the association code and storing the association code with the association context identifier,

Wherein the command to connect the PBX extension (21) associated with the PBX extension telephone number to the IVR application (33) further comprises the association context identifier,

and wherein the method further comprises: (S31) receiving, at the cloud service server (32), the association context identifier from the PBX central unit (22) through the IVR application (33),

And wherein (S9) comparing the association code received from the PBX extension (21) with the association code sent to the user account (31) comprises: retrieving an association code sent to the user account (31) based on the association context identifier received by the IVR application (33).

5. The method of claim 3, further comprising: (S21) generating an association context identifier associated with the association code at the cloud service server (32) and storing the association code with the association context identifier,

wherein the command to connect the PBX extension (21) associated with the PBX extension telephone number to the IVR application (33) further comprises the association context identifier,

and wherein the method further comprises: (S31) receiving, at the cloud service server (32), the association context identifier from the PBX central unit (22) through the IVR application (33),

and wherein (S9) comparing the association code received from the PBX extension (21) with the association code sent to the user account (31) comprises: retrieving an association code sent to the user account (31) based on the association context identifier received by the IVR application (33).

6. The method of claim 4, further comprising: detecting, by the IVR application (33), a direct internal dialing number for calling a PBX extension (21), and associating, at the cloud service server (32), the detected direct internal dialing number for the PBX extension (21) with the user account.

7. The method of claim 5, further comprising: detecting, by the IVR application (33), a direct internal dialing number for calling a PBX extension (21), and associating, at the cloud service server (32), the detected direct internal dialing number for the PBX extension (21) with the user account

8. The method of claim 3, further comprising: detecting, by the IVR application (33), a direct internal dialing number for calling a PBX extension (21), and associating, at the cloud service server (32), the detected direct internal dialing number for the PBX extension (21) with the user account.

9. The method of claim 2, further comprising: detecting, by the IVR application (33), a direct internal dialing number for calling a PBX extension (21), and associating, at the cloud service server (32), the detected direct internal dialing number for the PBX extension (21) with the user account.

10. A cloud architecture (30) providing a cloud services application for controlling PBX extensions belonging to a PBX system (20), the PBX system (20) further comprising a PBX central unit (22) connecting a PBX extension (21) to a public switched telephone network (40),

the cloud infrastructure (30) comprises at least a cloud service server (32),

The cloud infrastructure (30) providing IVR applications (33) available to the PBX extension (21) over the PSTN network (40),

the cloud service server (32) comprises:

A CTI link (51) for communicating with the PBX central unit (22) over an Internet protocol network (50),

A control device arranged to:

(S1) receiving, at the cloud service server (32), an association request from a user account (31), the association request including a PBX extension telephone number,

(S2) sending an association code from the cloud service server (32) to the user account (31),

(S4) sending a command from the cloud service server (32) to the PBX central unit (22) to monitor the PBX extension (21) associated with the PBX extension telephone number, (S6) sending a command from the cloud service server (32) to the PBX central unit (22) to connect the PBX extension (21) associated with the PBX extension telephone number to the IVR application (33), the command comprising a public extension telephone number directed to the IVR application (33),

(S8) receiving an association code at the cloud service server (32) from the PBX extension (21) through the IVR application (33),

(S9) comparing, at the cloud service server (32), the association code received by the IVR application (33) with the association code sent to the user account (31),

(S10) associating, at the cloud service server (32), the PBX extension (21) with the user account (31) if the association code received from the PBX extension (21) is the same as the association code sent to the user account (31), thereby enabling control of the PBX extension (21) from the user account (31) over the CTI link (51).

11. a method for associating a PBX extension (21) with a user account (31) of a cloud service application for controlling the PBX extension,

The cloud service application for controlling the PBX extension is provided by a cloud infrastructure (30), the cloud infrastructure (30) comprising at least a cloud service server (32),

The PBX extension (21) belonging to a PBX system (20), the PBX system (20) further comprising a PBX central unit (22) connecting the PBX extension (21) to a public switched telephone network (40),

the PBX central unit (22) and the cloud service server (32) are connected via a CTI link (51) over an Internet protocol network (50),

The cloud infrastructure (30) also provides IVR applications available to the PBX extension (21) over the PSTN network (40),

The method comprises the following steps:

(S11) monitoring, at the PBX central unit (22), the PBX extension (21) associated with the PBX extension telephone number included in the command, after receiving, from the cloud service server (32), at the PBX central unit (22), a command to monitor a PBX extension (21), the command including the PBX extension telephone number of the PBX extension (21) to be monitored,

(S14) upon receiving, at the PBX central unit (22), a command from the cloud service server (32) to connect the PBX extension (21) associated with the PBX extension telephone number with the IVR application (33), the command including a common extension telephone number directed to the IVR application (33), connecting (S15, S16) the PBX extension (21) associated with the PBX extension telephone number with the common extension telephone number directed to the IVR application (33),

(S27) sending an association code dialed by the user at the PBX extension (21) from the PBX extension (21) to the public extension telephone number directed to the IVR application (33).

12. the method of claim 11, further comprising:

(S22) locking the PBX extension (21) after receiving a command at the PBX extension (21) from the PBX central unit (22) to lock the PBX extension (21),

(S25) unlocking the PBX extension (21) if a valid local PBX extension code is dialed at the PBX extension (21), the local PBX extension code being different from the association code.

13. the method of claim 11 or 12, further comprising: encoding an association code dialed at the PBX extension (21) within a dual tone multi frequency signaling DTMF signal.

14. A PBX system (20) comprising:

PBX extensions (21), each PBX extension (21) comprising a user interface arranged for dialing an association code,

A PBX central unit (22) comprising

Control means arranged for connecting the PBX extension (21) to a public switched telephone network (40),

a CTI link (51) for communicating with a cloud service server (32) over an Internet protocol network (50), the cloud service server (32) belonging to a cloud infrastructure (30) also providing IVR applications available to the PBX extension (21) over the PSTN network (40),

The control device (S11) is arranged for:

(S11) monitoring the PBX extension (21) associated with the PBX extension telephone number included in the command after receiving the command to monitor the PBX extension (21) from the cloud service server (32), the command including the PBX extension telephone number of the PBX extension (21) to be monitored,

(S14) upon receiving from the cloud service server (32) a command to connect the PBX extension (21) associated with the PBX extension telephone number with an IVR application (33), the command including a public extension telephone number directed to the IVR application (33), connecting (S15, S16) the PBX extension (21) associated with the PBX extension telephone number with a public extension telephone number directed to the IVR application (33),

Each PBX extension (21) further comprises control means arranged for:

(S27) sending the association code dialed at the PBX extension (21) to the public extension telephone number directed to the IVR application (33).

15. A communication system comprising the cloud architecture (30) of claim 10 and the PBX system (20) of claim 14.

Technical Field

The invention relates to a cloud service application for controlling a PBX extension. A PBX (private branch exchange) is a system that connects telephone extensions to the public switched telephone network and provides internal communications.

background

In the context of a hybrid cloud solution that couples communication devices of a PBX system (also known as PBX phones or extensions) deployed on a customer premises and a cloud service that enables PBX users to drive their phones from rich cloud applications through CTI, there is a need for an easy-to-use and secure way to associate users of such cloud services with PBX extensions of users who will enable the services.

Disclosure of Invention

The invention provides a method for associating a PBX extension with a user account of a cloud service application for controlling the PBX extension, the cloud service application for controlling the PBX extension being provided by a cloud infrastructure, the cloud infrastructure comprising at least a cloud service server, the PBX extension belonging to a PBX system, the PBX system further comprising a PBX central unit connecting the PBX extension to a public switched telephone network, the PBX central unit and the cloud service server being connected via a computer telephony integrated CTI link over an internet protocol network, the cloud infrastructure further providing an interactive voice response, IVR, application available to the PBX extension over a PSTN network, the method comprising: receiving, at a cloud service server, an association request from a user account, the association request including a PBX extension telephone number; sending an association code from the cloud service server to the user account; sending, from the cloud service server to the PBX central unit, a command to monitor a PBX extension associated with the PBX extension telephone number; sending, from the cloud service server to the PBX central unit, a command to connect a PBX extension associated with the PBX extension telephone number to the IVR application, the command including a common extension telephone number directed to the IVR application; receiving, at the cloud service server, an association code from the PBX extension through the IVR application; comparing, at the cloud service server, the association code received through the IVR application with the association code sent to the user account; associating the PBX extension with the user account at the cloud service server if the association code received from the PBX extension is the same as the association code sent to the user account, thereby enabling control of the PBX extension from the user account over the CTI link.

In an embodiment, the method further comprises detecting, by the IVR application, a direct internal dialing number for calling the PBX extension, and associating, at the cloud service server, the detected direct internal dialing number for the PBX extension with the user account.

transmitting the activation code to the cloud service user account (end user) ensures that the correct person receives the information. Verifying the code by directing the CTI connection of the associated PBX extension ensures that the operation is done on the correct PBX extension and by the correct person.

The user-equipment association method provided by the invention is easy to execute and hardly requires human interaction, thereby reducing the operation cost to the minimum. The method ensures that the association is done on the correct phone, avoids configuration errors and identity tampering (fraudulent use of the device), and provides a way for cloud service providers to track and prevent fraud.

the present invention enables end users to perform such associations themselves by an easy-to-apply method, while providing assurance to cloud service providers and enterprise administrators that the operation will not result in an undetectable invalid association.

The user-device association method according to the present invention does not require a company administrator action nor a cloud administrator action, and therefore, for the association action, no operation cost is generated for each user. Thus, user registration is easily achieved, and such a solution would facilitate administrators to employ cloud services.

the user-device association method according to the present invention does not disclose company sensitive information such as PBX/phone password to the cloud service.

the user-device association method according to the invention is applicable to all PBXs providing CTI links.

in an embodiment, sending a command from the cloud service server to the PBX central unit to monitor PBX extensions associated with the PBX extension telephone numbers is performed after receiving an association complete request from the user account.

in an embodiment, the method further comprises: sending a command to the PBX central unit over the CTI link to lock a PBX extension associated with the PBX extension telephone number, wherein a local PBX extension code is to be dialed at the PBX extension to unlock the PBX extension, the local PBX extension code being different from the associated code.

In an embodiment, the method further comprises: generating, at the cloud service server, an association context identifier associated with the association code and storing the association code with the association context identifier, wherein the command to connect the PBX extension associated with the PBX extension telephone number to the IVR application further includes the association context identifier, and wherein the method further comprises: receiving, at the cloud service server, an association context identifier from the PBX central unit through the IVR application, and wherein comparing the association code received from the PBX extension to the association code sent to the user account comprises: an association code sent to the user account is retrieved based on the association context identifier received through the IVR application.

In an embodiment, the method further comprises: detecting, by the IVR application, a direct internal dialing number for calling the PBX extension, and associating, at the cloud service server, the detected direct internal dialing number for the PBX extension with the user account.

In an embodiment, the association code received by the IVR application is encoded within a dual tone multi frequency signaling DTMF signal.

The present invention also provides a cloud architecture providing a cloud service application for controlling PBX extensions belonging to a PBX system, the PBX system further comprising a PBX central unit connecting the PBX extensions to a public switched telephone network, the cloud infrastructure comprising at least a cloud service server, the cloud infrastructure providing IVR applications available to the PBX extensions over a PSTN network, the cloud service server comprising: a CTI link for communicating with the PBX central unit over an Internet protocol network; a control device arranged to: receiving, at a cloud service server, an association request from a user account, the association request including a PBX extension telephone number; sending an association code from the cloud service server to the user account; sending, from the cloud service server to the PBX central unit, a command to monitor a PBX extension associated with the PBX extension telephone number; sending, from the cloud service server to the PBX central unit, a command to connect a PBX extension associated with the PBX extension telephone number to the IVR application, the command including a public extension telephone number directed to the IVR application; receiving, at the cloud service server, an association code from the PBX extension through the IVR application; comparing, at the cloud service server, the association code received through the IVR application with the association code sent to the user account; associating the PBX extension with the user account at the cloud service server if the association code received from the PBX extension is the same as the association code sent to the user account, thereby enabling control of the PBX extension from the user account over the CTI link.

the invention also provides a method for associating a PBX extension with a user account of a cloud service application for controlling the PBX extension, the cloud service application for controlling the PBX extension being provided by a cloud infrastructure, the cloud infrastructure comprising at least a cloud service server, the PBX extension belonging to a PBX system, the PBX system further comprising a PBX central unit connecting the PBX extension to a public switched telephone network, the PBX central unit and the cloud service server being connected via a CTI link over an internet protocol network, the cloud infrastructure further providing an IVR application available to the PBX extension over a PSTN network, the method comprising: after receiving, at the PBX central unit from the cloud service server, a command to monitor the PBX extensions, the command including the PBX extension telephone number of the PBX extension to be monitored, monitoring, at the PBX central unit, the PBX extension associated with the PBX extension telephone number included in the command; receiving, at the PBX central unit from the cloud service server, a command to connect a PBX extension associated with the PBX extension telephone number with the IVR application, the command including a public extension telephone number directed to the IVR application, and then connecting the PBX extension associated with the PBX extension telephone number with the public extension telephone number directed to the IVR application; an association code dialed by the user at the PBX extension is sent from the PBX extension to a public extension telephone number directed to the IVR application.

In an embodiment, the method further comprises: the method further includes locking the PBX extension upon receiving a command from the PBX central unit at the PBX extension to lock the PBX extension, and unlocking the PBX extension if a valid local PBX extension code is dialed at the PBX extension, the local PBX extension code being different from the association code.

in an embodiment, the method further comprises encoding the association code dialed at the PBX extension within a dual tone multi frequency signaling DTMF signal.

The present invention also provides a PBX system, including: PBX extensions, each PBX extension comprising a user interface arranged for dialing an association code; a PBX central unit comprising control means configured for connecting the PBX extension to a public switched telephone network, a CTI link for communicating with a cloud service server over an internet protocol network, the cloud service server belonging to the cloud infrastructure also providing an IVR application available to the PBX extension over a PSTN network, the control means being arranged for: upon receiving a command from the cloud service server to monitor a PBX extension, the command including a PBX extension telephone number of the PBX extension to be monitored, monitoring the PBX extension associated with the PBX extension telephone number included in the command; upon receiving from the cloud service server a command to connect a PBX extension associated with the PBX extension telephone number with the IVR application, the command including a common extension telephone number directed to the IVR application, connecting the PBX extension associated with the PBX extension telephone number with the common extension telephone number directed to the IVR application, each PBX extension further comprising the following control means: the control means is arranged to send the association code dialled at the PBX extension to a common extension telephone number leading to the IVR application.

The invention also provides a communication system comprising the cloud architecture and the PBX system.

drawings

these and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter by way of example with reference to the accompanying drawings.

Figure 1 is a representation of a hybrid system including a PBX system and a cloud architecture.

Fig. 2 illustrates a user-device association method according to the present invention.

Fig. 3 is a message sequence chart of an embodiment of the method of fig. 2.

Detailed Description

Figure 1 is a representation of a hybrid system including a PBX system 20 and a cloud architecture 30. The PBX system 20 may belong to a company that has subscribed to cloud services, among other things.

The PBX system 20 includes a plurality of PBX extensions 21 and at least one PBX central unit 22. The PBX central unit 22 and the PBX extensions 21 may be located at the same site or at different sites. In particular, if there is more than one PBX central unit 22, the PBX central units 22 may be located at different sites.

The PBX extension 21 may be any type of telephone supported by the PBX (IP, TDM, analog, softphone) as long as it supports CTI monitoring on the telephone. The PBX extension 21 comprises a user interface arranged for dialing the association code. The user interface may be as simple as a basic dial.

The PBX system 20 comprises a PBX central unit 22 arranged for connecting the PBX extensions 21 to the public switched telephone network 40.

Computer Telephony Integration (CTI) link 51 enables collaboration between PBX system 20 and cloud infrastructure 30 over internet protocol network 50.

The cloud infrastructure 30 provides cloud service applications for controlling PBX extensions belonging to the PBX system 20. The cloud infrastructure 30 includes at least one cloud service server 32. The cloud service server 32 may be composed of separate entities that interact together.

The cloud infrastructure 30 also provides an interactive voice response, IVR, application available to the PBX extension 21 over the PSTN network 40. The IVR enables the PBX extension 21 to interact with the user by using voice and DTMF tones entered via the keyboard.

Storage spaces or containers (logical or physical), referred to hereinafter as storage libraries 35, are stored in the cloud architecture 30.

Each end user of the PBX system 20 has a cloud service user account 31 for cloud services.

the repository 35 registers all PBX extensions 21 of the PBX system 20 and all service user accounts 31 associated with the PBX system 20 in a logical space corresponding to the subscribing company.

the PBX extension 21 may be associated with only the cloud service user account 31 if the cloud service user account 31 is registered in the same repository 35 as the PBX extension 21.

The PBX extension 21 or set of PBX extensions 21 of the PBX system 20 is connected to the cloud architecture 30 by a CTI link 51 providing a CTI connection between the cloud service and the PBX central unit 22, enabling CTI-driven actions to be applied to the PBX extensions from the cloud during and after association of the PBX extensions with the end users.

The method for associating a PBX extension 21 with a user account 31 of a cloud service application for controlling the PBX extension comprises the following steps.

using, for example, a desktop or mobile phone to log into the user account 31 of his cloud service application, the end user can start a PBX extension association by entering his PBX extension telephone number known at the PBX level (i.e. this is the end user's internal telephone number in the enterprise PBX system) in the cloud service application. This step may be done by the user manually entering the PBX extension telephone number (which the cloud service then verifies is registered in the repository 35 associated with the user's PBX system), or by selecting from a limited list of extension telephone numbers that the cloud service can build by comparing the user's name, which is known at the cloud account level, with information retrieved from the PBX database (typical directory information retrieved from the PBX and mapping the extension to the person's name).

Upon receiving the association request including the user account 31 identifier and the PBX extension phone number input by the end user at step S1, the cloud service server 32 generates an association code, stores the association code in the memory of the cloud service server 32, and transmits the association code to the user who generated the user account of the association request at step S2. The association code may be, for example, a simple Personal Identification Number (PIN) consisting of 4 digits. The association code may be sent to the cloud service user account 31, in particular by the cloud service application. The association code may also be sent by an out-of-band method. Using an out-of-band approach may reduce the risk of operations by people who have stolen cloud service account credentials, and may also enable cloud service operators to more easily record and audit operations. The out-of-band method may be, for example, based on email or mobile phone, provided that the information (email or mobile phone, respectively) was created and verified at the time of cloud service account creation, and cannot be modified thereafter without verification by the cloud provider.

at step S21, the cloud service server 32 may generate an association context identifier. The association context identifier is stored with the association code generated at step S2.

Once the user receives the association code, he may have to request association completion from his cloud service application user account 31 by sending a completion request to the cloud service server 32 at optional step S3. The next step requires the user to be physically near the associated phone. The completion request indicates that the user is near the phone and the process may continue.

Upon receiving the association request at step S1 (or upon receiving the association complete request at step S3 in the case that an association complete request is required), the cloud service server 32 automatically starts monitoring the extension 21 being associated due to the CTI link 51 established between the cloud service server 32 and the PBX central unit 22. To this end, the cloud service server 32 sends a command to the PBX central unit 22 to monitor the PBX extension 21 associated with the PBX extension telephone number at step S4. Upon receiving the command from the cloud service server 32 at step S11, the PBX central unit 22 starts monitoring the PBX extension 21 associated with the PBX extension telephone number included in the command.

at step S5, cloud services server 32 may selectively send a CTI command to PBX central unit 21 to lock monitored extension 21 to force extension 21 to be locked so that any new external call may occur after a local PBX extension code needs to be manually entered by the user, thereby unambiguously confirming that the user owns extension 21. At step S22, the way in which the CTI command actually causes extension 21 to be locked depends on the implementation of the phone and PBX. For example, this approach may consist in making a third party call control (3PCC) call between extension 21 and a particular prefix interpreted by PBX central unit 22, and then forcing extension 21 to lock itself, or alternatively may translate the call at step S13 through PBX central unit 22 to send a notification directly to extension 21, so extension 21 locks itself.

Step S5 is optional, as step S5 is only applicable to the following environment: technically supports it (the phone must support being locked to prevent use by others than the device owner, and this feature must be available through CTIP BX), and has deployed practices to use native code so users know what their device native code is. When all these prerequisites are met, the cloud service enables the company administrator to activate this security step for the user/device association.

if this step is not enforced, the proximity of the user to the phone must be considered as a sufficient indication that the person is a legitimate person (step S2 is known to enable tracking who received the association code and a prerequisite ensures that only the user of the company can associate the phone of the company).

The native code is local to the enterprise phone installation only and is specific to the phone or phone user (the phone may be shared in a desktop sharing environment, in which case the phone code is not user specific). This code may be selected by the phone user and may be compared to the mobile phone PIN code. This code is unknown to the cloud service and is completely different from the association code sent in step S2.

At step S6, the cloud service server 32 sends a command to the PBX central unit 22 to connect the PBX extension 21 associated with the PBX extension telephone number to the IVR application 33, the command including a public extension telephone number directed to the IVR application 33 managed by the cloud service provider. This may be done by triggering a CTI originating call (MakeCall) on the associated extension.

Upon receiving the command from the cloud service server 32 at step S14, the PBX central unit 22 connects the PBX extension 21 associated with the PBX extension telephone number with the public extension telephone number leading to the IVR application 33.

To this end, the PBX central unit 22 calls the PBX extension 21 associated with the PBX extension telephone number at step S15, and calls the common extension telephone number leading to the IVR application 33 at step S16.

The command to connect the PBX extension 21 to the IVR application 33 may also include the associated context identifier set at step S21.

in addition to IVR public extensions, the associated context identifier may also be sent to the IVR application in MakeCall, for example in the form of DTMF digit sets (e.g. MakeCall dials 0033390677069 × 1234567 #).

The association context identifier may alternatively be sent via DTMF over an established connection.

upon receiving the context identifier number, the PBX central unit 22 automatically dials the context identifier number to the IVR application 33 at step S16. The IVR application may use the context identifier to retrieve the associated context being validated. This method enables the cloud service server 32 to unambiguously identify the incoming call even if the association code generated at step S2 is not unique. This may be done differently by: this is done, for example, by imposing a long association code to the end user, ensuring uniqueness of the association code over the time horizon of possible parallel associations if the cloud service has to provide a high user registration rate; or by using a large number of IVR extensions and assigning parallel registrations to different public numbers.

if the phone is locked in step S22, extension 21 prompts the user to enter his local code at step S24 before extension 21 can actually place a CTI call. At step S25, the user enters a local code and the phone authenticates and unlocks. If the entered code is not valid, the call fails and the association process will stop. This process may be retried by looping over step S3.

At step S31, the call from the PBX central unit 21 arrives at the IVR application of the cloud service. At step S33, the IVR application prompts the user to provide an association code via DTMF or other method that enables digits to be recognized. This is typically done by voice instructions or by displaying a message on the PBX extension interface.

The user enters the association code through an interface of his PBX extension 21. At step S27, the PBX extension 21 transmits the association code dialed by the user over the connection established with the IVR. The association code is typically encoded in a DTMF signal.

upon receiving a call from the PBX extension 21, the IVR application 33 may detect a direct dialing code to call the PBX extension 21. At a subsequent step S10, the number will be associated with a user account.

At step S8, the cloud service server 32 receives the association code through the IVR application 33.

The received association code, which may be related to the association context identifier received at step S31, enables the cloud service server 32 to complete the association.

At step S9, the cloud service server 32 compares the association code received from the PBX extension 21 with the association code sent to the user at step S2.

If the associated context identifier is received by the IVR application 33 at step S31, the cloud service server first retrieves from its memory the association code sent to the user at step S2 based on the context identifier.

if the association code entered by the end user on the phone corresponds to the expected code (sent in step S2 and retrieved by the cloud service), the association is confirmed at step S10 and the cloud service explicitly implements the CTI service on this extension from the user account. If the IVR application detects a direct internally dialed number to call the PBX extension 21 at step S32, the detected direct internally dialed number of the PBX extension 21 is associated with the user account.

At step S36, the cloud service server 32 may send a notification of successful association to the user account through the IVR application.

the elements such as the cloud service server 32, the PBX extension 21 and the PBX central unit 22 may each be, for example, a hardware device such as an Application Specific Integrated Circuit (ASIC) or a combination of hardware and software devices such as a combination of an ASIC and a Field Programmable Gate Array (FPGA) or a combination of at least one microprocessor and at least one memory in which a software module is loaded.

The invention is not limited to the described embodiments. The appended claims should be construed to embody all modifications and alternative constructions that may occur to one skilled in the art and which fall well within the basic teachings set forth herein.

Use of the verbs "comprise", "include" or "include" and their conjugations does not exclude the presence of elements or steps other than those stated in the claims. Moreover, use of the article "a" or "an" preceding an element or step does not exclude the presence of a plurality of such elements or steps.

In the claims, any reference signs placed between parentheses shall not be construed as limiting the scope of the claims.