DE10235245B4 - Call diversion with path and cost optimization for virtual networking - Google Patents

Abstract

A method for call diversion in virtual networking in a telecommunications network with a calling (11), a called (14), at least one Rufumschaltenden (12, 13) and a call destination telecommunications system (15), wherein a connection between the calling telecommunication system (11) and the call destination telecommunications system (15) is constructed, with the following steps:
a) establishing a connection between the calling telecommunications system (11) and the called telecommunications system (14) via a communication link with one or more call switching telecommunications systems (12, 13);
b) reconnecting the connection to the first call switching telecommunication system (12) of the communication link in the direction of the calling telecommunication system (11);
c) holding and monitoring the connection between the calling and called telecommunications system (11, 14) over the existing communication link by the first call switching telecommunications system (12);
d) signaling a message from the first call switching telecommunication system (12) to the last call switching telecommunication system (13) of the communication link towards the called telecommunication system (14) in the case where a request for call diversion at the called ...

Description

The The present invention relates to a method for call diversion in virtual networking in a telecommunications network according to the Preamble of claim 1.

A TK (telecommunications) system represents a device below represents, the telecommunications terminals (TK terminals) or a telecommunications network to another telecommunications network, usually ISDN, connects. TK terminals are known Phones, networkable computers with running communication software, attendant or Faxes u. a. The term 'gateway' is described below a server in which the transition between the public Telecommunications network (DSS1) and the private telecommunications network (QSIG / PSS1) takes place.

Under a calling telecommunications system is understood here as a system of which an initial connection is established. Such a calling telecommunications system is also referred to below as Originating PINX (Private Integral Services Network Exchange), which is the usual English usage here equivalent. A called telecommunications system is a system from which the rerouting, ie the call forwarding sent away becomes. Such a called telecommunications system is also referred to as Served User PINX. Under a call destination telecommunications system is understood a system in which the destination of call diversion is located. Such a call destination PBX is diverted to PINX in the following called. A telecommunication system in which the call diversion request accomplished will wear in the following the term Rerouting PINX.

It is already known, the QSIG protocol for private telecommunications networks use. When networking PBX systems different Manufacturer makes this protocol a powerful, standardized Signaling system. It is one of the standardization panel ETSI recognized platform for developments in the heterogeneous networking of telecommunications systems. The standardization takes place at international level through ISO / IEC and in the European area through ETSI and ECMA, whereby a mutual harmonization of the Standards is sought. The QSIG protocol is officially called the D-channel protocol at the Q reference point '. The Q reference point is the logical signaling point between two PBX systems. The physical connection is made at the C reference point. QSIG works on the third layer, the network layer of the OSI 7-layer model.

The Connections between the individual network nodes of the private telecommunications network are through leased lines and / or dial-up lines and / or IP (Internet Protocol) routes (about so Realized IP gateways), where any configurations can occur in a network. Such private telecommunications networks are via so-called gateways with the public Telecommunication network connectable. The basics of the QSIG protocol form the Basic Calls (BC), ie the basic messages, and the Generic Function Protocol (GF), ie generic functions.

In BC are the connection establishment and dismantling, as well as the error handling includes. Construction and dismantling of QSIG connections between the individual nodes of the private telecommunications network are accordingly made by means of messages from the BC.

The GF introduces the protocol mechanisms for Supplementary Control Services (complementary services) and Additional Network Features. The Supplementary Services (SS) are features that make up the QSIG protocol for the users of the TK Netzverbundes provides. Under Addtional Network Features (ANF) includes functions that are independent of Users managing connections or the services of the whole Improve network. For Manufacturers to whom the basic features of QSIG (automatic Recall, recall at free, call forwarding, call transfer, Call forwarding, call interception, u. a.) does not suffice, offers QSIG the Generic Functional Procedures (QSIG GF). This standardized Method is used for transporting non-standard functions and for Message handling in the QSIG network.

The following standards describe basic communication in QSIG, the so-called Basic Call: ETS 300 172 Edition 3, ISO / IEC 11 572 Edition 2 and ECMA 143, 3rd Edition. The standards for call diversion, hereafter referred to as diversion, are described in: ETS (European Telecommunications Standard) 300 257, Edition 1; ISO (International Standard Organization) / IEC (International Electrotechnical Commision) 13873, Edition 1 and ECMA (European Computer Manufacturers Association) 174. General information can be found in the Common Information section of QSIG, which includes the standards: ETS 301 820: 2000 and ISO / IEC 15 772: 1998. Additional features can be stored in the QSIG Generic Functions standard, which includes: ETS 300 239, Edition 2, ISO / IEC 11 582, Edition 1 and ECMA 165th

The specified QSIG standards allow the defined functions then use, if the involved terminals in plants switched on are over QSIG lines or QSIG dial-up connections with each other are connected. These QSIG functions can also be used via QSIG dial-up connections, as soon as the operator of the public Network allows for interworking with QSIG. In this virtual networking is thus a free of charge Construction possible. Does it then come to the call, is this fee. Leased lines or leased lines are hereby unnecessary.

Parallel this will be overarching Features in the proprietary TNET protocol offered, where turn the virtual networking with IPN (Intelligent Private Networks) over public Trunks guaranteed becomes. These functionalities are over the QSIG functions over QSIG dial-up connections very similar. This is the abbreviation under TNET the company Tenovis for their digitized private telephone network with intelligent features Understood.

In huge domains in which many telecommunications systems are networked, there are central components such as voice mail, interactive voice recognition systems, Unified Messaging Systems a., common to all PBXs should be used. Become these central components in the virtual network reached, thereby immediately charges, since these directly with CONNECT reply.

Of the Diversion's QSIG standard recognizes delayed call forwarding or call forwarding (Late Release Handling) for call forwarding (CFNR - Call Forwarding No Reply), which means that the first connection is not triggered will and after the feedback is decided by the second connection attempt, which connection path trigger is.

As well Diversion's QSIG standard knows an optimization with a 'piecemeal' approach Route change ' which is referred to in the following as forward switching. there the Served User PINX becomes the Rerouting PINX. Will this rerouting request rejected by the Originating PINX, because this example, the Service not supported, so leads the Served User PINX through Forward Switching (Rerouting) itself. The negative attachment is over the call forwarding informed.

This Forward switching can also be enforced in the Served User PINX, by suppressing the sending of the rerouting request and the call forwarding is carried out directly itself. In this context But a call diversion with decision is just as impossible as a later one Trigger the Connection (late release).

It It is an object of the invention to provide a method which a route optimization in the QSIG network and a path and cost optimization in virtual networking via QSIG dial-up lines guaranteed.

These The object is achieved by a method according to claim 1.

One Core idea of the method according to the invention is doing that the late release handling is done and the first connection is not triggered. After the late release Handling and optimization handling will be the first Reconnected connection. This is after a call via QSIG to a Served User PINX a return to Originating PINX made. To avoid looping and a Dismantling existing unnecessary connections Now the path optimization can be realized by that again A rerouting within the Rerouting PINX with the destination towards the Served User PINX is taking place. This does not cause degradation existing connections, but these will continue used. This is a solution been found, in which in a network network on the one hand, a route optimization and conversations over QSIG dial-up lines (virtual networking) a route optimization and cost optimization without renewed fees achieved by repeated connection establishment.

The Method based on Generic Functions (ETS 300239 ISO / IEC 11582, ECMA 165), the ROSE (Remote Operation Service Element) concept (CCITTX.219 / X.229), ASN.1 (X.208 / X.209), the Common Information (ETS 301 820: 2000, ISO / IEC 15772: 1998) and Diversion (ETS 300 257, ISO / IEC 13873, ECMA 174).

The ROSE concept defines the environment to realize additional functions. It arrives It is also used to control vendor-specific supplementary services. The ROSE actions (RO-Invoke, RO-Result, RO-Error, RO-Reject-U, RO-Reject-P) are mapped to four protocol elements. Such protocol elements are referred to as Application Protocol Data Unit (APDU). The four protocol elements are: RO-Invoke, RO-Return-Result, RO-Return-Error, RO-Reject. The ROSE protocol elements are transmitted using the FACILITY information element. The FACILITY information element is transmitted either with basic calls, ie messages such as SETUP, ALERT, CONNECT, PROGRESS or DISCONNECT or, if no basic calls are available, with the message FACILITY then to be used. There may be multiple ROSE protocol elements in a FACILITY information element.

The Generic Functions and ROSE allow the definition of features both at the level of standardization and the definition proprietary Characteristics. The method described here 'Path and cost optimization for virtual Networking in the QSIG network thus represents a proprietary feature Thus, the feature 'path- and cost optimization 'in a QSIG network and a virtual QSIG network made.

After that will signal the message from the first call switching Telecommunications system, so the first Rerouting PINX out. This is supported on the one hand by the QSIG standard, for others, an upstream decision-making body is created, which over the optimal communication route to Diverted to PINX in the sense a path and cost optimization decides. After the late Release handling performed and the first connection establishment was not triggered, the first connection establishment from the point of view of optimizing the communication route be reused. So there is no renewed connection instead of, whereby in the network network a route optimization is achieved. For call setups via QSIG dial-up lines (virtual networking) becomes a route optimization and a cost optimization without renewed fees reached.

Prefers the message FACILITY with the information element DivOptimisation.inv transported. This message with newly defined manufacturer-specific Content DivOptimisation.inv is used in private networks between the Transfer plants.

It Furthermore, it is advantageous that the message FACILITY with the facility information element callRerouting.inv with the encoding RejectAnyUnregonizedOperation is sent. This forces the Rerouting PINX to the method of the invention unsupported, a reject APDU to the Served User PINX sends, what this then as rejection evaluates the call forwarding. Thus, the telecommunications systems in the inventive method included, which do not support this.

One Another particular advantage lies in the fact that the retransmission takes place with a message coming from the information element FACILITY [callRerouting.inv] exists. This again corresponds to the QSIG standard and guaranteed a transparency of the procedure in the QSIG network and between Systems of different manufacturers.

In In practice, the communication link between the PBXs usually QSIG leased lines and / or dial-up connections. In order to becomes the method according to the invention both in private networks (leased lines) and public Networks (dial-up connections) harnessed, although in the latter the QSIG protocol by the appropriate network operator (carrier), such. B. ARCOR supports becomes.

From It is particularly advantageous if the communication path between the PBX systems completely or partially over QSIG IP gateways or the Internet is guided. The mentioned gateways offer accesses too widespread networks, so that the inventive method for special many users can be reached and used.

While the calling PBX be identical to the call-switching PBX can, the call destination PBX can be identical to the call switching and / or the called telecommunications system. Regardless of which of the PBXs, So Rerouting PINX, Served User PINX or Diverted to PINX the Call destination contains, is thus a corresponding flexibility of the method according to the invention guaranteed.

To the Signaling messages via ISDN become exclusive D-channel connections used, so that the inventive method both with and without traffic channel occupancy (ISDN B channels), ie as a pure signaling connection, can be performed.

in the The following is the method according to the invention based on an embodiment explained in more detail. It demonstrate:

1 the process sequence according to the invention on the basis of exchanged between the participating PBX messages messages in ways and cost optimization in a QSIG network and

2 a QSIG protocol model as a block diagram with the new feature SS control for call diversion.

The 1 shows the inventive method based on the between the participating telecommunications systems Originating PINX 11 , Rerouting PINX 12 and 13 , Served User PINX 14 and Diverted-to PINX 15 ,

The in the messages FACILITY, SETUP and CONNECT in the course of the procedure ROSE operations are respectively below the corresponding messages assigned to the directional arrow. These ROSE operations are in detail: callRerouting.inv (Invoke), callRerouting.rr (Return Result), DivOptimisation.inv (Invoke), divertingLegInformation1.inv (Invoke), divertingLegInformation2.inv (Invoke) and divertingLegInformation3.inv (Invoke).

Uses a caller now from the Originating PINX 11 , So the calling PBX, z. B. the service of a voice-controlled information system with call destination in the Served User PINX 14 , it can be provided that a menu item can be reached via another telephone number which is in the Diverted-to PINX 15 is included. If such a call forwarding take place, at least the rerouting systems Rerouting PINX must be in a domain 12 and Rerouting PINX 13 have implemented this proprietary solution. A minimal configuration would be the summary of the Originating PINX 11 and Rerouting PINX 12 , as well as a summary of the Rerouting PINX 13 , Served User PINX 14 and Diverted-to PINX 15 ,

After establishing the call via QSIG to the Served User PINX 14 finds a way back towards originating investment to the Rerouting PINX 12 instead of. The call setup complies with the QSIG standard (SETUP, ALERT, CONNECT). After retransmitting to the Rerouting PINX 12 with a rerouting request FACILITY [callRerouting.inv], after acknowledgment of this message by FACILITY [callRerouting.rr], a rerouting within the Rerouting PINX 12 with the goal in Diverted-to PINX 15 occur. This does not lead to the reduction of this existing connection, but this connection will continue to be used. The existing, paid virtual connection is then no longer broken down, but within the Rerouting PINX 12 controlled brought into a waiting position.

Can be found that the Rerouting PINX 12 turn a call forwarding to the Diverted-to PINX 15 towards Rerouting PINX 13 and thus again needs a new virtual connection, the old, still in the waiting position existing virtual connection is used again and thus saved a renewed Zweitaufbau, which would be chargeable again. Line L indicates the process status after which route and cost optimization is initiated.

The new connection establishment taking advantage of the existing connection becomes from the Rerouting PINX 12 controlled and the new message FACILITY [DivOptimisation.inv] to Rerouting PINX 13 cleverly. When the request arrives at the QSIG line in the Rerouting PINX 13 the optimization is initiated. The Rerouting builds PINX 13 a D-channel connection to Diverted-to PINX 15 on and the connection to the Served User PINX 14 using DISC (DISCONNECT). All further messages (ALERT, FACILITY [divertingLegInformation1.inv], as well as the switching through of CONNECT [divertingLegInformation3.inv] finally again correspond to the QSIG standard.) The desired service of the voice-controlled information system is thus for the caller under the forwarded telephone number without interrupting the connection reachable.

The procedure described can not be achieved with a forward switching in the Rerouting PINX according to QSIG standard, since the rerouting system PINX 13 , in which the forward switching is carried out, no knowledge of later algorithms from the Rerouting PINX 12 can own.

The method uses only D-channel connections for signaling. The call forwarding information with the new facility message with content [DivOptimisation.inv] is transmitted in a newly defined manufacturer-specific ROSE operation. The Facility information element is sent with the coding SourceEntity: END PINX and DestinationEntity: EndPINX as coding for the Network Facility Extension. The coding of the facility information element for the interpretation APDU is with RejectA nyUnrecognizedOperation selected.

The following table formally lists the contents of the private extensions of the QSIG operations. The formal definition not only defines the content of the signaling, but also a so-called identifier that uniquely identifies this signaling information within QSIG:

2 shows the QSIG protocol model as a block diagram with a Coordinate Function 21 , call control 22 and a number of SS (Supplementary Service Control) controls 23 , The new feature 'Call diversion with route and cost optimization in virtual networking' will become the SS control for call diversion 23 ' controlled.

The identifier includes other service elements such as ROSE (Remote Operation Service Element), ACSE (Access Control and Signaling Element) and DSE (Distributed Systems Environment). The call forwarding method according to the invention 23 ' is with the coordinating function 21 connected via which the SS control for call forwarding 23 ' uses the services of ROSE. The coordination function 21 continues with the GFT (Generic Functional Transport Control) control 24 connected. The GFT control 24 shows two types of services. On the one hand, the transport service for protocol elements between functions that run on different PBXs, and on the other the establishment and removal of connections without traffic channel assignment, which are signaling connections. The GFT control 24 is with a protocol control (Protocol Control) 25 connected, which performs the transmission of protocol elements between adjacent PBXs and the establishment and removal of signaling links between adjacent PBXs. Also call control 22 is with the coordinating function 21 and protocol control 25 connected. The protocol control 25 transfers or receives data. The Signaling Carriage Mechanism (SCM) 26 , So the signaling mechanism, then gives the messages on a line 27 or receive them from the line 27 ,

At It should be noted that all of the above Parts for seen alone and in any combination, especially the The details shown in the drawings claimed as essential to the invention become. amendments this is familiar to the person skilled in the art.

11

calling telecommunications system

12 13

Rufumschaltende telecommunications system

14

Recalled telecommunications system

15

Call destination telecommunications system

21

coordinating role

22

call control

23 23 ', 23' '

SS control

24

GFT control

25

protocol control

26

signaling mechanisms

27

management

Claims (5)

Method for call diversion in virtual networking in a telecommunication network with a calling ( 11 ), a called ( 14 ), at least one call switching ( 12 . 13 ) and a call destination telecommunications system ( 15 ), whereby a connection between the calling telecommunication system ( 11 ) and the call destination telecommunications system ( 15 ), comprising the following steps: a) establishing a connection between the calling telecommunication system ( 11 ) and the called telecommunications system ( 14 ) via a communication link with one or more call switching telecommunications systems ( 12 . 13 ); b) reconnecting the connection to the first call switching telecommunication system ( 12 ) of the communication link in the direction of the calling telecommunication system ( 11 ); c) holding and monitoring the connection between the calling and called telecommunications equipment ( 11 . 14 ) over the existing communication link through the first call-switching telecommunications system ( 12 ); d) signaling a message from the first call switching telecommunication system ( 12 ) to the last call switching telecommunication system ( 13 ) of the communication link in the direction of the called telecommunication system ( 14 ) in the case where a call diversion request is made at the called telecommunication facility ( 14 ) is present; and e) triggering the connection between the last call switching telecommunication system ( 13 ) and the called telecommunications system ( 14 ) and sending a further connection request from the last call switching telecommunication system ( 13 ) to the call destination telecommunications system ( 15 ) in response to the received message. Method according to Claim 1, characterized in that the signaling of the message from the first call-switching telecommunications system ( 12 ) is controlled out. Arrangement for carrying out the method according to one of the preceding claims, characterized in that the communication path between the telecommunication systems ( 11 . 12 . 13 . 14 . 15 ) QSIG leased lines and / or dial-up connections. Arrangement for carrying out the method according to one of Claims 1 to 2, characterized in that the communication path between the telecommunication devices ( 11 . 12 . 13 . 14 . 15 ) runs in whole or in part via QSIG IP gateways via the Internet. Arrangement for carrying out the method according to one of claims 3 or 4, characterized in that the calling ( 11 ) identical to the Rufumschaltenden telecommunications system ( 12 ) and the call switching ( 13 ), which are called ( 14 ) and the call destination telecommunications system ( 15 ) are identical.