WO2007036119A1

WO2007036119A1 - A tandem system and a method for calling the route in the tandem system

Info

Publication number: WO2007036119A1
Application number: PCT/CN2006/001924
Authority: WO
Inventors: Guodao Yang; Zhihong Zhao; Weiqiang Zhou
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2005-09-27
Filing date: 2006-08-01
Publication date: 2007-04-05
Also published as: CN1878332A; CN100544456C

Abstract

A method for calling the route in the tandem system and the tandem system includes: set the interface in which the down calls interconnect between the first tandem office and the second tandem office based on the soft-switch; the first tandem office transmits the down calls received by it to the second tandem office connecting with the first tandem office via the interface, and the second tandem office calls the route for the down calls. The present invention can provide at least two routes for the down call, and it can implement the functions of the route backup and the load partaking etc. between the multiple down calling routes. The interface in which the down calls interconnect between the tandem offices of the present invention can use the interface of the SIP-T protocol, and it can implement the route backup and the load partaking of the down calls in the case that it does not add the extra physical device and the connect between the different or identical types of tandem offices. Thereby, it implements the purpose of saving the achieving cost and the maintaining cost of the route backup and the load partaking etc. of the down calls, and improving the reliability of the down calls.

Description

Method for calling route in tandem system and tandem system

Technical field

The present invention relates to the field of network communication technologies, and in particular, to a method for calling routes in a tandem system and a tandem system.

Background of the invention

With the development of telecommunication technology, NGN (Next Generation Network) with softswitch as its core has gradually been applied to telecommunication networks due to its large capacity, high integration, and separation of services, control and bearer.

The networking diagram of the softswitch as the gateway is shown in Figure 1.

In Figure 1, the uplink call to the end office A is called out through the gateway A. In turn, all downstream calls through the gateway are routed through the gateway A to the end office A.

In terms of load sharing and reliability, a dual-plane networking structure is generally adopted. The specific networking is shown in Figure 2.

In Figure 2, for the uplink call of the end office A, since the gateways A and B are two planes that are mutually backed up, there are two routes when calling out from the end office A, that is, route A and route B, route A. Through the access of the gateway A, the route B is accessed through the gateway B.

For a downlink call through the gateway, such as a downlink call from the gateway A to the end office A, there is only one route, that is, the route opposite to the route A.

As can be seen from Figure 2, the current dual-plane networking structure has the phenomenon of uplink call and downlink call asymmetry. The uplink call has backup route protection, while the downlink call does not have backup route protection.

When a traditional switch is not used for networking in a softswitch-based switch, to implement call routing backup, an E1 trunk needs to be added between the gateway A and the gateway B. The E1 is defined by the ITU- T G703, G704, G706 define the communication interface, which not only needs to add additional network construction and maintenance costs, but also does not take full advantage of the NGN network. Summary of the invention

The object of the present invention is to provide a method and a tandem system for call routing in a tandem system. By setting an interworking interface between the tandem offices, the downlink call reliability is improved without increasing the cost of call routing. the goal of.

In order to achieve the above object, a method for routing a call in a tandem system according to the present invention includes: - a, an interface for setting a downlink call interworking between a first gateway based on a softswitch and a second tandem office;

b. The first gateway exchanges the downlink call it receives through the interface to the second gateway to which it is connected, and the second gateway performs call routing for the downlink call.

The technical solution of the method described below is an alternative technical solution.

The two softswitch-based gateways in the step a are: the same type/different softswitch-based gateways;

The first tandem office and the second tandem office are each a tandem office that routes backups or a tandem office that is mutually load-balanced. The interworking interface includes: an interface based on a SIP-T protocol.

The downlink call received by the first gateway in the step b includes: a downlink call received by the first gateway through the interface communicated with the third gateway, and a downlink call received by the first gateway through the downlink call entry. .

The step of the first gateway in the step b to transmit the downlink call received by the first gateway to the second gateway through the interface includes:

The first gateway transmits the downlink call it receives to the second gateway through the interface according to the SIP-T protocol signaling.

The step b specifically includes: the first gateway transmits the downlink call it receives to the second gateway through the interworking interface; the second gateway transmits the downlink call through the relay gateway connected thereto To the end office belonging to the first gateway.

The present invention also provides a tandem system, comprising at least: a softswitch based first gateway and The second gateway of the softswitch is configured to provide an interface for downlink call interworking between the first gateway and the second gateway, where the first gateway receives the downlink call, and passes the downlink call through the The interface is transmitted to the second gateway connected thereto, and the downlink call is routed by the second gateway.

The interface includes: an interface based on a SIP-T protocol.

The softswitch-based gateways are: softswitch-based gateways of the same type or different types.

The tandem system further includes: a trunking gateway belonging to the tandem office, the tandem office is connected to the trunking gateway to which it belongs, and the trunking gateway is connected to one or more end offices;

The second gateway transmits the downlink call received by the interface to the home relay gateway, and the relay gateway routes the downlink call to the corresponding end office.

According to the description of the foregoing technical solution, the present invention can provide at least two routes for the downlink call by setting the interface of the downlink call interworking between different tandem offices, so that routing and backup can be implemented between multiple downlink call routes. Sharing and other functions; By using the SIP-T interface, routing backup and load sharing of downlink calls can be implemented between different types or the same type of tandem office without adding additional physical devices and connections; The technical solution provided by the present invention achieves the purpose of saving the implementation cost and maintenance cost of downlink call routing backup, load sharing, and the like, and improving the reliability of the downlink call. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of networking of a softswitch as a gateway;

2 is a schematic diagram of a dual-plane networking structure;

3 is a schematic diagram of networking of the tandem system of the present invention.

Mode for carrying out the invention

The method of the present invention and the hub of the tandem system are: setting an interface for downlink call interworking between the first tandem office and the second tandem office based on the softswitch, and the first gateway receives the downlink call received by the first tandem office The second gateway connected to the second gateway is transmitted through the interface, and the downlink call is routed by the second gateway.

The technical solutions provided by the present invention are further described below.

An interface for interworking between downlink calls is provided between the two softswitch-based tandem offices of the present invention. The interface for interworking between the downlink calls can be an interface based on the SIP-T (Session Initiation Protocol for Telephones) protocol. The downlink call can be transmitted between the gateways through the signaling of the SIP-T protocol.

The two gateways that have the downlink call interworking interface can be the tandem office that is backed up by each other, or the tandem office that is mutually load balanced.

Since the SIP-T protocol is a standardized protocol widely used for interworking between softswitches, this interface can be used to implement different types or the same type of tandem without adding additional physical devices and connections. Downlink call transmission between offices. For tandem boards of the same type and different types, such as tandem boards with the same model and different models. Of course, the interface for interworking between downlink calls between the two gateways can also be a standardized protocol based on other signaling interactions between softswitches.

After the SIP-T protocol-based interface is set up between the two gateways, such as the first gateway and the second gateway, the first gateway can receive the international/domestic downlink from the downlink call entry. The call is transmitted to the second gateway through the interface of the downlink call interworking. The above downlink call entry is an incoming interface for the first gateway call.

If the first gateway is the primary gateway and the second gateway is the backup gateway, the primary gateway transmits the international/domestic downlink call received from the downlink call portal through the interface of the downlink call interworking. To the tandem office.

After receiving the downlink call through the interface of the downlink call intercommunication, the second tandem office can route the downlink call to the end office belonging to the first tandem office through the relay gateway directly connected thereto, thereby A new route is provided for the downlink call received by the first gateway, which satisfies the requirement of route backup.

If the first tandem office and the second tandem office are mutually load-sharing tandem offices, the first tandem office The international/domestic downlink call received from the downlink call entry is transmitted from the interface of the downlink call intercommunication to the second tandem office. After receiving the downlink call through the interface of the downlink call intercommunication, the second gateway can The directly connected trunking gateway routes the downlink call to the end office belonging to the first tandem office, so that the load between the first tandem office and the directly connected trunking gateway is effectively alleviated, and the load sharing requirement is satisfied. .

In the above description, the downlink call received by the first gateway may also be a downlink call that is received from other gateways through the interworking interface, such as the first gateway through its interworking interface with the third gateway. Receiving a downlink call transmitted by the third gateway, the first gateway can also transmit the downlink call to the second gateway through the interface of the downlink call intercommunication.

The present invention does not change the routing process of the uplink call from the end office to the gateway.

The tandem system provided by the present invention is shown in Fig. 3.

In Fig. 3, the tandem system of the present invention comprises: a gateway A, a gateway B, a trunk gateway belonging to the gateway A, and a trunk gateway belonging to the gateway B. Both the gateway A and the gateway B are both softswitch-based gateways, and the types of gateways A and gateways B may be the same or different.

A gateway based on the SIP-T protocol is set between the gateway A and the gateway B. The gateway A and the gateway B transmit the downlink call through the interface according to the SIP-T protocol.

For the downlink call from the tandem office to the end office, as shown in Figure 3, there are two routes from the gateway A to the end office A, that is, route A and route A', and route A is from the gateway A to the home. In the relay gateway of the gateway A to the end office A, the route A' is from the gateway A to the gateway B to the trunk gateway belonging to the gateway B and then to the end office eight. Route A' and route A are backup routes of each other, and can also share routes with each other.

The above description of the tandem system of the present invention is described by taking two tandem offices as an example, and the tandem system may also include more than two tandem offices. When the tandem system includes multiple tandem offices, the process of implementing call routing for downlink calls between multiple tandem offices is substantially the same as described above, and will not be described in detail herein.

The tandem system of the invention enables route routing of uplink calls and downlink calls The load balancing is used to improve the reliability of the downlink call. Moreover, the present invention fully and effectively utilizes the physical networking of the existing tandem system, and does not need to add additional physical equipment and connections, thereby saving downlink call routing backup and load. Sharing costs and maintenance costs.

While the invention has been described by the embodiments of the invention, it will be understood that

Claims

Rights request

A method for calling a route in a tandem system, characterized in that it comprises:

a. setting an interface for downlink call interworking between the first gateway and the second gateway based on the softswitch;

b. The first gateway transmits the downlink call it receives through the interface to the second gateway to which it is connected, and the second gateway performs call routing for the downlink call.

2. The method of claim 1 wherein:

The first tandem office and the second tandem office are each a tandem office that routes backups or a tandem office that is mutually load-balanced.

3. The method according to claim 1, wherein the interworking interface comprises: an interface based on a SIP-T protocol.

The method of claim 1, wherein the downlink call received by the first gateway in the step b includes: the downlink received by the first gateway through the interface interworking with the third gateway The call, the downlink call received by the first gateway through the downlink call entry.

The method according to claim 1, 2, 3 or 4, wherein the step of transmitting, by the first gateway, the downlink call received by the first gateway to the second gateway through the interface Specifically include:

6. The method of claim 1, 2, 3 or 4, wherein the step b comprises:

The first gateway transmits the downlink call it receives to the second gateway through the interworking interface; The second gateway transmits the downlink call to the end office belonging to the first gateway through the relay gateway connected thereto.

A tandem system, comprising at least a softswitch-based first tandem office and a softswitch-based second tandem office, wherein the first tandem office and the second tandem office are configured The interface with the downlink call intercommunication, the first gateway receives the downlink call, and transmits the downlink call through the interface to the second gateway connected thereto, and the second gateway performs call routing on the downlink call. .

8. The system of claim 7, wherein the interface comprises: an interface based on a SIP-T protocol.

The system according to claim 7, wherein the softswitch-based gateways are: softswitch-based gateways of the same type or different types.

The system according to claim 7, 8 or 9, wherein the tandem system further comprises: a trunking gateway belonging to the tandem office, and the tandem office is connected to the trunking gateway to which it belongs, Following the gateway to connect with one or more end offices;