WO2008071071A1

WO2008071071A1 - A method for controlling flow carried cross-gateway in a office and device thereof

Info

Publication number: WO2008071071A1
Application number: PCT/CN2007/003481
Authority: WO
Inventors: Haopeng Zhu; Yong Zhong; Fang Yin; Xiaolong Guo
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2006-12-11
Filing date: 2007-12-06
Publication date: 2008-06-19
Also published as: CN101202696B; CN101202696A

Abstract

A method for controlling flow carried cross-gateway in an office includes: calculating the usable number of virtual terminal identification between gateways in an office; for a call cross-gateway in an office, when a soft-switch establishes the middle carrier cross-gateway in an office, it selects a pair of gateways according to the usable number; and distributing the usable number of virtual terminal identification in the selected pair of gateways. A device for controlling flow carried cross-gateway in an office is provided.

Description

Flow control method and device for intra-span cross-gateway bearer

Technical field

The present invention relates to the field of communications, and in particular, to a flow control scheme based on IP over El (including IP bearer) between intra-office gateways. Background technique

In the softswitch market promotion, there are some small and medium-sized operators that cannot afford to build and maintain a large IP bearer network. It is hoped that the existing TDM Time Division Multiplexing network can still be used after softswitching. Therefore, an IP over El solution is provided in the related art to meet the needs of these operators.

After the IP over E1 scheme is adopted, the voice will be transmitted by the CRTP (Compressed Real Time Protocol). The cRTP will be the original 40-byte header (IP (Internet Protocol) header 20 bytes. UDP (User Datagram Protocol) The first 8 bytes, the RTP (Real-time Transport Protocol) header is compressed to less than 4 bytes. Take G.729 (No User Plane, User Plane) and AMR (Adaptive MultiRate) 12.2k (with UP), which are commonly used voice codecs. The actual bandwidth after cRTP compression is as follows:

1) G.729 (no UP) bandwidth is 9.6kbps, open VAD (Voice Activity Detection) (using the silence detection technology to save bandwidth, calculate the effective bandwidth according to the mute factor of 0.6), the bandwidth is 5.76kbps;

2) AMR 12.2k (with UP) has a bandwidth of 15.4 kbps, and when VAD is turned on, the bandwidth is 9.24 kbps. Originally a time slot (64kbps) can only carry one call, after cRTP compression:

1) Can carry 6 G.729 calls (VAD off) or 11 G.729 calls (VAD on);

It can be seen that the traffic of the bearer is greatly increased, and the existing TDM network of the operator does not need to be modified. The traffic control needs to be considered after the IP over El solution is adopted on the load-bearing surface. For inter-office cross-gateway calls, the protocol used by the signaling plane has provided inter-office traffic control, such as the Bearer Independent Call Control Protocol (BICC) protocol for GSM/WCDMA networks. The planned CIC (Call Instance Code) effectively controls the number of calls. However, for calls within the intra-office gateway, there is currently no effective means to limit the number of calls. Summary of the invention

The present invention is directed to a flow control method and apparatus for intra-office inter-gateway bearer, which is used to solve the problem of the above-mentioned related art that there is no effective means for limiting the number of inter-station inter-gateway calls.

The specific technical solutions provided by the embodiments of the present invention are as follows:

A flow control method for intra-span inter-gateway bearer includes the following steps:

Determining the available number of virtual terminal identifiers VTID between any two gateways in the office;

When receiving a call across any two gateways in the office, selecting a corresponding gateway pair according to the available number of VTIDs between any two gateways, and establishing an intermediate bearer between the gateway pairs, and one for The flow control device carried in the intra-office gateway includes:

a virtual terminal identifier available number calculation module, configured to calculate an available number of virtual terminal identifiers VTID between intra-office gateways;

a gateway pair selection module, configured to select a corresponding gateway pair according to an available number of VTIDs between any two gateways when receiving a call across any two gateways in the office, and establish an intermediate between the gateway pairs Carry

For a call across the intra-office gateway, instructing the softswitch to select a gateway pair according to the available number when establishing an intermediate bearer between the intra-office gateways; and assigning the available number of virtual terminal identifiers on the off-pair, and then passing The allocation of the number of virtual terminal identifiers controls the traffic carried between intra-office gateways. By assigning a VTID, the present invention implements active flow control of an intermediate bearer (IP over El and IP bearer) on a softswitch. Thus, the use of the softswitch network of the present invention for intra-office cross-border calls can effectively limit the number of calls.

Therefore, the present invention ensures that small and medium-sized operators can not build and maintain a large IP bearer network in the softswitch market, and can use the existing TDM time division multiplexing network.

Other features and advantages of the invention will be set forth in the description which follows, The objectives and other advantages of the invention may be realized and obtained by the structure particularly pointed in the appended claims. DRAWINGS

The drawings described herein are provided to provide a further understanding of the invention, and are intended to be a part of the invention. In the drawing:

1 is a flow chart showing a flow control method for intra-span inter-gateway bearers according to an embodiment of the present invention;

2 is a block diagram showing a flow control device for intra-inter-gateway bearer according to an embodiment of the present invention;

3 is a schematic diagram showing an implementation of a flow control method according to an embodiment of the present invention;

4 shows a schematic diagram of an implementation of a flow control method in accordance with an embodiment of the present invention.

detailed description

The invention will be described in detail below with reference to the drawings in conjunction with the embodiments.

FIG. 1 is a flow chart showing a flow control method for intra-inter-gateway bearer according to an embodiment of the present invention, which includes the following steps:

Step S102, calculating a number of available VTIDs between intra-office gateways; Step S104: For a call between the intra-office gateways, when the softswitch establishes an intermediate bearer between the intra-office gateways, the gateway pair is selected according to the available number;

In step S106, an available number of VTIDs are allocated on the selected gateway pair, and then the traffic carried between the intra-station gateways is controlled by the allocation of the VTIDs.

Through the above-mentioned VTID allocation, the traffic control carried between the intra-office gateways is realized. Calculating the available number may include the following steps: calculating the voice service bandwidth and the data service bandwidth respectively according to the total bandwidth of the intermediate bearer and the ratio of the voice service and the data service to the total bandwidth; and dividing the voice service bandwidth and the data service bandwidth by the voice VTID respectively And the bandwidth of the data VTID, calculate the number of VTIDs supported by the intra-office gateway pair.

The available number is calculated according to the ratio of the number of voice calls to the number of data service calls. Assuming that the total number of calls supported by the intermediate bearer is X, and the ratio of voice and data calls is 3:7, then 0.3*X* voice VTID bandwidth + 0.7*X* data VTID bandwidth is equal to the total bandwidth, where 0.3*X is the voice VTID The number, 0.7*X is the number of data VTIDs. Obviously, those skilled in the art can use other methods to calculate the available number of VTIDs.

The voice VTID bandwidth is related to the codec mode of voice usage. There is a range of variation. The bandwidth referenced when calculating the number of voice VTIDs is an average. Therefore, preferably, when calculating the available number of voice class VTIDs, a certain margin can be reserved for the intermediate bearers.

When selecting a gateway pair, as mentioned above, it should be selected according to the available number, but at the same time, the principle that the gateway path is the shortest, that is, when a gateway pair with multiple paths satisfies the above-mentioned available number of preconditions, it should be selected. The gateway pair on the shortest gateway path. Preferably, a gateway pair with as many possible number of possible and configured gateway paths as possible is selected.

In the above flow control method, the following steps may also be included: If no gateway pair can assign a VTID, the call is removed.

In the above flow control method, the following steps may be further included: an interface needs to be added between the gateway and the softswitch, and when the transmission port in the direction of the adjacent gateway in the same office fails and recovers from the fault, the gateway notifies the softswitch to dynamically adjust the gateway pair. The number of VTIDs that can be assigned. The number of voice and data class VTIDs can be appropriately increased or decreased in the same proportion.

In the above flow control method, the method further includes the following steps: the softswitch sends the virtual terminal identifier to the gateway and performs auditing of the virtual terminal identifier with the gateway; the gateway configures the virtual terminal identifier between the local gateway and the neighboring gateway or the routing gateway. The configuration mode is the same as that of the softswitch, and the virtual terminal is audited with the softswitch. When the transmission port fails and recovers from the fault, the gateway notifies the softswitch to refresh the status of the virtual terminal identifier.

In the above flow control method, the intermediate bearer may be an IP bearer and an IP over El bearer.

2 shows a block diagram of a flow control device 200 for inter-office inter-gateway bearers, including:

The VTID available number calculation module 202 is configured to calculate the available number of VTIDs between the intra-office gateways; the gateway pair selection module 204 is configured to call the inter-office gateways, and the softswitch is instructed to establish an intermediate bearer between the intra-office gateways according to the available number. Select the gateway pair; and

The flow control module 206 is configured to allocate an available number of VTIDs on the selected pair of gateways, and thereby control the traffic carried between the intra-station gateways by allocating the number of VTIDs.

Through the above-mentioned VTID allocation, the traffic control carried between the intra-office gateways is realized. In the above-mentioned flow control device 200, an interface may also be included, which is disposed between the gateway and the softswitch, and is used by the gateway to notify the softswitch to dynamically adjust when the transmission port in the direction of the adjacent gateway is faulty and recovers from failure. The number of virtual terminal IDs that the gateway can assign.

Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general-purpose computing device, which can be concentrated on a single computing device or distributed over a network composed of multiple computing devices. Alternatively, they may be implemented by program code executable by the computing device, such that they may be stored in the storage device by the computing device, or they may be separately fabricated into individual integrated circuit modules, or they may be Multiple modules or steps are made into a single integrated circuit module. Thus, the invention is not limited to any specific combination of hardware and software. It should be within the scope of the spirit of the invention. Specifically, as shown in FIG. 3, by using the management mechanism of the intermediate circuit of the existing TDM bearer, the softswitch (including the softswitch of the GSM/WCDMA/NGN/CDMA/IMS network) configures the VTID between the intra-office gateways (connected The gateways are configured with a corresponding set of VTIDs. The maintenance of the VTID is the same as that of the TID, but it is not required to be sent to the gateway and the TID (Termination Identifier) is audited. The configured VTIDs include: Gateway 1 (¥11012) <--> Gateway 2 (VTID21); Gateway 1 (VTID13) <--> Gateway 3 (VTID31); Gateway 2 (VTID23) <--> Gateway 3 (VTID32) VTIDXY: A set of VTIDs that Gateway X configures in the Y direction of the adjacent gateway.

VTID is divided into two categories, corresponding to voice and data services. Voice VTID estimates the average bandwidth according to the commonly used voice codec (such as AMR and G.729) and the ratio of use. The bandwidth of data class VTID defaults to 64kbps. (釆 G.711 codec). With the bandwidth data of VTID, the number of VTIDs supported by the gateway pair can be obtained based on the total bandwidth of the intermediate carrier and the proportion of voice/data services (or the proportion of calls). When calculating the number of voice class VTIDs, a certain margin can be considered for the intermediate bearer, because after all, the bandwidth of the voice class VTID is an average. The gateway configures the transmission port with maximum bandwidth capacity protection, which can make up for the insufficiency of the softswitch to accurately control the traffic of the intermediate bearer.

For intra-office cross-gateway calls, when the softswitch establishes an intermediate bearer, the appropriate gateway pair is selected according to the shortest path of the gateway path and the number of available VTIDs between the intra-office gateways, and the VTID is assigned on the relevant gateway. If no suitable gateway pair can be assigned a VTID, the call will be removed. The VTID is released when the call with the assigned VTID is removed.

An interface needs to be added between the gateway and the softswitch. When the transmission port in the direction of the adjacent gateway is faulty and recovers, the gateway notifies the softswitch to dynamically adjust the number of VTIDs supported by the corresponding gateway. The number of voice and data VTIDs can be Appropriate increase or decrease in the same proportion.

As shown in FIG. 4, the VTID scheme is also applicable to IP bearers, and supports scenarios in which intra-office gateways are fully interconnected and not fully interconnected through an IP network (ie, an IP network in the figure). For a fully interconnected scenario, the VTID can be configured directly between gateways connected through the IP network regardless of the existence of the IP network. The configured VTIDs include: Gateway l (VTID1) <--> Routing Gateway; Gateway 2 (VTID2) <--> Routing Gateway; Gateway 3 (VTID3) <-> Routing Gateway; VTIDX: Gateway X in the IP Cloud Direction a set of VTIDs configured, where The IP cloud is abstracted as a routing gateway.

For a non-fully interconnected scenario, the IP network can be abstracted as a routing gateway. The VTID is configured between the actual gateway and the routing gateway. According to the traffic distribution, the total bandwidth supported by the IP network is proportionally allocated to the actual gateway. For the bearer between the routing gateways, only the VTID of the actual gateway side is configured. When the softswitch establishes the intermediate bearer, the appropriate gateway is selected according to the number of VTIDs available to the gateway, and the VTID is allocated on the corresponding gateway. If no suitable gateway can assign a VTID, the call will be removed. The VTID is released when the call with the assigned VTID is removed. An interface needs to be added between the gateway and the softswitch. When the transmission port in the direction of the IP network fails and recovers from the fault, the gateway notifies the softswitch to dynamically adjust the number of VTIDs supported by the corresponding gateway. The number of voice and data VTIDs can be the same. Increase or decrease.

There are two reasons for configuring a virtual VTID instead of a virtual CIC between intra-office gateways:

1) The real CIC is bound to the office direction. The virtual CIC must introduce the concept of office direction between the intra-office gateways. It is not necessary. Of course, the virtual CIC may not be linked to the office direction, but the definition of CIC is not inherited. It is too desirable. Moreover, it is too expensive for the gateway to specifically increase the CIC for flow control.

2) Using virtual VTID, inheriting the characteristics of TID, has an irreplaceable advantage, and can easily extend support for VTID on both softswitch and gateway.

On the basis of the above solution, the VTID is completely treated as a TID, and the softswitch is required to issue a VTID to the gateway and perform VTID auditing with the gateway, and the gateway supports configuration between the gateway and the adjacent gateway (or routing gateway). VTID, the configuration mode is the same as that of the softswitch, distinguishes the voice and data services, defines the VTID of different bandwidths, completes the audit of the VTID with the softswitch, and notifies the softswitch to refresh the state of the VTID when the transmission port fails and recovers the fault, instead of adjusting The number of VTIDs.

From the above description, it can be seen that, regardless of the intra-office call or the inter-office call, the present scheme can be applied to control the traffic on the intermediate bearer as long as the inter-office gateway is called. Therefore, the present invention achieves the following technical effects:

The invention realizes active flow control of the intermediate bearer on the soft switch by assigning the VTID. Thus, the softswitch network of the present invention can effectively limit the number of calls for calls within the intra-office gateway. Therefore, the present invention ensures that small and medium-sized operators can not build and maintain a large IP bearer network in the softswitch market promotion, and can use the existing TDM time division multiplexing network.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention. The spirit and scope of the Ming. Thus, it is intended that the present invention cover the modifications and the modifications of the invention

Claims

Rights request

A flow control method for intra-span inter-gateway bearer, comprising the steps of: determining an available number of virtual terminal identifiers VTID between any two gateways in the office;

When receiving a call across any two gateways in the office, selecting a corresponding gateway pair according to the available number of VTIDs between any two gateways, and establishing an intermediate bearer between the gateway pairs, and

2. The flow control method according to claim 1, wherein when determining the available number of VTIDs between the two gateways, the following operations are performed:

Determining a voice service bandwidth and a data service bandwidth according to a total bandwidth carried between the two gateways, and a ratio of a voice service and a data service to the total bandwidth;

Determining a number of VTIDs supported between the two gateways according to a ratio of the voice service bandwidth to a voice VTID bandwidth, and a ratio of a data service bandwidth to a data VTID bandwidth;

The number of available VTIDs between the two gateways is determined based on the number of VTIDs occupied by the voice service call and the data service call.

The flow control method according to claim 2, wherein when the available number of VTIDs between the two gateways is determined, a margin is reserved for the number of VTIDs carrying the voice type service.

4. The flow control method according to claim 1, wherein when the gateway pair is selected, the gateway pair with the most available number of VTIDs is preferentially selected, and it is determined that there are at least two gateways having the same number of available VTIDs. In the right time, the gateway pair with the shortest gateway path is preferentially selected.

The flow control method according to claim 1, wherein when the gateway pair is selected, the gateway pair having the shortest gateway path is preferentially selected, and when it is determined that there are at least two gateway pairs having the same gateway path length , the gateway pair with the most available number of VTIDs is preferentially selected.

The flow control method according to claim 1, wherein if there is no gateway pair to which the VTID can be assigned, the call is removed.

The flow control method according to claim 1, wherein when the one or two gateways of the gateway pair fail and recover from a fault, the VTID of the gateway pair is adjusted accordingly. Use the number.

The flow control method according to claim 7, wherein the number of voice VTIDs and data class VTIDs is increased or decreased in a fixed ratio.

The flow control method according to claim 1, further comprising the steps of: delivering the VTID to the gateway and performing auditing of the VTID with the gateway; and completing the auditing of the VTID by the gateway;

When the transmission port fails and recovers from failure, the status of the corresponding VTID is refreshed according to the notification of the gateway.

The flow control method according to any one of claims 1 to 9, wherein the intermediate bearer is an IP bearer and an IP over E 1 bearer.

A flow control device for inter-span inter-gateway bearer, comprising: a virtual terminal identifier available number calculation module, configured to calculate a virtual terminal identifier between intra-office gateways

The number of available VTIDs;

The flow control device according to claim 11, further comprising an interface, configured to notify the softswitch to dynamically adjust the gateway when the transmission port in the direction of the adjacent gateway is faulty and recovers from failure The number of VTIDs that can be assigned.