CN101729397B - Method for controlling promotion and degradation of service quality - Google Patents

Abstract

The invention discloses a method for controlling service quality downgrading. The resource initialization request sent by the service control function entity SCF to the policy decision-making function entity PD-FE carries the maximum bandwidth allowed to be lent by the media stream; if the media stream is served If the quality of QOS is downgraded, the PD-FE will complete the QOS downgrade of the media stream according to the maximum bandwidth allowed to be lent by the media stream. The present invention degrades the QoS of the degraded object by determining the degraded object, realizes accessing as many sessions as possible in a network environment with limited resources, and redefines the QoS-Downgradable parameter, which is comparable to the existing QoS-Downgradable parameter In contrast, the degree of degradation is no longer completely determined by the network, which meets the individual requirements; the default selection is to allow QoS degradation and does not require subsequent upgrades, which meets the requirements for multi-service acceptance and makes full use of network resources; provides QoS upgrades The choice meets the needs of different sessions.

Description

A Quality of Service Upgrading and Decreasing Control Method

technical field

The present invention relates to the technical field of resource admission control, in particular to a method for controlling service quality downgrading.

Background technique

In order to solve the problem of resource management in the next generation network, ITU-T (International Telecommunication Union Telecommunication Standardization Group) proposed a resource admission control function (RACF) that supports end-to-end quality of service (QoS) and realizes network border control. It is applicable to many different services and different transmission technologies.

The RACF processes the service admission request according to the current network resource status. Specifically, when the Policy Decision Functional Entity (PD-FE) in RACF receives the Resource Initiation Request (Resource InitiationRequest), it authorizes and queries the Transport Resource Control Functional Entity (TRC-FE) for the availability of resources; if available resources If it is sufficient to satisfy the resource initialization request, make a reservation and/or promise decision, and request the policy enforcement function entity (PE-FE) to allocate resources; otherwise, reject or perform QoS downgrade processing on the resource initialization request.

In order to realize QoS downgrading, ITU-T defines a QoS-Downgradable parameter in the RACF document, which is used to indicate whether the session allows downgrading, as the basis for the network to select the downgrading object. The QoS-Downgradable parameter is carried in the resource initialization request and sent to PD-FE.

The QoS-Downgradable parameter is defined as follows:

Enumeration type, providing usage information of IP flow;

The specific values are as follows:

NORMAL(0): Provides normal resource allocation;

MAY_DOWNGRADE(1): If resources are insufficient, QoS can be downgraded to traditional IP service quality, and there is no need to reject the session;

The default value of the QoS-Downgradable parameter is NORMAL.

However, the above definition method has the following disadvantages:

1. There is no choice of downgrading degree, only pointing out that QoS can be downgraded to traditional IP service quality when resources are insufficient;

2. The default value is NORMAL. In the case of limited network resources, this default value greatly reduces the session access rate and cannot make full use of network resources;

3. Lack of options for QoS upgrades.

Moreover, when network resources are limited, PD-FE can only lower the QoS of the resource initialization request to access the request as much as possible. FE can only reject the request, and cannot access as many requests as possible by using existing network resources.

Contents of the invention

The technical problem to be solved by the present invention is to provide a quality of service upgrade and upgrade control method to solve the problem that the available resources in the network are not enough to meet the resource request, and the resource request does not allow QoS downgrade or the resource request cannot be satisfied after the downgrade , the problem with the request could not be accessed.

In order to solve the above technical problems, a method for controlling degradation of service quality in the present invention includes:

The resource initialization request sent by the service control function entity SCF to the policy decision function entity PD-FE carries the maximum bandwidth allowed to be lent by the media stream;

If the quality of service QOS is degraded for the media stream, the PD-FE completes the QOS degrade for the media stream according to the maximum bandwidth allowed to be lent by the media stream.

Further, when the available resources cannot meet the resource requirements of the resource initialization request, if the media stream allows QOS downgrade, perform QOS downgrade on the media stream;

If the media stream does not allow QOS downgrading or the resource requirements of the resource initialization request cannot be met after the QOS downgrading of the media stream, the PD-FE selects the downgrading object, and performs the process on the selected downgrading object according to the maximum bandwidth allowed to be lent by the downgrading object. QOS downgrade;

The downgrade object is other media streams owned by the user who initiates the resource initialization request and/or one or more of the media streams owned by other users.

Further, the resource initialization request also includes the requested resource allocation, the maximum releasable resource, media priority and QoS-Downgradable parameters.

Further, resource requirements=resources requested for allocation−maximum resources that can be released.

Further, after the PD-FE learns that the current available resources cannot meet the resource requirements, it judges whether the resource requirements are less than the sum of the available resources and the maximum resources that can be released by sessions whose overall priority is lower than the session to be admitted corresponding to the resource initialization request, and if so, Then perform the operation of selecting a downgraded object; otherwise, reject the resource initialization request.

Further, the overall priority is the priority of the session determined according to one or more of the media priority, the total bandwidth that has been lent by the media stream included in the session, and the bandwidth that can be lent by the media stream included in the session.

Further, overall priority=media priority×(total bandwidth already lent/bandwidth available for lending+1).

Further, the downgrade object is registered in a downgrade record, allowing the media flow of the QOS downgrade session;

The specific method of selecting the downgraded object is as follows:

PD-FE judges whether there is a session whose overall priority is lower than the session to be admitted among all the sessions recorded in the downgraded record owned by the user who initiated the resource initialization request. The media streams of one or more sessions whose overall priority of the user initiating the resource initialization request is lower than that of the session to be admitted are sequentially downgraded.

Further, after downgrading the media streams of one or more sessions whose overall priority of the user who initiates the resource initialization request is lower than that of the session to be admitted, if the available resources still cannot meet the resource requirements of the session to be admitted, the user who belongs to other users The media streams of one or more sessions whose overall priority in the downgraded record is lower than that of the session to be admitted are downgraded.

Further, the transmission user identifier, resource control session identifier, overall priority, QoS-Downgradable parameter, stream number, maximum bandwidth allowed to be lent by the media stream and the already lent bandwidth of the media stream are recorded in the degraded record;

When establishing a session, record the session that allows downgrade in the downgrade record; and after downgrading the session, modify the overall priority and media stream description of the session in the corresponding entry of the downgraded session, and record the historical operations performed on the session.

Further, the QoS-Downgradable parameter identifies whether QoS downgrading is allowed for the session, and the values include: not allowing QoS downgrading, allowing QoS downgrading and not requiring subsequent upgrades, and allowing QoS downgrading and requiring subsequent upgrades; the default value is allowing QoS downgrading and not requiring Subsequent upgrades.

Further, a quality of service upgrade control method,

After downgrading the QoS of the session, if the PD-FE learns that the available resources increase, it will select the session that needs to be upgraded among the downgraded sessions, and upgrade the media stream of the session in order of overall priority from high to low.

Furthermore, before PD-FE upgrades the media stream of the session, it also judges whether the available resources are greater than the total resources lent by the session to be upgraded, and if so, returns all the resources lent from the session to be upgraded; All available resources are returned to the session to be upgraded.

Further, the PD-FE queries the downgrade record, and selects the session that needs to be upgraded among the downgraded sessions; the PD-FE judges whether the session needs to be upgraded according to the QoS-Downgradable parameter of the session in the downgrade record, and according to the overall priority of the session in the downgrade record , upgrade the media streams of the session in descending order.

Further, the QoS-Downgradable parameter identifies whether QoS downgrading is allowed for the session, and the values include: not allowing QoS downgrading, allowing QoS downgrading and not requiring subsequent upgrades, and allowing QoS downgrading and requiring subsequent upgrades; the default value is allowing QoS downgrading and not requiring Subsequent upgrades.

In summary, the present invention degrades the QoS of the degraded object by determining the degraded object, realizes accessing as many sessions as possible in a network environment with limited resources, and redefines the QoS-Downgradable parameter, which is different from existing Compared with the QoS-Downgradable parameter, the degree of downgrading is no longer completely determined by the network, which meets individual requirements; the default selection is to allow QoS downgrading without subsequent upgrades, which meets the requirements for multi-service acceptance and makes full use of network resources; provides It provides the choice of QoS upgrade and meets the needs of different sessions.

Description of drawings

Fig. 1 is a flow chart of PD-FE determining the degraded object in the present invention;

Fig. 2 is the flow chart of PD-FE determining upgrade target in the present invention;

Fig. 3 is an interactive diagram of the implementation process of upgrading and downgrading in the present invention.

Detailed ways

In the present invention, RACF reduces the requested resource according to the corresponding QoS-Downgradable parameter of the resource request, or properly allocates some resources from other sessions, accesses the session as much as possible, and allocates resources from other sessions after the network resources are sufficient. The resources are returned to the original downgraded session.

Aiming at the defects of the QoS-Downgradable parameter defined in the RACF document in the prior art, the present invention redefines the parameter. At the same time, it explains the timing of upgrading and upgrading QoS, the selection of upgrading and upgrading objects, and the specific execution process of upgrading and upgrading.

The present invention not only redefines the QoS-Downgradable parameter, but also adds a new parameter maximum bandwidth (Maximum Tolerable Bandwidth Loss) that the media stream allows to lend in the parameter set passing through the Rs reference point. The maximum bandwidth can be determined by operators or users themselves. The redefined QoS-Downgradable parameters are as follows:

QoS-Downgradable parameter: enumeration type, indicating whether the session allows QoS downgrading.

The specific values are as follows:

0: The session does not allow QoS downgrade;

1: The session allows QoS downgrade and does not require subsequent upgrades;

2: The session allows QoS downgrade and requires a subsequent upgrade.

The default value of the QoS-Downgradable parameter is 1.

In the present invention, from the perspective of making full use of network resources, the default value of the QoS-Downgradable parameter is set to allow QoS downgrading, and the sessions that prohibit QoS downgrading are only limited to high-priority sessions and privileged users (such as VIP users) .

For the specific execution process of QoS upgrade and upgrade, the resource modification (PD-FE Requested Resource Modification) process initiated by PD-FE is adopted, and the allocated resources are modified in time according to the status of network resources, without the need for SCF (service control function entity) and CPE (client end) equipment) participation.

Specifically, when the PD-FE learns that the currently available resources cannot satisfy the resource request, it will select one or more degraded objects and release enough resources to successfully allocate resources for the requested session. The above-mentioned demotion object may be the requested session itself, or an existing session with a lower priority than it.

When selecting a QoS downgrading object, the priority of the session is usually used as a criterion for judging. A session may contain multiple media streams. If only a certain media priority (Media Priority) of the session is considered, due to the limited division of media, the screening result may contain multiple objects of the same priority; in addition, only based on the media priority Judgment is also very limited. For this reason, the present invention proposes the concept of overall priority (Overall Priority), and the following factors need to be considered simultaneously for overall priority:

1. Media priority: such as TDR/ETS (Emergency Telecommunication Service/Telecommunications for Disaster Relief, emergency telecommunication service/disaster recovery telecommunication service), etc., the level of media priority is divided into 0~7;

2. Total Bandwidth Loss lent: the sum of the bandwidth lent by the media streams included in the session, the larger the value, the higher the overall priority;

3. Potential Bandwidth Loss: The sum of the bandwidth that can be lent by the media streams included in the session. The larger the value, the lower the overall priority.

Wherein, the bandwidth that can be lent = the maximum bandwidth allowed to be lent - the total bandwidth that has been lent.

Can adopt different methods under different circumstances, determine overall priority according to above-mentioned three factors, do not limit in this text, only provide a kind of simple calculation method at this: overall priority=media priority * (lent total bandwidth/loanable bandwidth+1).

In order to record the historical operations performed on the session, RACF in the present invention reserves a corresponding downgrading record (Downgrading Record) for each session that allows downgrading, and records the release of specific media stream resources as the basis for subsequent operations (further downgrading or upgrading) .

The content of the downgrade record includes the following aspects:

1. Transport Subscriber Identifier: used to identify the CPE to which the session belongs;

2. Resource Control Session Identifier (Resource Control Session Identifier): used to identify the session;

3. Overall priority: used to identify the priority of the session;

4. QoS-Downgradable parameter: indicates whether the session allows QoS downgrading;

5. Media Flow Description:

Flow Number: used to identify the media stream in the session;

The maximum bandwidth allowed to be lent by the media stream;

Bandwidth Loss: The bandwidth that has been lent by the media stream.

The downgrade record not only records the sessions that have been downgraded, but also includes sessions that allow downgrade but have not been downgraded.

In practical applications, when RACF accepts a session, it records the session that can be downgraded into the downgrade record according to the value of the QoS-Downgradable parameter of the session. Sort in low order to improve the efficiency of subsequent retrieval.

The specific embodiment of the present invention is described in detail below in conjunction with accompanying drawing:

Fig. 1 is the determination process of the degraded object of the present invention, and the specific steps are as follows:

101: After the PD-FE receives the resource initialization request sent by the SCF, it queries the resource availability from the TRC-FE;

The resource initialization request includes the resources allocated by the session to be admitted, the maximum resources that can be released by the session to be admitted, the media priority, the maximum bandwidth allowed to be lent by the media stream, and the QoS-Downgradable parameter.

102: After the PD-FE learns that the current available resources cannot meet the resource requirements of the session to be admitted, it judges whether the following conditions are met: request for resource allocation - maximum resources that can be released by the session to be admitted < available resources + sessions with a lower overall priority The most resources released (condition 1);

This condition ensures that the resource request can be satisfied after downgrading. The maximum resource that can be released by the session to be admitted in the above condition 1 is equal to the maximum bandwidth allowed to be lent by the session.

PD-FE can subtract the lent bandwidth from the maximum bandwidth allowed to be lent by the media flow of the session whose overall priority is lower than that of the session to be admitted in the degraded record, to obtain the lentable bandwidth, and then calculate the lentable bandwidth of each session The allocated bandwidth is accumulated to obtain the maximum resources that can be released by sessions with a lower overall priority in the condition.

103: If condition 1 is not met, the request is directly rejected to avoid unnecessary and invalid downgrade;

104: If the condition 1 is met, judge whether the QoS-Downgradable parameter is equal to 0 to judge whether the session to be admitted allows QoS downgrading, and if the session to be admitted allows downgrading, execute step 105; otherwise, jump to step 107;

105: The session to be admitted is downgraded, and the reduced bandwidth of each media stream in the session to be accepted does not exceed the maximum bandwidth allowed by each;

106: Determine whether access is possible after downgrading, if yes, access, create a downgrade record for the session, and end; otherwise, execute step 107;

107: Determine whether the overall priority of the session to be admitted is lower than all other sessions recorded in the downgraded records owned by the user, and if the user has a lower overall priority session, perform step 108; otherwise, skip to step 110;

108: Downgrade the media streams of one or more of these sessions in the order of overall priority from low to high, and modify the corresponding entries of the downgraded sessions in the downgrade record, including: the overall priority of the session and the media stream describe;

109: Determine whether access is possible after the downgrade, if yes, then end, and when the session allows downgrade, create an entry for it in the downgrade record; otherwise, execute step 110;

110: Downgrade the media streams of one or more sessions recorded in the downgrade record that have a lower overall priority belonging to other users, and modify the corresponding entries of the downgraded sessions in the downgrade record;

111: Access the session after the downgrade is completed, and create an entry for it in the downgrade record when the session is ended and downgrade is allowed.

Note that since the overall priority is dynamically changed with the downgrade process, when judging whether condition 1 is true, if the session to be admitted itself allows downgrade, the overall priority of the downgraded session should be pre-calculated, and then filtered according to this priority Existing sessions, calculate the maximum resources they can release.

To sum up, the basic principle for judging the downgraded object is to first consider downgrading the session to be admitted, and then consider downgrading other sessions owned by the requesting user; if the resource requirements cannot be met, then downgrade the sessions belonging to other users , that is, to minimize the scope of influence.

Fig. 2 is the determination process of the upgrading object of the present invention, and concrete steps are as follows:

201: When the resources of one or more existing sessions are successfully released, the PD-FE learns that the amount of currently available resources has increased;

202: PD-FE queries the downgrade record, filters out the sessions that need to be upgraded (the session with QoS-Downgradable parameter=2), and selects the downgraded session with the highest overall priority as the session to be upgraded;

203: PD-FE judges whether the following condition is met, available resources > total resources lent before the session to be upgraded (condition 2), if satisfied, perform step 204; otherwise, perform step 206;

204: PD-FE initiates a QoS upgrade process, returns all resources borrowed from the media stream of the session to be upgraded, and modifies the corresponding entry of the session in the downgrade record;

205: If there are still resources remaining, return to step 202, and select the next session to be upgraded; if there are no resources remaining, then end;

206: The PD-FE initiates a QoS upgrade process, returns the resources to the maximum, and modifies the corresponding entry of the session to be upgraded in the downgrade record at the same time, and ends.

Figure 3 is the execution flow of upgrading and downgrading in the present invention. PD-FE requests PE-FE to modify resources. The specific steps are as follows:

301: TRC-FE sends a resource report to PD-FE to trigger resource modification. The resource report can be a direct resource status information report, or a reply message, such as the current resource cannot access the session to be accepted or release a resource for a session Success, etc. For the reply message, in order to reduce the number of subsequent queries of the PD-FE to the TRC-FE, the reply message can add the current actual available bandwidth information;

302: The PD-FE makes an upgrade or downgrade decision according to the method described in Figure 1 or Figure 2, and calculates the modification amount;

303: PD-FE initiates a resource modification request (Resource Modification Request) to PE-FE, and notifies PE-FE of the modification amount;

304: After the PE-FE completes the modification, it returns a resource modification response (ResourceModification Response) to the PD-FE;

305: The PE-FE updates the modified resource status to the TRC-FE;

306: The update is completed, and the TRC-FE returns a resource modification reply.

The present invention can also have other representations. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and deformations according to the present invention. These corresponding changes and deformations All should belong to the scope of protection of the appended claims of the present invention.

Claims (10)

1. the degradation control method of a service quality is characterized in that,

Business control function body SCF carries Media Stream and allows the maximum bandwidth of lending, resource, releasable maximum resources, media priority and the QoS-Downgradable parameter that request distributes in the initializing resource request that sends to policy deciding functional entity PD-FE; Whether the session of said QoS-Downgradable parameter identification allows the QoS degradation, and value comprises: do not allow the QoS degradation, allow the QoS degradation and do not need subsequent upgrade and allow the QoS degradation and need subsequent upgrade; The acquiescence value is for allowing the QoS degradation and not needing subsequent upgrade;

If said Media Stream is carried out service quality QOS degradation, then said PD-FE accomplishes the QOS degradation to said Media Stream according to the maximum bandwidth that said Media Stream allows to lend;

When available resources can not satisfy initializing resource requested resource demand,, then said Media Stream is carried out the QOS degradation if said Media Stream allows to carry out the QOS degradation;

If said Media Stream does not allow to carry out QOS degradation or to still not satisfying said initializing resource requested resource demand behind the said Media Stream QOS degradation; Then said PD-FE selects the degradation object; Allow the maximum bandwidth of lending based on said degradation object, selected degradation object is carried out the QOS degradation;

Said degradation object is one or more in other Media Stream that had of the said initializing resource requesting users of initiation and/or the Media Stream that other user had.

2. the method for claim 1 is characterized in that,

Resource-releasable maximum resources that resource requirement=described request is distributed.

3. method as claimed in claim 2 is characterized in that,

After said PD-FE knows that current available resource can not satisfy resource requirement; Judge that whether resource requirement is less than the low releasable maximum resource sums of session of the corresponding session to be accepted of the said initializing resource request of available resources and whole priority ratio; If satisfy, then carry out the operation of said selection degradation object; Otherwise, refuse said initializing resource request.

4. method as claimed in claim 3 is characterized in that,

The priority of the one or more definite session in the loanable bandwidth of Media Stream that said whole priority is comprised for the total bandwidth of having lent according to media priority, Media Stream that session comprised and session.

5. method as claimed in claim 4 is characterized in that,

Said whole priority=media priority * (total bandwidth of having lent/loanable bandwidth+1).

6. method as claimed in claim 3 is characterized in that,

Said degradation object allows the Media Stream of the session of QOS degradation for being registered in the degradation record;

The concrete grammar of said selection degradation object is:

Said PD-FE judges that initiating that said initializing resource requesting users had all are recorded in the session in the degradation record; Whether exist whole priority to be lower than said session of waiting to admit session; If exist, then the whole priority of initiating said initializing resource requesting users is lower than and saidly waits to admit the Media Stream of one or more sessions of session to demote by whole priority order from low to high.

7. method as claimed in claim 6 is characterized in that,

After the whole priority of initiating said initializing resource requesting users is lower than the said Media Stream of waiting to admit one or more sessions of session and demotes; If available resources still can not satisfy said resource requirement of waiting to admit session, then the whole priority in the degradation record of being recorded in that belongs to other users is lower than and saidly waits to admit the Media Stream of one or more sessions of session to demote.

8. method as claimed in claim 6 is characterized in that,

The bandwidth that maximum bandwidth that the transmission user identifier of recording conversation, resource control Session ID, whole priority, QoS-Downgradable parameter, stream numbering, Media Stream allow to lend in the said degradation record and Media Stream have been lent;

When setting up session, record allows the session of degradation in said degradation record; And after to session degradation, revise the whole priority of the session in the session respective entries of having demoted and describe with Media Stream, write down the historical operation that session is carried out.

9. the upgrade control method of a service quality is characterized in that,

After session carried out service quality QoS degradation, increase if PD-FE is known available resources, said PD-FE inquiry degradation record needs the session of upgrading in the session of therefrom selecting to have demoted; Said PD-FE judges said session according to session QoS-Downgradable parameter in the said degradation record, and whether needs are upgraded, and according to the whole priority of session in the said degradation record, according to order from high to low the Media Stream of session are upgraded; The priority of the one or more definite session in the loanable bandwidth of Media Stream that said whole priority is comprised for the total bandwidth of having lent according to media priority, Media Stream that session comprised and session; Whether the session of said QoS-Downgradable parameter identification allows the QoS degradation, and value comprises: do not allow the QoS degradation, allow the QoS degradation and do not need subsequent upgrade and allow the QoS degradation and need subsequent upgrade; The acquiescence value is for allowing the QoS degradation and not needing subsequent upgrade.

10. method as claimed in claim 9 is characterized in that,

Said PD-FE also judges the total resources whether available resources lend greater than session to be upgraded before the Media Stream upgrading of carrying out session, if greater than, then give back all resources of lending from session to be upgraded; Otherwise, with the said session to be upgraded of available resources complete restitution.

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