CN1486096A

CN1486096A - Load control method for Iu interface supporting Iu Flex technique

Info

Publication number: CN1486096A
Application number: CNA021317828A
Authority: CN
Inventors: 赵红霞
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2002-09-23
Filing date: 2002-09-23
Publication date: 2004-03-31
Anticipated expiration: 2022-09-23
Also published as: CN1223215C

Abstract

The invention is a load control method for Iu interface in UMTS network, the method includes: RNC samples the received load quantity, and calculates the loadaverage. Then sends instruction load control message to CN; RNC computes the StepNumi which is needed to be reduced of each CN joint instruction, and calculates the sum of each CN joint instruction flow, and the difference value delta StepNum with Total Steps, it the delta StepNum is zero, the step number of each CN is StepNumi; if it isn't zero, it sends CN with the biggest flow to RNC, hypothesizes it is 'j' CN, the step number of the CN is the sum of StepNumj and deltaStepNum; Finally, RNC informs each CN to start instruction load control, and provide the StepNumi which needs to be adjusted.

Description

Support the Iu interface load control method of IuFlex technology

Technical field

The present invention relates to UMTS (Universal Mobile Telecommunication Systems, universal mobile telecommunications system) MBMS of network (Multimedia Broadcast/Multicast Service, multimedia broadcast/multi broadcast business) business, relate in particular in the UMTS network that adopts the IuFlex technology, carry out MBMS control to the load of Iu interface when professional.

Background technology

Therefore how in recent years, universal day by day for the application of UMTS network, load is controlled and is placed on the research and development schedule to the RNC in this network (Radio Network Controller, radio network controller).

Fig. 1 illustrates in the UMTS network, the RANAP of the Iu interface load between RNC and the CN (Core Network, core net) (Radio Access network Aplication Protocal, wireless access application protocol) rules.According to present industry rules, owing to load in the time of to issue signaling message to subscriber equipment too greatly, will send OVERLOAD (overload) message to CN as RNC.After CN receives message, the load of the Iu interface of RNC is controlled by following steps:

1. as if the timer T of CN at it _IgOCIn the absence of operation, receive the OVERLOAD message from RNC, the traffic carrying capacity that then will be handed down to this RNC reduces a step.

As optional, CN can indicate the step number that reduces in OVERLOAD message.Meanwhile, the timer T among the startup CN _IgOCAnd T _InTC

2. at timer T _IgORun duration, CN are ignored all OVERLOAD message from RNC;

3.CN reduce to be handed down to the traffic carrying capacity of RNC step by step, up to executing final step;

4. if timer T _InTCCross after date, do not receive the new OVERLOAD message from RNC, then traffic carrying capacity will increase step by step, and will be normal if the traffic carrying capacity of the Iu interface bearing of RNC is not recovered, and then should restart timer T _InTC

In order in the network that adopts the IuFlex technology, to realize above-mentioned industry rules, the method for the Iu interface bearing of two kinds of control RNC is arranged at present.

First method, as shown in Figure 2, when carrying out the MBMS business, if several CN are handed down to the traffic carrying capacity summation overload of a RNC, then in these several CN, send overload message to a CN of its traffic carrying capacity maximum that issues by this RNC, this CN controls its MBMS service message that is handed down to this RNC, thereby reaches the purpose of control Iu interface load.

There is a significant disadvantages in this method, promptly is merely able to the CN traffic carrying capacity from the traffic carrying capacity maximum of that transmission is controlled.When the traffic carrying capacity that therefore only suitable some CN issue to RNC differs bigger, the traffic carrying capacity that is handed down to RNC is controlled.But, when the traffic carrying capacity that issues to RNC as each CN is more or less the same, only the CN of issuing service amount maximum is wherein controlled difficult load with RNC and be reduced to normal level because that cause this RNC traffic overload is the CN of oriented its issuing service data of institute.

Second method, when RNC transships, with overload message send to the CN of oriented its issuing service data, thereby make each CN all reduce the traffic carrying capacity that RNC is issued.As shown in Figure 3.

Also there is significant disadvantages in this mode, promptly causes the traffic carrying capacity transition to the Iu interface to reduce easily, causes the wasting of resources.Give one example below.

As shown in Figure 3, there are 4 CN to insert, when its finds to have transshipped itself if RNC is current, according to the industry rules, this RNC will calculate the total business volume that sends to it need reduce for 5 steps, sent overload message to 4 CN respectively immediately, and informed that needing that the current traffic carrying capacity that sends to it is reduced 5 goes on foot.Then, these 4 CN reduced for 5 steps with the traffic carrying capacity that will send to RNC simultaneously.Because 4 CN have reduced to be handed down to the traffic carrying capacity of RNC, the very fast reduction of the total traffic that all these RNC receive is got off.

Produced a problem this moment.According to the industry rules, when having only the step number that reduces when each CN downlink traffic to surpass the step number that RNC oneself provides, just can restart to increase the traffic carrying capacity that they are handed down to RNC.Before 4 CN begin to increase the traffic carrying capacity that issues, even the service traffics of RNC have been recovered normally, if but CN has not also reduced by 5 steps to the downlink business flow, and then CN continues to reduce flow, thereby may cause transition to reduce the downlink business flow, waste resource.

Summary of the invention

The objective of the invention is to the shortcoming that exists in the method in the front existing two, a kind of new Iu interface load control method is proposed, this method promptly can avoid being difficult for reducing owing to the issuing service flow of only controlling a CN in the first method problem of service traffics, has also overcome in the second method owing to transition reduces the shortcoming that the downlink business flow is wasted resource.

A kind of Iu interface load control method provided by the invention comprises following steps: step 1: when the load of RNC had surpassed the overload parameter L oadMax that sets in advance, RNC started timer Tobserved, entered the observation stage of service traffics load control; Step 2:RNC samples to its load capacity that receives during timer Tobserved regularly; Step 3:RNC calculates average load LoadAverage according to sampled result; Step 4:RNC judges that whether average load LoadAverage is more than or equal to overload parameter L oadMax, if then RNC sends signaling load control messages to CN, and the required step number TotalStep of calculation control load; Step 5:RNC statistics is at Tobserved signaling traffic Vi from each CN in the time, and wherein i represents i CN; Step 6:RNC calculates the step number StepNumi that each CN node signaling traffic should reduce, and calculate the step number StepNumi sum of described each CN and the difference DELTA StepNum of the described step number TotalStep in the step 4, if described difference DELTA StepNum is zero, then the step number of each CN is described StepNumi; If described difference DELTA StepNum is non-vanishing, then select to issue the CN of signaling traffic maximum to RNC, then the step number of this CN is described StepNumi and Δ StepNum sum; Step 7:RNC notifies each CN to begin signaling load control, and the step number StepNumi that needs adjustment is provided.

In the present invention, computational load is controlled required step number TotalStep=(LoadAverage-LoadMax)/(100%-LoadMax) * 16 in such a way, and result of calculation is rounded up.In addition, each CN signaling traffic step number StepNumi that should reduce calculates in such a way:

StepNumi＝(Vi/∑Vi*TotalStep ———(a)

StepNumi rounds downwards, and its Vi is the signaling traffic that flows to this RNC at Tobserved in the time.

In addition, if the same maximum of the flow of 2 above CN is arranged in the step 6, then RNC selects one arbitrarily.

Iu interface load control method by the present invention's proposition, not only avoided being difficult for reducing owing to the issuing service flow of only controlling a CN in the above-mentioned first method problem of service traffics, also overcome in the second method owing to transition reduces the shortcoming that the downlink business flow is wasted resource.

Description of drawings

Fig. 1 is the industry rules schematic diagram of Iu interface load control framework;

Fig. 2 is a kind of Iu interface load control method schematic diagram of the prior art;

Fig. 3 is an another kind of Iu interface load control method schematic diagram of the prior art;

Fig. 4 is the Iu interface load control method schematic diagram that the present invention proposes.

Specific embodiment

Specifically describe in the network of supporting the IuFlex technology control method of the Iu interface load between RNC and the CN below.

As shown in Figure 4, CN1, CN2, CN3 and CN4 are respectively to RNC issuing service data.When RNC finds oneself overload, start a timer, at this timer run duration, the service traffics from each CN are monitored.

After regularly finishing, RNC proportionally controls the service traffics that they issue to RNC according to the size of each CN node current business flow.

Detailed process is as follows:

Preestablishing the heap(ed) capacity that RNC can carry is 100%, and in NRC configuration RNC overload parameter L oadMax, this numeral be one less than 100% numerical value.

Step 1: when in some moment, when the load of RNC had surpassed above-mentioned LoadMax, RNC started timer Tobserved, entered the observation stage of service traffics load control;

Step 2: during timer Tobserved regularly, RNC sampled to the load capacity that it receives, and the number of setting sampled point is Ns.Then the time interval of the sampling of RNC is Tobserved/Ns.

Step 3: after timer Tobserved regularly finishes, the average load LoadAverage that RNC calculates in the observation period according to the sample value that collects.

Whether step 4:RNC judges LoadAverage more than or equal to LoadMax, if then RNC sends signaling load control messages to CN.Specifically, RNC calculates the step number TotalStep that needs control according to following computational methods:

TotalStep＝(LoadAverage-LoadMax)/(100％-LoadMax)*16

Result of calculation is rounded up, and for example the result is 15.1, then gets 16.

Need to prove, because 3GPP has stipulated that maximum adjustment step number is 16, so in this programme with (100%-LoadMax) as the load capacity that 16 step institutes can adjust, promptly can only adjust (100%-LoadMax) at most, be not need load to control less than normal load LoadMax.So the inventor thinks that it is rational adopting above formula.

Step 5:RNC is according to the sampled result of front, and statistics is from the signaling traffic Vi of each CN, and wherein i represents i CN.

Step 6:RNC calculates the step number StepNumi that each CN node signaling traffic should reduce by the following method:

(1)StepNumi＝(Vi/∑Vi)*TotalStep ———(a)

StepNumi rounds downwards

(2) calculate the difference of StepNumi sum and TotalStep according to following formula:

ΔStepNum＝TotalStep-∑StepNumi ———(b)

(3) judge whether Δ StepNum is non-vanishing,

If be zero, then the step number of each CN is the StepNumi that formula (a) calculates;

If non-vanishing, then select the CN of flow maximum, then the step number of this CN is to calculate StepNumi and Δ StepNum sum of gained in (a).

If the flow more than two CN is equally big, then select one arbitrarily.

The downward round numbers of StepNumi need to prove, owing to just can guarantee that when the flow of certain CN is minimum RNC does not send out Flow Control message to it.

The method of calculating StepNumi is except (1), the cooperation that has also added (2) (3) steps, this is based on following consideration: if only adopt (1), under certain extreme case, such as 10 shared ratios of CN respectively is 10%, and TotalStep=5, only calculate StepNumi in this case according to top (1), the StepNum of each CN is zero, the flow of each CN all one the step do not reduce, then can't control, for fear of above situation the downlink traffic of RNC, the processing that has added (2) (3) steps is to avoid this situation.

Step 7:RNC sends OVERLOAD message by RANAP (wireless access network application protocol) signaling to each CN, notifies these CN to begin signaling load control, and indicate the step number StepNumi that needs adjustment in message.In the present embodiment, the step number that reduces of CN1, CN2, CN3 and CN4 is respectively 3,0,1,1.When step number is zero, needn't send OVERLOAD message.

Claims

1. Iu interface load control method is characterized in that comprising following steps:

Step 1: when the load of radio network controller had surpassed the overload parameter L oadMax that sets in advance, radio network controller started timer Tobserved, entered the observation stage of service traffics load control;

Step 2: radio network controller is sampled to its load capacity that receives during timer Tobserved regularly;

Step 3: radio network controller calculates average load LoadAverage according to sampled result;

Step 4: radio network controller judges that whether average load LoadAverage is more than or equal to overload parameter L oadMax, if then radio network controller sends signaling load control messages to core net, and the required step number TotalStep of calculation control load;

Step 5: from the signaling traffic Vi of each core net, wherein i represents i core net to the radio network controller statistics in the time of timer Tobserved;

Step 6: radio network controller calculates the step number StepNumi that each core net node signaling traffic should reduce, and calculate the step number StepNumi sum of described each core net and the difference DELTA StepNum of the described step number TotalStep in the step 4, if described difference DELTA StepNum is zero, then the step number of each core net is described StepNumi; If described difference DELTA StepNum is non-vanishing, then select to issue the core net of signaling traffic maximum to radio network controller, then the step number of this core net is its StepNumi and Δ StepNum sum;

Step 7: radio network controller notifies each core net to begin signaling load control, and the step number StepNumi that provides each core net to adjust.

2. Iu interface load control method as claimed in claim 1 is characterized in that required step number TotalStep=(LoadAverage-LoadMax)/(100%-LoadMax) * 16 of computational load control in such a way, and result of calculation is rounded up.

3. Iu interface load control method as claimed in claim 1 is characterized in that, the step number StepNumi that described each core network signalling flow should reduce calculates in such a way:

StepNumi=(Vi/ ∑ Vi) * TotalStep---(a) and, StepNumi rounds downwards.

4. Iu interface load control method as claimed in claim 1 is characterized in that, if the same maximum of the flow of 2 above core net is arranged in the step 6, then radio network controller is selected one arbitrarily.