WRFD-141102 RNC User Plane and Control Plane Static Sharing (New/Basic)

Impacted Features

4.3 WRFD-141102 RNC User Plane and Control Plane Static Sharing (New/Basic)

4.3.1 Description

The EGPUa boards in a BSC6910 form two resource pools: the UP pool for processing UP data and the CP pool for processing CP data. Operators can set the ratio of resources allocated to process UP data and that to process CP data (referred to as the UP/CP ratio in this document) based on the traffic model. For example, when the CP central processing unit (CPU) usage is above a specified threshold, a certain amount of resources in the UP pool are reallocated to the CP. Figure 4-1 shows the resource reallocation between the CP and UP.

4-5 Figure 4-1 Resource reallocation between the CP and UP

This feature reduces the operator's purchasing and maintenance costs because fewer board types are needed. It also improves the hardware usage because operators can adjust the UP/CP ratio based on the traffic model. However, ongoing services on the adjusted processing units are interrupted during the adjustment.

4.3.2 Capacity and Performance

System Capacity

This feature improves system capacity in the following ways:

 If CP resources are insufficient and UP resources are sufficient, a certain amount of hardware resources in the UP pool are reallocated to the CP. This increases BHCA capacity.

 If UP resources are insufficient and CP resources are sufficient, a certain amount of hardware resources in the CP pool are reallocated to the UP.

Network Performance

This feature balances the load between the CP and UP to prevent critical CP/UP overload. This

improves system reliability. When the UP/CP ratio is changed, ongoing processes are stopped and then new processes are started. Therefore, this feature has the following impact on ongoing services during resource reallocation between the CP and UP:

 NodeBs, cells, transmission links, and signaling links controlled by the adjusted process are redistributed. This causes some NodeBs to go out of service for about 20 seconds.

 Services allocated to the adjusted process are interrupted, increasing the call drop rate. PS services are reestablished after being interrupted.

 If the UP/CP ratio is set inappropriately, a large number of NodeBs and cells may not be allocated suitable CP and UP resources. This results in network disconnection and alarm reporting. To prevent this problem, operators must set the ratio to a proper value based on the board specifications and the number of configured boards.

Setting the UP/CP ratio may have severe negative effects. Therefore, this operation should be

performed during off-peak hours. When adjusting the ratio, do not drastically change the settings. Make moderate changes to avoid impacting ongoing services.

4.3.3 Impact on NEs

This feature is implemented on the RNC.

4-6

4.3.4 Impact on Hardware

Only the BSC6910 supports this feature.

4.3.5 Inter-NE Interface

No impact.

4.3.6 Operation and Maintenance

License

This feature is not under license control.

Configuration Management

The amount of available CP and UP resources and the effect of ratio adjustment change when both of the following are true:

 Before the ratio adjustment, a board is not installed or a board is faulty.

 After the ratio adjustment, a board is added or the faulty board recovers or is replaced.

Therefore, resolve any related problems before adjusting the ratio. After adding or replacing a board, check the resource usage of the CP and UP pools and determine whether to readjust the ratio.

Table 4-3 describes the new RNC MML commands related to this feature.

Table 4-3 New RNC MML commands related to this feature Change Type MML Command Description

New SET UCPUPFLEXCFG Use this command to set the following parameters related to the WRFD-141102 RNC User Plane and Control Plane Sharing and WRFD-141201 RNC User Plane and Control Plane Dynamic Sharing features:

 FlexCfgMode

 FlexCfgPeriod

 Flex Cfg Act Time

New LST UCPUPFLEXCFG Use this command to query the parameters related to the WRFD-141102 RNC User Plane and Control Plane Sharing and WRFD-141201 RNC User Plane and Control Plane Dynamic Sharing features.

New DSP

UCPUPFLEXCFG

Use this command to query dynamic RNC information about the WRFD-141102 RNC User Plane and Control Plane Sharing and WRFD-141201 RNC User Plane and Control Plane Dynamic Sharing features.

New DSP URSVCAP Use this command to query the number of NodeBs and cells that can be added.

Table 4-4 describes the new RNC parameters related to ALM-22015 Resource Overload on the Control Plane.

4-7 Table 4-4 New RNC parameters related to ALM-22015 Resource Overload on the Control Plane

Change Type Parameter ID MML Command Description

New CtrlPlnCPUAlmTh d

SET UALMTHD Average CP CPU usage threshold at which ALM-22015 Resource Overload on the Control Plane is reported

New CtrlPlnCPUClrTh d

SET UALMTHD Average CP CPU usage threshold at which ALM-22015 Resource Overload on the Control Plane is cleared

Performance Management

No new counters related to this feature have been added. The DSP UCPUPFLEXCFG command has been added to monitor the CP and UP CPU usages before and after resource reallocation.

Fault Management

Two alarms related to transmission resource pools have been added on the RNC side:

 ALM-22015 Resource Overload on the Control Plane

 ALM- 22016 Restricted Flexible Deployment

4.3.7 Impact on Other Features

No impact.

4.4 WRFD-141103 Automatic NodeB and Cell Allocation in the

In document RAN15.0 Network Impact Report Draft A(PDF)-EN.pdf (Page 40-43)