The present disclosure generally relates to wireless communication networks. In particular, a technique for controlling reporting of network events by one or more network functions, NF, of a wireless communication network is disclosed. The technique may be implemented in the form of a method, a computer program product, an apparatus, and a system.
Network management is an important feature of modern wireless communication networks. Network management decisions require a continuous collection and analysis of a plethora of network events occurring locally within the managed network and reported by the network to a network management domain. Such network events are typically reported on a subscriber level to achieve a sufficiently high resolution for network analysis.
Traditional event collection is based on passive probing of, or pre-configured event reporting by, different network functions within possibly different domains of a wireless communication network. While the volume of reported network events is already significant in wireless communication networks of the current 4th Generation (4G), the event reporting volume is expected to drastically increase with the deployment of 5th Generation (5G) networks (also called New Radio, NR, networks). This increase is partly due to much higher numbers of terminal devices of various kinds, including Internet of Things (IoT) devices, and partly the result of new service types that will become available in 5G networks.
As an example, it is expected that event collection by user plane probing in a 5G network will per core network site easily result in several terabit of user plane traffic that needs to be processed and evaluated in real time. A similar situation will arise in the radio access network domain as a result of the increasing numbers of devices and cells. Evidently, significant server capacities, and also a lot of electric power, will be consumed in this regard.
Attempts have been made to reduce the reported volume of network events. For example, it has been suggested to apply random event sampling techniques to reduce the amount of data that needs to be analyzed for network management purposes. However, such random sampling of network events has been found to reduce the efficiency of network anomaly detection as it cannot be ensured that, for example, problematic communication sessions are not “filtered out” in view of the applied randomness.
There is a need for efficiently controlling reporting of network events in a wireless communication system.
According to a first aspect, a method of controlling reporting of network events by one or more network functions, NF, of a wireless communication network is provided. The method comprises receiving, from at least one network analytics component, a net-work analytics request indicative of at least one event reporting requirement of the at least one network analytics component, and receiving, from at least one NF, one or multiple NF reports indicative of at least one of an event reporting capability, a load and a capacity of the at least one NF. The method further comprises generating an event reporting request based on the at least one event reporting requirement and at least one of the event reporting capability, the load, and the capacity of the at least one NF, and sending the event reporting request to the at least one NF so as to control event reporting by that at least one NF.
As understood herein, the term “multiple” generally denotes a number of two or more.
A particular NF and/or a network particular analytics component may be a software entity (e.g., implemented using cloud computing resources), a stand-alone hardware entity (e.g., in the form a network node), or a combination thereof. A particular NF may belong to a cellular wireless communication network, for example of the 4th or 5th Generation. A particular NF may belong to a radio access network (RAN) domain or a core network (CN) domain of the cellular wireless communication network. A particular network analytics component may belong to a network management (NM) domain of the wireless communication network.
The method may comprise receiving multiple network analytics requests that are collectively indicative of multiple event reporting requirements. The method may further comprise merging the multiple event reporting requirements into an overall event reporting requirement for the at least one NF. In this case, the event reporting request sent to the at least one NF can be based on the overall event reporting requirement. As an example, the event reporting request may include the overall event reporting requirement (e.g., as a numerical or non-numerical parameter) or a parameter derived therefrom.
The network analytics requests may be received from one and the same network analytics components or from multiple different analytics components. As such, at least two of the multiple event reporting requirements may be received from different network analytics components (potentially operated by different users within the NM domain of one network operator or by different network operators).
At least two of the multiple event reporting requirements may comprise a numerical value. In such a case, merging the multiple event reporting requirements may comprises deriving, from the (possibly different) numerical values comprised in the at least two of the multiple event reporting requirements, an overall numerical value to be comprised by the overall reporting requirement. The overall numerical value may, for example, be the least or greatest common multiple of the numerical values, a minimum or maximum of the numerical values, and so on.
Multiple NF reports may be received from multiple NFs. In such a case, the event reporting request for a particular one of the multiple NFs can be individualized based on at least one of the event reporting capability, the load and the capacity of that particular NF. As an example, in case the load or capacity relates to one or more of general processing, monitoring or storage resources of a particular NF, the event reporting request may be generated such that a currently high processing load or a currently low monitoring capacity of that particular NF is not (or not significantly) worsened. This approach may result in the event reporting requirement not (or not fully) being satisfied by that particular NF.
The event reporting request may be indicative of at least one of an event sampling rate to be applied by the at least one NF, an event filter setting to be applied by the at least one NF, and one or more key performance indicators, KPIs, for which event reporting is to be performed by the at least one NF.
If the event reporting requirement is indicative of at least one KPI and an associated precision requirement, the method may comprise calculating the event sampling rate based on the precision requirement, wherein the event reporting request is indicative of at least the calculated event sampling rate and the at least one KPI. If the event reporting request is indicative of at least the event sampling rate, the method may comprise sending, to the at least one network analytics component, a message indicative of the event sampling rate or a parameter derived therefrom.
The event filter setting may be indicative of one or more of a set of (i) one or more network subscribers to be covered by NF event reporting, (ii) a wireless device class or type to be covered by NF event reporting, and (iii) a geographic area to be covered by NF event reporting. The network subscribers to be covered by NF event reporting on a subscriber level may be identified in various ways, for example by a set of one or more subscription permanent identifiers (SUPIs), a set of one or more international mobile subscriber identities (IMSIs), a set of one or more cell identifiers, a set of one or more radio session identifiers, and so on.
The NF report from the at least one NF may be indicative of an NF event reporting capability in terms of an event filter supported by the at least one NF. In such a case, generating the event reporting request for the at least one NF may comprise processing the event reporting requirement to result in an event filter setting compatible with the event filter supported by the at least one NF. The event filters may relate to identifiers used in the network. As an example, in case a given NF only supports radio session identifiers for event filtering on a subscriber level, and in case the event reporting requirement is indicative of a cell identifier or a set of SUPIs or IMSIs, the latter may be converted to radio session identifiers (as event filter settings) when generating the event reporting requirement that is to be transmitted to the NF.
If multiple NF reports are received from multiple NFs, the multiple reports may be indicative of different event filters supported by different NFs. In such scenario, generating the event reporting requests for the NFs may comprises processing the network reporting requirements to result in coherent event filter settings compatible with the different events filters supported by the different NFs. In the above example, a first NF only supporting radio session identifiers may thus receive a set of radio session identifiers, whereas a second NF only supporting SUPIs may receive a set of SUPIs that is coherent with the set of radio session identifiers (e.g., in terms of the set of subscribers to be covered).
The processing of the network reporting requirements may, for example, target at controlling event reporting by the multiple NFs such that the multiple NFs are configured to report events pertaining to a particular communication session (e.g., an end-to-end session between different user terminals or a user terminal and an application server) despite their different event filters. The correspondingly reported events may then easily be correlated in the NW domain (e.g., by the analytics components) by applying a mapping reflecting the different event filters (e.g., a mapping between different identifier types associated with the same communication session). Such a mapping may previously have been communicated to the event reporting control component to facilitate the processing the network reporting requirements to result the coherent event filter settings.
When multiple NF reports are received from a particular NF, a first NF report of the multiple NF reports may be indicative of the event reporting capability of that particular NF. Moreover, a second NF report of the multiple NF reports may be indicative of at least one of the load and the capacity of that particular NF. For example, when sending an NF capability request to the particular NF, the first NF report may be received responsive to the NF capability request. Sending the NF capability request may be triggered by receipt of the network analytics request. As a further example, the second NF report may be received repeatedly (e.g., periodically) after the event reporting request has been sent to the particular NF. The second NF report may further be indicative of current event reporting settings (e.g., a current event filter setting or a current sampling rate) of the particular NF.
The method may in some scenarios comprise receiving, from the at least one network analytics component, analytics information derived from the NF event reporting and generating a further event reporting request based on at least the analytics information. The method may further comprise sending the further event reporting request to the at least one NF so as to modify event reporting by that at least one NF. The analytics information may be indicative of at least one of (i) a network anomaly (e.g., a severely degraded service quality for a dedicated subscriber or set of subscribers), (ii) a number of events reported by a particular NF, optionally for a particular KPI, and (iii) a mapping of identifiers used in different network domains (e.g., SUPI to radio session identifier, or vice versa).
The further event reporting request may be generated also based on at least one of the event reporting capability, the load and the capacity of the at least one NF. Additionally, or as an alternative, the further event reporting request may control a modification of at least one of a currently applied event sampling rate, a currently monitored KPI set, a currently reporting set of NFs, and a currently applied event filter setting.
The one or more NFs may be implemented using cloud computing resources. In such a case, an amount of cloud computing resources allocated to a particular NF may be dependent on the event reporting request sent to that particular NF. If, for example, the requested event reporting results in an increased load or a reduced capacity of the particular NF, more cloud computing resources may be allocated by a cloud orchestrator to that particular NF.
The method can comprise determining if the network analytics request from the at least one network analytics component can be fulfilled in view of at least one of the event reporting capability, the load and the capacity of the at least one NF. The method may further comprise sending, to the at least network analytics component, a network analytics response message indicative of a result of the determination (e.g., indicative of the fact that the network analytics request cannot, or not fully, be fulfilled).
In some implementations, the method is performed by an event reporting control component having a first interface towards the at least one network analytics component and a second interface towards the at least one NF. The event reporting control component can be co-located with the at least one network analytics component in an NM domain. Optionally, the NM domain further comprises an event collection component having a third interface towards the at least one network analytics component and a fourth interface towards the at least one NF for receiving event reports from the at least one NF.
Multiple NFs may be provided in different network domains of the wireless communication network. The different network domains may comprise at least an RAN domain and a CN domain. In such a case, multiple NF reports may be received from, and multiple event reporting requests may be sent to, NFs provided in the different network domains.
Also provided is a computer program product comprising program code portions for performing the steps of any of the methods presented herein when the computer program product is executed by a processor or set of processors. The computer program product may be stored on a computer-readable recording medium.
Further provided is an apparatus for controlling reporting of network events by one or more NFs of a wireless communication network. The apparatus is configured to receive, from at least one network analytics component, a network analytics request indicative of at least one event reporting requirement of the at least one network analytics component and, to receive, from at least one NF, one or multiple NF reports indicative of at least one of an event reporting capability, a load and a capacity of the at least one NF. The apparatus is also configured to generate an event reporting request based on the at least one event reporting requirement and at least one of the event reporting capability, the load and the capacity of the at least one NF, and to send the event reporting request to the at least one NF so as to control event reporting by that at least one NF.
The apparatus may be configured to perform any of the method steps presented herein.
Still further, another apparatus for controlling reporting of network events by one or more NFs of a wireless communication network is presented. The other apparatus comprises a processor and a memory coupled to the processor, the memory comprising instructions executable by the processor whereby the apparatus is operative to perform a method presented herein.
Also provided is an NM system comprising the apparatus presented herein. The NM system further comprises the at least one network analytics component.
Further aspects, details and advantages of the present disclosure will become apparent from the detailed description of exemplary embodiments below and from the drawings, wherein:
In the following description, for purposes of explanation and not limitation, specific details are set forth in order to provide a thorough understanding of the present disclosure. It will be apparent to one skilled in the art that the present disclosure may be practiced in other embodiments that depart from these specific details.
While, for example, some embodiments of the following description focus on an exemplary core network configuration in accordance with specific 4G and 5G specifications, the present disclosure is not limited in this regard. The present disclosure could also be implemented in other cellular or non-cellular wireless communication networks.
Those skilled in the art will further appreciate that the steps, services and functions explained herein may be implemented using individual hardware circuits, using software functioning in conjunction with a programmed microprocessor or general purpose computer, using one or more application specific integrated circuits (ASICs) and/or using one or more digital signal processors (DSP). It will also be appreciated that when the present disclosure is described in terms of a method, it may also be embodied in one or more processors and one or more memories coupled to the one or more processors, wherein the one or more memories store one or more computer programs that perform the steps, services and functions disclosed herein when executed by one or more processors.
In the following description of exemplary embodiments, the same reference numerals denote the same or similar components.
The embodiments that follow generally relate to reporting of network events, to controlling the event reporting and to analyzing the reported events. As understood herein, network events are to be construed broadly. Network events generally characterize what is happening in a communication network, such as session initiation or termination, the status of an ongoing session, transmission of a certain amount of data and so on. So called key performance indicators, or KPIs, (usually numeric) can be reported as events as such or as attributes of one or more events, such as session initiation time, ratio of unsuccessful session initiations, the amount of transmitted bytes over a given amount of time and so on. An event can be reported when it is locally detected by an NF or in response to probing. The events can be standardized (e.g., 4G or 5G) signalling events or vendor-specific events (of, e.g., a network node acting as NF). Event probing may be performed to capture the events at a network interface or to capture user plane traffic, sample it and generate user plane traffic metrics that are to be reported as one or more events. KPIs can be calculated from or attributed to one or multiple events.
As an example, a handover failure can be reported in an event. Exemplary KPIs calculated from this or these events either locally in the communication network or centrally in an NM domain are a number of handover failures or a ratio of the handover failures and the total handovers in a time period. As another example, a user plane probe may report a throughput event every 5 s in a dedicated event report. An average throughput KPI can be calculated locally or centrally as the average of these throughputs for 1 min, and a maximum throughput KPI can be calculated locally or centrally as the maximum of the reported throughputs in 1 min.
The CN domain 110 and the RAN domain 120 each comprises a large number of NFs 140. A particular NF 140 may be a software entity (e.g., implemented using cloud computing resources), a stand-alone hardware entity (e.g., in the form a network node), or a combination thereof. When using cloud computing resources, an amount of cloud computing resources allocated to a particular NF 140 may be dependent on the event reporting load on that particular NF. If, for example, the requested event reporting load results in an increased load or a reduced capacity of the particular NF 140, more cloud computing resources may be allocated by a cloud orchestrator to that particular NF 140. Each NF 140 comprises a bi-directional communication link to the NM domain 130 for receiving event reporting requests from the NM domain 130 and sending event reports to the NM domain 130.
The exemplary NFs 140 of
As illustrated in
The analytics components 134 are each configured to send network analytics requests to the event reporting controller 136 that receives these requests via a dedicated interface 136A. Moreover, the event reporting controller 136 comprises a further dedicated interface 136B towards the NFs 140 to receive NF reports from the NFs and to send event reporting requests towards the NFs. The interfaces 136A, 136B can each be configured as a software interface, a hardware interface or a combination thereof. As will be explained in greater detail below, the event reporting controller 136 may be configured to generate the event reporting requests based on information contained in the NF reports as received from the NFs 140 and based on information contained in the network analytics requests as received from the analytics components 134.
The analytics components 134 are not only configured to generate the network analytics requests for the event reporting controller 136, but also to analyse the events collected from the NFs 140 by the event collecting component 132. To this end, the event collecting component 132 has a dedicated interface 132A that provides the analytics components 134 with access to an event collection database hosted by the event collecting component 132. The event collection component 132 has a further dedicated interface 132B towards the NFs 140 to receive event reports from the NFs 140. The event collection component 132 is configured to store the events reported by the NFs 140 in its event collection database. The interfaces 136A, 136B can each be configured as a software interface, a hardware interface or a combination thereof.
The analytics components 134 may be configured as customer experience management (CEM) systems or subscriber analytics systems (such as Ericsson Experts Analytics, EEA, systems). The analytics systems 134 may be comprised by one or more of network operation centres (NOCs), service operation centres (SOC) and network optimization engineering (NOE) systems. In some implementations, the analytics systems 134 are configured to monitor and analyse service quality and network quality on a subscriber level. The analytics systems 134 may be software entities (e.g., implemented using cloud computing resources), (e.g., stand-alone) hardware entities, or combinations thereof.
In the following, an apparatus embodiment of the event reporting controller 136 of
In the apparatus embodiment illustrated in
The event reporting controller 136 further comprises an input interface 206 and an output interface 208. The two interfaces 206, 208 are configured for communication with the analytics components 134 on the one hand and the NFs 140 on the other hand. The interfaces 206, 208 may be configured to implement the interfaces 136A, 136B described above with reference to
Now referring to the flow diagram 300 of
Operation of the event reporting controller 136 further comprises a step 304 of receiving, from at least one of the NFs 140, one or multiple NF reports indicative of at least one of an event reporting capability, a load and a capacity of the at least one NF 140. The one or more NF reports will be received via the input interface 206 (when implementing the interface 136B of
Steps 302 and 304 may be performed in any order, and also concurrently. In some scenarios, receipt of the network analytics request by the event reporting controller 136 triggers sending a dedicated request by the event reporting controller 136 towards one or more of the NFs 140, which in turn triggers the one or more NFs 140 so send their NF report(s) to the event reporting controller 136.
The method further comprises, in step 306, generating, by the processor 202 of the event reporting controller 136, an event reporting request based on the at least one event reporting requirement and at least one of the event reporting capability, the load, and the capacity of the at least one NF. Still further, the method comprises, in step 308, sending the event reporting request to the at least one NF 140 so as to control event reporting by that at least one NF 140 towards the NM domain 130 (i.e., towards the event collecting component 132). The event reporting request will be sent by the event reporting controller 136 via the output interface 208 (when implementing interface 136B of
The event reporting request will be indicative of one more of an event sampling rate and an event filter setting to be applied by the NF 140. Additionally, or as an alternative, the event reporting request may indicate one or more KPIs for which event reporting is to be performed by the NF 140. In some cases, the event filter setting may define a set of subscribers to be monitored for reporting purposes. In such a case, the event filter setting may comprise a white list of the subscriber to be monitored or a black list of subscribers not to be monitored. The corresponding list may be defined using SUPIs, IMSIs or any other identifier type. The list may, for example, include or exclude certain subscribers based on consent or subscription type.
The method embodiment of
In step 1a, one of the network analytics components 134 of
Receipt of the network analytics request by the event reporting controller 136 (see step 302 of
In step 2b, each of the one or more NFs 140 returns a dedicate NF report indicative of the NF's 140 event reporting capability to the event reporting controller 136 (see step 304 in
Based on the information received in the NF report(s), the event reporting controller 136 determines if the NF(s) 140 can fulfil, or support, the event reporting requirement(s) as signalled by the at least one network analytics component 134 in step 1a. The event reporting controller 136 then, in step 1b, returns a network analytics response message to the network analytics component 134. This message indicates whether or not fulfilment of the event reporting requirement(s) is feasible. As an example, support of certain UCs may be infeasible due to the required event type(s), event sampling rate(s) or event filter(s) not being supported by the required NF(s) 140.
The NF 140 may be pre-configured, or may be configured by the event reporting controller 136 in message 2a or in a dedicated configuration message, to regularly (e.g., periodically) send further NF reports indicative of one or both of the current NF processing load and the current NF event monitoring capacity to the event reporting controller 136 (see step 3 in
Occasionally, the network analytics component 134 may send analytics information to the event reporting controller 136, see step 4 in
While the loop illustrated in
An initial, or first, communication of the event reporting request (e.g., with, optionally default, settings of event filters and sampling rates) to the NFs 140 may have happened in step 7 upon a first iteration of the loop. During this first iteration, step 3 may report no sampling and no filters being applied (i.e., there is no data collection and associated event reporting); steps 4 and 6 may be void; and step 5 may determine default settings taking into account the requirements from step 1a and the load/capacity information from step 3. In such a scenario, step 7 may be the first communication of the settings to the NFs 140.
A later modification of reporting parameters in step 7 may include one or more of currently applied sampling rates, currently applied event filter settings, currently reporting set of NFs 140 (i.e., stopping or resuming event reporting by a particular NF 140), and currently monitored KPIs.
The event reporting controller 136 may further inform the analytics component 134 of the precision that currently is feasible for a given KPI subject to event reporting, see step 6. This KPI precision information may be derived by the event reporting controller 136 from the currently applied (or requested) event sampling rate of a given NF 140 or across a given set of NFs 140. In some variants, the analytics component 134 may have indicated, for example in step 1a, a precision requirement for a KPI (e.g., as part of a UC requirement) for which event reporting is to be performed. In such a case, the event reporting controller 136 may have calculated the required event sampling rate based on the precision requirement (with a higher precision requirement leading to a higher sampling rate). In case the event reporting controller 136 determines (e.g., from the information received in step 3 or in case of a lowering of the sampling rate in step 7) that the precision requirement, or any other UC requirement, can no longer be fulfilled, it will notify the analytics component 134 thereof in step 1c. The reason for such a notification may be that one or more of the NFs 140 have entered a state of high processing load with an associated low event monitoring capacity, that lead to an event sampling rate reduction in step 7.
Instead of, or in addition to, increasing the event sampling rate, the event filter settings may be modified to increase the event reporting precision (e.g., by extending a white list of subscribers to be monitored). Such increase(s) may be performed in case network anomalies are signalled by the analytics component 134 in step 4 to support root cause analysis in the NW domain 130. The increase(s) may specifically be performed for certain network sites (e.g., geographic areas such as cells), subscriber segments or device types affected by the network anomaly. Evidently, different sampling and filter settings may be chosen for different network sites. In some cases, the event reporting controller 136 may request the NFs 140 to perform random sampling (e.g., of randomly selected communication sessions). Optionally, the subscribers are divided into random segments (e.g., hash bins across SUPIs or IMSIs) for event reporting.
The loop illustrated in
In the following, various UC and a merging of UCs will be described with reference to the exemplary scenarios of
Based on the prevailing load information received in step 2b or step 3, the NFs 140 will get different sampling requests from the event reporting controller 136: heavily-loaded: 1% sampling, low-loaded: 100% sampling, and normal profile: sampling based on current load. As explained above, the load (step 3) and reported event record count (step 4) will be constantly monitored by the event reporting controller 136 and will be used to correct the filter configuration and an associated reporting (step 1c) in case UC1 requirements are not met. With current solutions, this correction needs to be done manually, resulting in high operational costs of the NM domain 130.
In case the event reporting controller 136 receives multiple network analytics requests in step 1a (from one multiple analytics components 134), the multiple event reporting requirements received therewith may be merged to an overall event reporting requirement, possibly per NF 140, that is then communicated to the one or more NFs 140.
Using the previous example, AS1 would like to add a new use case (UC2) similar to UC1, but which requires at least 10% sampling on all NFs 140. The event reporting controller 136 will merge the requirements of UC1 and UC2 as follows. On low-loaded NFs 140, it will keep the 100% sampling rate, on heavily-loaded NFs 140, it will raise the rate from 1% to 10%, and on standard daily profile nodes, it will set the rate to 10%, if it is more than 1000 record, or a percentage higher than 10, to satisfy both UCs.
Using the previous examples, a second analytics component 134 (AS2) may have been added to the NM domain 130, which adds a third use-case (UC3) which requires 5% of subscribers to monitored. The event reporting controller 136 will attempt to merge the three UCs, and it will determine that requirements of UC3 have been already met by UC2, so adding this new UC3 will not raise the load on the NFs 140. With current solutions, this step needs to be done manually, or needs to be automated in an integration step during AS deployment, which is quite inflexible.
In the following, several further exemplary UCs will be discussed with reference to the diagrams of
Customer Care (CC) UCs in general require monitoring event for all subscribers because any subscribers can call a CC agent and can complain about service quality, for example (see steps 502 and 504 in
In this UC, event reporting controller 136 receives the IMSI white list dynamically as requirement from the analytics component 134. Since the requirement for this UC is support of IMSI filtering, it is checked by the event reporting controller 136 if a given NF 140 supports IMSI white list filtering and its associated limit (e.g., of the number or the supported IMSIs, or size of the white list). Also, the capacity for adding additional IMSIs to the IMSI white list at the NFs 140 is checked. Some NFs 140 may not support IMSI filtering or use IMSI as whitelist identifier. In this case, the event reporting controller 136 requests the particular analytics component 134 that signaled the UC to provide a mapping to a supported identifier (e.g., IMSI to user equipment, UE, Internet protocol, IP, address, or IMSI to used access point name, APN, or network slice). The required white list is continually updated with the IMSIs (or other identifiers) of the VIP CC subscribers. No KPI precision information is sent in this UC, but it may indicate subscribers which cannot be monitored for some reason (e.g. not enough monitoring capacity at an NF 140). The refreshed white list is sent and updated at the NFs 140, and after that the NFs 140 produce and report events for the updated list of subscribers (steps 510, 512).
In regard to steps 510 and 512, timeout values may be used as system configuration parameters for updating or modifying the whitelist. As an example, dedicated (e.g., VIP) subscribers need not be removed from the whitelist, therefore a timeout value for their SUPIs can be set to infinity (or no timeout is applied). SUPIs of other subscribers that are added to the whitelist due to some detected or signalled problem get a suitable timeout value (e.g., 7 days) during which their SUPIs remain on the list (and get removed when the timeout expires). The timeout value may be selected such that the root cause of a network issue can likely be determined using the event data collected during that time period in the NM domain 130. Using the timeout feature helps to keep the whitelist at a manageable size.
By filtering the events right in the NFs 140 instead of doing it in the analytics components 134 after collecting them for all subscribers saves considerable hardware resources, because data collection (e.g., probing) usually consumes 30-50% of the resources of the analytics components 134. The event reporting controller 136 has access to analytics information such as correlated event records (e.g., via the analytics components 134) and it therefore can instruct NFs 140 of different domains 110, 120 to monitor the same user sessions, even if these are identified by different IDs in the different domains. The solution is integrated into the event reporting control layer and automates otherwise manual processes of merging requirements, administering timeouts, translating the desired whitelist for different types of NFs 140, and so on.
As another example, an incompatibility issue or high failure ratio may be detected for a new terminal type or new software version of an NF 140. In order to detect all related issues, all sessions using the same terminal types are activated in the corresponding NFs 140. This requires IMSI or SUPI whitelist filtering or international mobile equipment identity (IMEI) filtering in the NFs 140, if supported.
In
The number of events required for root cause analysis from the same cell/device type/NF 140 etc. are determined (e.g., by the analytics components 134 or the event reporting controller 136). In case of an NF issue, the simplest method is that reporting of all events is activated at the affected NFs 140. If there is not enough monitoring/reporting capacity, the sampling rate for a target precision is determined (see next section). In case of a subscriber or terminal issue, the affected subscribers are added to the white list of the affected NFs 140. The increased precision of the requested KPIs can indicated to the analytics components (see step 6 in
For example, during normal operation (there is no particular issue) the analytics components 134 require 10% random sampling at each NF 140. This is a relatively low load in terms of monitoring, reporting and processing/analysis compared to 100%. In case an anomaly is detected, e.g., related to a particular network node, terminal type, or other network dimension, more events are needed that are related to the issue in order to identify the affected subscribers s and investigate the root cause. Turning on 100% event collection would be too heavy; therefore, full event reporting is only activated only those entities which are related to affected subscribers. Assume that an NF 140 in the form of an IP multimedia sub-system (IMS) node has failed. In IMS, all events related to this node are activated for reporting (filtering for IMS node IP address). In the CN domain 110, the IMS node IP address is not a valid filtering type, therefore, the analytics component 134 or the event reporting controller 136 identifies which subscribers use the problematic IMS node and control filtering for the associated SUPIs or IMSIs (or other subscriber identifiers), using white list filtering. This white list is optionally merged with the white list determined in the currently running UCs, and data collection is activated for this merged list. In the CN domain, event reporting is done for 10% random sampling and the merged IMSI white list. In this manner coherent event filter settings can be achieved across the CN and RAN domains 110, 120.
N=4Z2σ2/W2,
where Z is the Z score at the desired confidence level, e.g. 95%, a is the standard deviation of the given KPI, and W is the width of the confidence interval the mean value should fell in (with 95%). Note that from this formula, the precision of the KPI W can be determined for a given number of samples and a given confidence level (e.g., if there are not enough sample and one would like to determine how it affects the KPI precision).
Referring to
Filtering and sampling capacities of different NFs 140 may not be sufficient to guarantee enough event data for an analysis with the required KPI prevision. In this context, the event reporting controller 136 continuously received NF reports with the current NF loads and NF capacities of the involved NFs 140. as event sources of the KPIs (step 708). The analytics component 134 may further provide information to the event reporting controller 136 on the number of active subscribers, which is the basis to determine the proper sampling rates and/or whitelists as well as to calculate the achieved precision for the already collected data. The number of required samples are determined for each NF 140. The required sampling and filtering settings are configured at the NFs 140. KPI precision at the current filter setting and/or sampling rate is calculated and reported by the event reporting controller 136 (step 710) to the analytics component 134 where this information can be displayed in addition to the KPI values (step 712). It also can be used in the presentation layer for determining the lowest resolution of the KPI presentation (e.g., 1 min, 5 min, 1 h)
In summary, KPI precision is an important extra information to be attached to the user output of the analytics systems, if any type of partial data collection (sampling and/or whitelist filtering) is used. The event reporting controller 136 may provide two services in this regard: (1) calculating the KPI precision from actual sampling/filtering settings and (2) calculating the required number of data points (to be realized by sampling and/or filtering) to reach a target precision.
In this regard, load distribution among cells is very uneven, as it can be seen in
In the user plane NFs 140 in the CN domain 110, however, there is no information on which data flow belongs to which cell. Therefore, random sampling cannot be applied. In this case, the event reporting controller 136 requests the required number of the active subscriber (e.g., IMSIs or SUPIs) per cell from the analytics component 134 and configures the corresponding number white IMSI or SUPI list or otherwise at the user plane (UP) NFs 140 in the CN domain 110. In this way, the required number of samples is obtained for UP traffic as well as per cell, and the data collection of UP is balanced per cell. Radio event data can be obtained for the same IMSI or SUPI list as well at the radio cell ensuring that the radio data are available for the same session as UP in the correlated event data records in the NM domain 130. In this regard, it is proposed to use representative sampling as follows: collect a higher fraction of data points from small subscriber groups and lower fraction from large groups. The groups can be formed via any dimension of interest, such as location, terminal type, or user category.
With respect to
In step 802, the analytics component 134 determines the event dimensions to be configured as requirements vis-à-vis the event reporting controller 136, optionally together with the associated KPI precision requirements. Also, the actual counts per dimension are calculated based on the event data collected at the actual (i.e., current) sampling rate, see steps 804 and 806, by either the analytics component 134 or the event reporting controller 136. The event reporting controller 136, in step 808, then determines the minimum number of subscriber to be monitored for achieving the required KPI precision per dimension and generates associated event reporting requests for the NFs 140 as needed. The objective of determining a proper event sampling rate at the NFs 140 in the RAN domain 120 is to collect enough and about the same amount of events for each cell. KPI precision values are reported per cell to the analytics component 134 by the event reporting controller 136. The sampling/filtering rate is/are adjusted (increased/decreased) at the RAN NF(s) 140. Based on the correlation of information obtained in the NM domain 130, the user and control plane events are obtained for the same subscribers for the RAN NFs 140 as for the CN NFs 140. Depending on the available event reporting capabilities at the different NFs 140 (see steps 810, 812), representative sampling can be reached with the proper combination of sampling and filtering, especially in a cross-domain analytics scenario. In this manner coherent event filter settings can be achieved across the NFs 140.
In one example, sufficient samples for the UP KPIs and related KPIs in the RAN domain 120 are needed to check if a service quality issue is due to radio problems or not. So UP and RAN KPIs are needed for the same sessions. It is assume here that both CN domain NFs 140 and RAN domain NFs 140 support random sampling. In certain cells the data volume is much more than needed for the required KPI precision, therefore, in these cells one could apply 10% random sampling for the RAN domain 120. But in the CN domain 110 the UP report for the same sessions is needed. So the event reporting controller 136 identifies who are the subscribers for which RAN events are collected and adds these subscribers to the white list of the CN NFs 140. In this way, one collects events at a rate of 10% in the CN domain 110 as well.
A default sampling rate may initially be set for event collection (e.g., as a kind of bootstrapping/self-starting mechanism), see step 814. Note that step 804 already needs the number of actually collected event records broken down by dimension values and the applied sampling rate. From these pieces of information, it is possible to estimate the true number of subscribers broken down by dimension values. This is then used in step 808.
Adding an extra event reporting control layer between the analytics components 134 on the one hand and the CN and RAN domains 110, 120 on the other offers significant advantages. For example, the burden of integrating sampling and filtering control of multiple NF types form multiple vendors is removed, or decoupled, from development and maintenance of the analytics components 134.
Moreover, in the embodiments described above, the event monitoring and reporting “footprint” of the NM domain 130 in the CN domain 110 and RAN domain 120 can be reduced and controlled, which is desirable in particular with the advent of 5G networks and the expected increase of devices, cells and service types. At the same time, the value and flexibility of a legacy-type “full” monitoring and reporting can be maintained.
The event reporting control layer can specifically be implemented using, for example, dynamic event filter settings and dynamic event sampling rates. If, for example, event monitoring and reporting is only required for a particular subscriber set or a particular type of user terminal, this requirement can easily be implemented while keeping the event load low on the side of the NW domain 130. At the same time, KPI precision (i.e., analysis accuracy) can be controlled as needed. Moreover, prevailing loads and capacities in the CN domain 110 and RAN domain 120 can be taken into account when it comes to event monitoring and reporting. As such, monitoring and reporting can flexibly be distributed among NFs 140 and domains 110, 120. For example, cross-domain load balancing becomes possible. The user plane probing load can be reduced in a consistent way while making sure that communication sessions specifically required for particular analytics UCs are still encompassed.
Filing Document | Filing Date | Country | Kind |
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PCT/EP2020/077373 | 9/30/2020 | WO |