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WO2009152559A1 - Gestion de pannes dans des réseaux sans fil à large bande - Google Patents

Gestion de pannes dans des réseaux sans fil à large bande Download PDF

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Publication number
WO2009152559A1
WO2009152559A1 PCT/AU2009/000753 AU2009000753W WO2009152559A1 WO 2009152559 A1 WO2009152559 A1 WO 2009152559A1 AU 2009000753 W AU2009000753 W AU 2009000753W WO 2009152559 A1 WO2009152559 A1 WO 2009152559A1
Authority
WO
WIPO (PCT)
Prior art keywords
fault
modem
data
modems
bts
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/AU2009/000753
Other languages
English (en)
Inventor
Philip Allan Ridley
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
UBO Wireless Pty Ltd ACN
Original Assignee
UBO Wireless Pty Ltd ACN
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from AU2008903112A external-priority patent/AU2008903112A0/en
Application filed by UBO Wireless Pty Ltd ACN filed Critical UBO Wireless Pty Ltd ACN
Publication of WO2009152559A1 publication Critical patent/WO2009152559A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/08—Testing, supervising or monitoring using real traffic
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
    • H04L41/02—Standardisation; Integration
    • H04L41/0246—Exchanging or transporting network management information using the Internet; Embedding network management web servers in network elements; Web-services-based protocols
    • H04L41/0253—Exchanging or transporting network management information using the Internet; Embedding network management web servers in network elements; Web-services-based protocols using browsers or web-pages for accessing management information
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
    • H04L41/02—Standardisation; Integration
    • H04L41/0246—Exchanging or transporting network management information using the Internet; Embedding network management web servers in network elements; Web-services-based protocols
    • H04L41/026—Exchanging or transporting network management information using the Internet; Embedding network management web servers in network elements; Web-services-based protocols using e-messaging for transporting management information, e.g. email, instant messaging or chat
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
    • H04L41/06—Management of faults, events, alarms or notifications
    • H04L41/0631—Management of faults, events, alarms or notifications using root cause analysis; using analysis of correlation between notifications, alarms or events based on decision criteria, e.g. hierarchy, tree or time analysis
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L41/00—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks
    • H04L41/22—Arrangements for maintenance, administration or management of data switching networks, e.g. of packet switching networks comprising specially adapted graphical user interfaces [GUI]

Definitions

  • This invention concerns fault management in a wireless broadband network.
  • aspects of the invention include a system, method and software.
  • Wireless broadband networks are created by setting up an array of base stations or base transceiver stations (BTS) throughout a coverage area, and implementing a radio frequency (RF) access technology among them. Subscribers within coverage then access the network using customer premise equipment (CPE), wireless modems or mobile stations.
  • CPE customer premise equipment
  • EMS Element Management Systems
  • Navini Ripwave RF access technologies currently in use to configure and provision BTSs and CPEs for use on such networks.
  • the CPEs have greatly different bandwidth demand behaviour, and there are descriptors, link speeds, in both upload and download paths varying from 32Kbps up to 1024Kbps.
  • the two main influences on overall CPE link speed are BTS congestion and RF path.
  • BTS congestion affects different descriptors at different levels of deterioration in descriptor speed per BTS, but the RF path is unique to each CPE.
  • rarified access to air interface resources affects overall CPE throughout more than RF path for broadband customers.
  • CPEs are smart RF devices, with their own decision-making capabilities. If a CPE is not happy with the current RF quality and resource allocation, it will simply detach itself and search for a new BTS to attach to. Therefore, CPE behaviour is not deterministic. In addition, the CPEs must stay configured as nomadic at all times in order to maintain service portability anywhere within coverage.
  • CSR Customer Service Representatives
  • the invention is a fault management system for a wireless broadband network, that operates automatically to:
  • Periodically compute metrics for each customer modem active on the network Periodically compute metrics for each customer modem active on the network.
  • the modems will typically be embedded in customer premise equipment (CPE), wireless modems or mobile stations.
  • CPE customer premise equipment
  • the system may troubleshoot identified problems using the same data and logic that a human customer services representative (CSR) applies to reported problems.
  • CSR human customer services representative
  • the system is able to provide more useful information to end users, and fixes what it can without manual intervention. Problems that cannot be resolved are reported to a human CSR in a manner which minimises the time necessary for them to manual troubleshoot the modems.
  • the system may gather data from a range of sources:
  • the network provider in which case the data may include BTS history, registrations and migrations, BTS load levels, CPE nomadic status, modem type, and plan speed.
  • EMS Element Management Systems
  • CRM customer relationship management
  • All modems may be checked every night, or failing that at least once every several days.
  • a rule may use pattern matching CPE or BTS or descriptors, and be applied to exclude selected modems from being checked, and therefore govern the checking process.
  • N I interference The problem where a modem is registering with the same frequency on more than one BTS.
  • Locked nomadic BTS A modem is locked to a particular setting BTS. This used to be a solution for some modems but it is no longer a desirable solution.
  • Load balancer activity Load balancer activity which disturbed the modem and caused it to exhibit unstable behaviour.
  • Unicaster activity Unicaster activity which disturbed the modem and caused it to exhibit unstable behaviour. Probable hardware failure Modems where a CSR has already assisted a customer but problems still exist are most likely to be caused by a hardware failure with the modem or power supply.
  • N I Prefer modem to a BTS Manual interference using a non-interfering frequency
  • Fuzzy pattern matching may be applied to the data to construct diagnostic categories . which potentially reliably map to the root causes of problems.
  • the boundaries between various diagnosis categories may be managed by a watcher process, and tuned by acting on the percentage of diagnostic misclassifications over time.
  • a business process management (BPM) framework such as Business Process Execution Language (BPEL) may be included to increase flexibility of the approach to changes in the order of diagnoses at runtime without needing to recompile the application.
  • BPM business process management
  • BPEL Business Process Execution Language
  • Future versions may support Client Access Portal (CAP) integration. This could include the ability to open, add to and close tickets on any generic CRM or trouble ticketing system.
  • CAP Client Access Portal
  • the invention may provide a system that will improve the level of service to the customer base. It may reduce technical CSR activity to an exception management basis, as compared with the current repetitive low-value-added activities. This will reduce calls to the contact centre and decrease the rate of churn. Benefits may include:
  • the invention is a fault management process for a wireless broadband network, comprising the steps of:
  • the invention is software for performing the method.
  • Fig. 1 is a block diagram of the fault management system's processes.
  • the fault management system operates to proactively troubleshoot services without human intervention. It will do this by combining data from a number of sources to determine the root cause of problems, and then attempting to resolve the issue.
  • the system's operating cycle involves the following steps:
  • Steps 10, 20 and 30 are addressed by two application processes which run on the application server, and these are described below in the table below:
  • Process 1 Computing Process 1 computes metrics 10 for metrics each modem every day and classifies modems 20 as sick or healthy. The identity of sick modems are passed to Process 3
  • Storing modem Process 2 retrieves RF data for data 30 modems and caches this in a table.
  • This data is retrieved for use by process 3 when diagnosing modems with suspected poor or noisy RF.
  • a reporting process 60 displays reports and configures settings for the system.
  • the identity of poorly performing modems are passed from the system to a virtual customer support representative (VCSR) 70 for fault diagnosis and remedial action.
  • VCSR virtual customer support representative
  • the VCSR comprises a further application process, the diagnoser 40 and a Repair module 50.
  • Diagnoser 40 operates according to the table below:
  • diagnosis 40 A diagnoser performs fault diagnosis of problems and outputs the probably root cause.
  • diagnoser 40 identifies the root cause of the fault.
  • the table below indicates the descriptions of symptoms and their probable root cause:
  • N I interference
  • a modem is registering with the same frequency on more than one BTS.
  • Locked nomadic BTS A modem is locked to a particular setting BTS.
  • Load balancer activity Load balancer activity which disturbed the modem and caused it to exhibit unstable behaviour.
  • Unicaster activity Unicaster activity which disturbed the modem and caused it to exhibit unstable behaviour.
  • Probable hardware failure Modems where a CSR has already assisted a customer but problems still exist are most likely to be caused by a hardware failure with the modem or power supply.
  • a breakdown of the actions to be performed by repair module 50 for each fault is given in the table below. Apart from the probable hardware failure and unknown root causes, all actions involve an automatic step to fix the problem identified.
  • N I Prefer modem to a BTS Manual interference using a non-interfering frequency
  • the system relies on data feeds for usage and DHCP lease information from collector processes 80. This data is variable depending on the level of usage by the customer. For example, if a customer has turned off the modem for the last fourteen days, then no usage or DHCP lease information will exist.
  • the application processes cycle through a database of every modem on the network daily, combining information gathered from several different sources to identify poorly performing services or services that have degraded recently. In each cycle some modems may be excluded from the process 90.
  • Process 1 will compute service quality metrics for each modem daily.
  • Stabilitylndex a function of (registrations, usage, DHCP/PPPoE)
  • PeakSpeed (PSI) a function of (BTSJoad, RF Path, cpe_descriptor)
  • UsageProfile (UP) : a function of (DHCP/PPPoe, usage) A 14-day window going backward in time from the current day and time will be used to compute each measure. Rationale: SI indicates the stability of the connection and measures the ability to connect and stay connected to the network. PSI measures how fast the connection was from the user's perspective. UP indicates how often the customer used the service.
  • Process 1 will compute the SI for every modem daily
  • SI consists of three parameters to indicate the stability of a customer connection:
  • DHCP IP Thre (number of unique IPs past 24 hours) The SI will be a number between 0 and 1 : • 0 indicates poor stability
  • a service which is not used will have a SI value of 1.
  • Process 1 will compute the PSI for every modem daily.
  • PSI consists of two subindexes (how fast was the connection when used)
  • the PSI will be a number between 0 and 1 :
  • PSI is given a value of -1.
  • Rationale A relationship exists between the BTS congestion measure and the user's perceived speed.
  • Process 1 will compute the UP for every modem daily.
  • the UP will be a number between 0 and 1 :
  • Process 1 classifies modems with a SI value less than a threshold as poorly performing and these are then sent to VCSR 70 for fault diagnosis and fixing.
  • SI index threshold is configurable at runtime and be used to filter poorly performing modems. Rationale: SI is the strongest indicator of a customer's user experience.
  • a high registration count is strongly correlated with poor user experience.
  • Process 1 will classify modems with a SI value that drops more than a threshold over a 30 day period as poorly performing and then send them to VCSR 70 for fault diagnosis and fixing.
  • the daily SI value will be compared with the value from 30 days ago. If there is a drop in SI more than a given threshold then the modem shall be classified as poorly performed and then sent to VCSR for fault diagnosis.
  • the threshold is a relative value and different to the absolute threshold in the above requirement. It shall be configurable at runtime.
  • Process 1 classifies modems with a PSI value less than a threshold as poorly performing BUT will be not send them to VCSR for fault diagnosis and fixing.
  • the SI index threshold shall be configurable at runtime and be used to filter poorly performing modems. Note: A future version may pass modems with a poor PSI to the diagnoser and it could get preferred to alternate BTS. Rationale: Bad PSI values occur as a result of BTS congestion. Unlike poor modems with low SI where an immediate remedy is possible, BTS congestion doesn't have a simple solution besides adding a future feature in the load balancer for this.
  • Process 1 will compute an overall Service Quality Index as a combined measure of the SI and PSI value for each modem.
  • the SQI is a binary measure, "good” or "bad”.
  • the SQI is good if both SI and PSI daily values are not less below the respective thresholds. If either or both measures are below the respective thresholds then the SQI is bad.
  • the RF Cache will attempt to retrieve air interface data for poorly performing modems for each registration event
  • Each registration event triggers an event in the RF Cache to attempt to retrieve air interface data for the modem.
  • the RF Cache checks the last value of a Stability Index (see below). If this value is below a threshold, then the RF Cache attempts to retrieve a maximum of three air interface samples.
  • the air interface samples include the following:
  • VCSR 70 will investigate the problem modems identified by the application processes 1 and 2 and determine the most likely cause of the faults.
  • VCSR 70 comprises both Process 3, the Diagnoser 40 and the Action/Repair
  • Diagnoser 40 will determine the root cause of a poor performing modem as one of seven possible faults.
  • the diagnoser 40 may do peak detection to determine if an increase in modem registrations corresponds to load balancer activity.
  • the diagnoser may do the following for a day with load balancer activity
  • steps 1 -3 should be performed for each load balancer event in the time window of interest. If one or more occurrences of load balancer activity are flagged in step 3, the overall diagnosis is considered to be due to the load balancer.
  • ⁇ Diagnoser 40 may do multiple diagnoses and determine the most likely root cause.
  • ⁇ Diagnoser 40 will include cell edge detection as a future root cause.
  • the diagnoser 40 may use RF cache data to discriminate further and determine if a modem is located on a cell edge. Rationale: This requirement is useful for RF planning.
  • ⁇ Diagnoser 40 may do a trend analysis of modem registrations to determine if poor performance is due to a hardware failure.
  • Modem and power supply hardware failures are characterised by a sharp increase in the number of registrations. This occurs without any influence due to from the load balancer or Unicaster.
  • the diagnoser may use trend analysis of the CPE registration graph to automatically determine if the cause of a fault is most likely due to a hardware failure.
  • ⁇ Diagnoser 40 may search the home BTS list to determine if a modem has been badly preferred to a particular BTS.
  • a modem it is possible for a modem to be preferred to a BTS which is not appropriate given its home BTS list. The requirement is to search the BTS list and determine if the modem has been wrongly preferred to a BTS.
  • VCSR 70 will attempt to fix some connectivity issues by moving and/or preferring the CPE, other faults will prompt the VCSR to email the customer while others will require a CSR to call the customer and/or send replacement hardware.
  • the following requirements detail what actions, either automatic or manual, will be performed for each root cause.
  • repairer 50 will attempt to find an alternate BTS which doesn't result in interference and prefer the modem to it.
  • repairer 50 will find an alternate modem which supports the following:
  • the modem has registered with this BTS frequently in the past to ensure it has a high likelihood of receiving service.
  • repairer 50 can find an alternate BTS then it shall prefer the modem to this BTS. If repairer 50 cannot find an alternate BTS then no action will be performed. Rationale: Preferring the modem to a BTS is safe from the viewpoint that it can still register with other BTS 's.
  • Repairer 50 will automatically unlock modems which have been locked to a single BTS.
  • APPROVED Repairer 50 will use the existing interface to the EMS system Version 2.0 to unlock the modem. Automatic unlocking of modems means no manual action by a CSR is performed.
  • Repairer 50 will automatically exclude those modems from load balancing which have been determined as sick due to previous load balancing activity.
  • Repairer 50 will add the modem to the excluded list in the database. Automatic exclusion of the modem from load balancing means no manual action by a CSR is performed. An exemption period will apply to the exclusion from load balancer. The exemption period will be a default value of 14 days. The period shall be configurable from the user interface.
  • Repairer 50 will automatically send an email to the customer to reposition their modem when it has been diagnosed with poor or noisy RF
  • Repairer 50 will provide an ability to turn on or off the automated actions specified in the preceding requirements selectable at runtime.
  • the user-interface will include the capability to turn on or off at runtime these automated actions:
  • the Admin subtab contains settings for configuring VCSR..
  • the Admin subtab contains settings for configuring VCSR:
  • the History subtab contains graphical data that describes VCSR activity overall.
  • the History Subtab contains the following reports that can be obtained on demand.
  • the Actioned subtab contains tabular information that depicts the state of all CPEs actively being worked on or monitored by VCSR.
  • the Action SubTab contains a web form and results section that finds and displays:
  • the Actioned subtab provides the capability to suppress CPEs from being reported for 14 days.
  • the Action sub Tab includes a checkbox to suppress CPEs from being reported. This will ensure the CPE is never reported in the Diagnosis and search sub tabs for 14 days.
  • the Not Actioned subtab shows modems requiring attention by a CSR
  • the Not Actioned subtab includes a list of modems which cannot be fixed by VCSR. This includes modem diagnosed with the following root causes:
  • the Search subtab provides a drop down box with a search capability for a given CPE or list CPEs with different types of faults.
  • the Search subtab provides a drop down box with individual CPE, a period and CPE filter.
  • the user shall be able to run a query for an individual CPE, find flagged CPEs and filter for different faults.
  • the drop down box will allow the user to choose from
  • the results from a search shall be as shown in Error! Reference source not found.
  • the results for each CPE shall be available as shown in Error! Reference source not found, by clicking the -J icon.
  • An individual CPE can be searched from the CPE filter box.
  • the Lifecycle subtab displays graphical data for the total user population and churned customers.
  • the Lifecycle subtab displays daily, weekly, monthly SQI, SI, PSI and UP data for the total user population. It will show the data for churned customers for the same time periods.
  • the History subtab displays the number of fixed modems in the last 28 days for VCSR affected modems.
  • the History subtab displays plots with:
  • a fixed modem is one that contains a higher average SI for the last 7 days of the period (before VCSR diagnosed it) compared with the most recent 7 days. This is illustrated in the figure below. Similar to (1), a modem not fixed, (2), is one with a lower average SI value over the same period as (1).
  • VCSR 70 includes changes in the existing CPE performance tab to display VCSR activity for the CPE and provide a recent fault diagnosis if it exists.
  • VCSR Last Diagnosis This should show Diagnosis, Action and Date each separated by a comma.
  • VCSR exempted (days) This shows a number in days that the modem is exempted for.
  • the CPE performance tab provides an instant VCSR fault diagnosis button.
  • the CPE performance tab provides a button to allow an instant fault diagnosis to be performed. Pressing the button invokes the fault diagnoser process 40 to determine the likely root cause of a fault.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Computer And Data Communications (AREA)
  • Telephonic Communication Services (AREA)
  • Maintenance And Management Of Digital Transmission (AREA)

Abstract

L'invention concerne une gestion de pannes dans un réseau sans fil à large bande. Dans des aspects particuliers, l'invention est un système, un procédé et un logiciel. Le système de gestion de pannes fonctionne automatiquement pour : calculer périodiquement des métriques pour chaque modem de client actif sur le réseau, identifier les modems en panne à partir de leurs métriques calculées, stocker les données RF des modems en panne, réaliser un diagnostic de panne à l'aide des données stockées pour identifier la cause racine la plus probable de la panne, et corriger la cause racine la plus probable de la panne.
PCT/AU2009/000753 2008-06-18 2009-06-15 Gestion de pannes dans des réseaux sans fil à large bande Ceased WO2009152559A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
AU2008903112A AU2008903112A0 (en) 2008-06-18 Fault Management in Wireless Broadband Networks
AU2008903112 2008-06-18

Publications (1)

Publication Number Publication Date
WO2009152559A1 true WO2009152559A1 (fr) 2009-12-23

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PCT/AU2009/000753 Ceased WO2009152559A1 (fr) 2008-06-18 2009-06-15 Gestion de pannes dans des réseaux sans fil à large bande

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WO (1) WO2009152559A1 (fr)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020056132A1 (en) * 2000-01-26 2002-05-09 Vyyo Ltd. Distributed processing for optimal QOS in a broadband access system
US20020152303A1 (en) * 2000-10-17 2002-10-17 Steve Dispensa Performance management system
EP1562390A1 (fr) * 2004-02-09 2005-08-10 Alcatel Connexion à large bande à haute disponibilité par commutation d'un réseau filaire à des réseaux sans fil

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020056132A1 (en) * 2000-01-26 2002-05-09 Vyyo Ltd. Distributed processing for optimal QOS in a broadband access system
US20020152303A1 (en) * 2000-10-17 2002-10-17 Steve Dispensa Performance management system
EP1562390A1 (fr) * 2004-02-09 2005-08-10 Alcatel Connexion à large bande à haute disponibilité par commutation d'un réseau filaire à des réseaux sans fil

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