Stefan Wallin | Luleå University of Technology (original) (raw)

Papers by Stefan Wallin

International Journal of Network Management, 2011

ABSTRACT The development and integration of an alarm interface between network elements and a net... more ABSTRACT The development and integration of an alarm interface between network elements and a network management system is a costly process, largely because of the informal way in which alarm interfaces are expressed and communicated. Low-quality alarm documentation and confusion around fundamental concepts like alarm states and alarm types are typical consequences of current practices. If alarm interfaces were expressed in a more formal manner, costs could be reduced and more advanced analysis and automation would be enabled. We present a novel approach to alarm interfaces by providing a formal alarm model together with a domain-specific language that allows us to specify both the alarm models and the constraints placed on the alarm models in a consistent manner. This means that we can verify the consistency of an alarm interface and automatically generate artifacts such as alarm correlation rules or alarm documentation based only on the model. Copyright © 2011 John Wiley & Sons, Ltd.

Lecture Notes in Computer Science, 2009

It is hard to know which research problems in network management we should focus our attention on... more It is hard to know which research problems in network management we should focus our attention on. To remedy this situation we have surveyed fifteen different telecom operators on four continents to gather some feedback on what they desire and expect from the network management research community. Their input forms a foundation for future directions in network management research, and provides us with valuable insight into what the most urgent problems are in industry.

2012 IEEE Network Operations and Management Symposium, 2012

ABSTRACT Network Service Providers are struggling to reduce cost and still improve customer satis... more ABSTRACT Network Service Providers are struggling to reduce cost and still improve customer satisfaction. We have looked at three underlying challenges to achieve these goals; an overwhelming flow of low-quality alarms, understanding the structure and quality of the delivered services, and automation of service configuration. This thesis proposes solutions in these areas based on domain-specific languages, data-mining and self-learning. Most of the solutions have been validated based on data from a large service provider. We look at how domain-models can be used to capture explicit knowledge for alarms and services. In addition, we apply data-mining and self-learning techniques to capture tacit knowledge. The validation shows that models improve the quality of alarm and service models, and enables automatic rendering of functions like root cause correlation, service and SLA status, as well as service configuration. The data-mining and self-learning solutions show that we can learn from available decisions made by experts and automatically assign alarm priorities.

21st International Conference on Advanced Information Networking and Applications Workshops (AINAW'07), 2007

ABSTRACT Telecom operators face an increasing need for service quality management to cope with co... more ABSTRACT Telecom operators face an increasing need for service quality management to cope with competition and complex service portfolios in the mobile sector. Improvements in this area can lead to significant market benefits for operators in highly competitive markets. We propose an architecture for a service monitoring tool, including a time aware formal language for model specification. Using these models allows for increased predictability and flexibility in a constantly changing environment.

ABSTRACT Network providers are challenged by new requirements for fast and error-free service tur... more ABSTRACT Network providers are challenged by new requirements for fast and error-free service turn-up. Existing approaches to configuration management such as CLI scripting, device-specific adapters, and entrenched commercial tools are an impediment to meeting these new requirements. Up until recently, there has been no standard way of configuring network devices other then SNMP and SNMP is not optimal for configuration management. The IETF has released NETCONF and YANG which are standards focusing on Configuration management. We have validated that NETCONF and YANG greatly simplify the configuration management of devices and services and still provide good performance. Our performance tests are run in a cloud managing 2000 devices. Our work can help existing vendors and service providers to validate a standardized way to build configuration management solutions.

2008 IEEE International Symposium on Service-Oriented System Engineering, 2008

To be able to monitor complex services and examine their properties we need a modeling language t... more To be able to monitor complex services and examine their properties we need a modeling language that can express them in an efficient manner. As telecom operators deploy and sell increasingly complex services the need to monitor these services increases.

IT Professional, 2006

A s with any technology, it's important to focus management solutions on the users, even when the... more A s with any technology, it's important to focus management solutions on the users, even when the users are those providing a service. In that broader context, network management has three types of "users": network operators, which must earn money on their services, network service users (business and consumer), who pay for using services, and network administrators, who staff the network operations center. All three user types benefit from a well-thought-out management solution: operators increase their profits, service users get better service, and administrators streamline their workload.

International Journal of Business Intelligence and Data Mining, 2009

Telecom service providers are faced with an overwhelming flow of alarms, which makes good alarm c... more Telecom service providers are faced with an overwhelming flow of alarms, which makes good alarm classification and prioritisation very important. This paper first provides statistical analysis of data collected from a real-world alarm flow and then presents a quantitative characterisation of the alarm situation. Using data from the trouble ticketing system as a reference, we examine the relationship between mechanical

There is a growing need for telecom operators to be able to model and monitor the services that t... more There is a growing need for telecom operators to be able to model and monitor the services that they offer, to this end a suitable service modeling language is needed. Being able to efficiently monitor services would enable an increase in the quality of the services delivered. We propose a declarative service modeling language called SALmon, which a language for the domain which can be implemented efficiently. This language can serve both as a basis for a service management system, and as a starting point for further examination of this class of languages.

Mobility is gaining a tremendous interest among Internet users and wireless access networks are i... more Mobility is gaining a tremendous interest among Internet users and wireless access networks are increasingly being installed to enable mobile usage. Internet mobility requires solutions to move between access networks with maintained network connectivity. Seamless mobility in turn means that the experience of using a service is unaffected while being mobile. Communication in next generation networks will use multiple access technologies, creating a heterogeneous network environment. Further, roaming between network service providers may take place. To enable mobile nodes to move between access networks within as well as between network service providers with minimal disruption, nodes should be able to maintain multiple active network connections. With the usage of multihomed nodes, seamless mobility can be achieved in already installed infrastructures, not providing mobility support. Mobility in heterogeneous access networks also requires network selections that scale for services. In this article we propose an architecture where application service providers and network service providers define service levels to be used by a mobile node and its user. The user selects a service and the service level from an application service provider. When performing access network selection, information received as part of an application service level will be used to find a network that supports the service required. The performance of available access networks will be monitored and considered when making the decision. Our proposed architecture provides solutions to move flows between interfaces in real-time based on network performance, quality of service signalling to correspondent nodes, and cancellation of flows to give way for more important traffic.

International Journal of Network Management, 2011

ABSTRACT The development and integration of an alarm interface between network elements and a net... more ABSTRACT The development and integration of an alarm interface between network elements and a network management system is a costly process, largely because of the informal way in which alarm interfaces are expressed and communicated. Low-quality alarm documentation and confusion around fundamental concepts like alarm states and alarm types are typical consequences of current practices. If alarm interfaces were expressed in a more formal manner, costs could be reduced and more advanced analysis and automation would be enabled. We present a novel approach to alarm interfaces by providing a formal alarm model together with a domain-specific language that allows us to specify both the alarm models and the constraints placed on the alarm models in a consistent manner. This means that we can verify the consistency of an alarm interface and automatically generate artifacts such as alarm correlation rules or alarm documentation based only on the model. Copyright © 2011 John Wiley & Sons, Ltd.

Lecture Notes in Computer Science, 2009

It is hard to know which research problems in network management we should focus our attention on... more It is hard to know which research problems in network management we should focus our attention on. To remedy this situation we have surveyed fifteen different telecom operators on four continents to gather some feedback on what they desire and expect from the network management research community. Their input forms a foundation for future directions in network management research, and provides us with valuable insight into what the most urgent problems are in industry.

2012 IEEE Network Operations and Management Symposium, 2012

ABSTRACT Network Service Providers are struggling to reduce cost and still improve customer satis... more ABSTRACT Network Service Providers are struggling to reduce cost and still improve customer satisfaction. We have looked at three underlying challenges to achieve these goals; an overwhelming flow of low-quality alarms, understanding the structure and quality of the delivered services, and automation of service configuration. This thesis proposes solutions in these areas based on domain-specific languages, data-mining and self-learning. Most of the solutions have been validated based on data from a large service provider. We look at how domain-models can be used to capture explicit knowledge for alarms and services. In addition, we apply data-mining and self-learning techniques to capture tacit knowledge. The validation shows that models improve the quality of alarm and service models, and enables automatic rendering of functions like root cause correlation, service and SLA status, as well as service configuration. The data-mining and self-learning solutions show that we can learn from available decisions made by experts and automatically assign alarm priorities.

21st International Conference on Advanced Information Networking and Applications Workshops (AINAW'07), 2007

ABSTRACT Telecom operators face an increasing need for service quality management to cope with co... more ABSTRACT Telecom operators face an increasing need for service quality management to cope with competition and complex service portfolios in the mobile sector. Improvements in this area can lead to significant market benefits for operators in highly competitive markets. We propose an architecture for a service monitoring tool, including a time aware formal language for model specification. Using these models allows for increased predictability and flexibility in a constantly changing environment.

ABSTRACT Network providers are challenged by new requirements for fast and error-free service tur... more ABSTRACT Network providers are challenged by new requirements for fast and error-free service turn-up. Existing approaches to configuration management such as CLI scripting, device-specific adapters, and entrenched commercial tools are an impediment to meeting these new requirements. Up until recently, there has been no standard way of configuring network devices other then SNMP and SNMP is not optimal for configuration management. The IETF has released NETCONF and YANG which are standards focusing on Configuration management. We have validated that NETCONF and YANG greatly simplify the configuration management of devices and services and still provide good performance. Our performance tests are run in a cloud managing 2000 devices. Our work can help existing vendors and service providers to validate a standardized way to build configuration management solutions.

2008 IEEE International Symposium on Service-Oriented System Engineering, 2008

To be able to monitor complex services and examine their properties we need a modeling language t... more To be able to monitor complex services and examine their properties we need a modeling language that can express them in an efficient manner. As telecom operators deploy and sell increasingly complex services the need to monitor these services increases.

IT Professional, 2006

A s with any technology, it's important to focus management solutions on the users, even when the... more A s with any technology, it's important to focus management solutions on the users, even when the users are those providing a service. In that broader context, network management has three types of "users": network operators, which must earn money on their services, network service users (business and consumer), who pay for using services, and network administrators, who staff the network operations center. All three user types benefit from a well-thought-out management solution: operators increase their profits, service users get better service, and administrators streamline their workload.

International Journal of Business Intelligence and Data Mining, 2009

Telecom service providers are faced with an overwhelming flow of alarms, which makes good alarm c... more Telecom service providers are faced with an overwhelming flow of alarms, which makes good alarm classification and prioritisation very important. This paper first provides statistical analysis of data collected from a real-world alarm flow and then presents a quantitative characterisation of the alarm situation. Using data from the trouble ticketing system as a reference, we examine the relationship between mechanical

There is a growing need for telecom operators to be able to model and monitor the services that t... more There is a growing need for telecom operators to be able to model and monitor the services that they offer, to this end a suitable service modeling language is needed. Being able to efficiently monitor services would enable an increase in the quality of the services delivered. We propose a declarative service modeling language called SALmon, which a language for the domain which can be implemented efficiently. This language can serve both as a basis for a service management system, and as a starting point for further examination of this class of languages.

Mobility is gaining a tremendous interest among Internet users and wireless access networks are i... more Mobility is gaining a tremendous interest among Internet users and wireless access networks are increasingly being installed to enable mobile usage. Internet mobility requires solutions to move between access networks with maintained network connectivity. Seamless mobility in turn means that the experience of using a service is unaffected while being mobile. Communication in next generation networks will use multiple access technologies, creating a heterogeneous network environment. Further, roaming between network service providers may take place. To enable mobile nodes to move between access networks within as well as between network service providers with minimal disruption, nodes should be able to maintain multiple active network connections. With the usage of multihomed nodes, seamless mobility can be achieved in already installed infrastructures, not providing mobility support. Mobility in heterogeneous access networks also requires network selections that scale for services. In this article we propose an architecture where application service providers and network service providers define service levels to be used by a mobile node and its user. The user selects a service and the service level from an application service provider. When performing access network selection, information received as part of an application service level will be used to find a network that supports the service required. The performance of available access networks will be monitored and considered when making the decision. Our proposed architecture provides solutions to move flows between interfaces in real-time based on network performance, quality of service signalling to correspondent nodes, and cancellation of flows to give way for more important traffic.