Donald Baker

IEEE 802.21: Media independent handover: Features, applicability, and realization

Providing users of multi-interface devices the ability to roam between different access networks is becoming a key requirement for service providers. The availability of multiple mobile broadband access technologies, together with the increasing use of real-time multimedia applications, is creating strong demand for handover solutions that can seamlessly and securely transition user sessions across different access technologies. A key challenge to meeting this growing demand is to ensure handover performance, measured in terms of latency and loss. In addition, handover solutions must allow service providers, application providers, and other entities to implement handover policies based on a variety of operational and business requirements. Therefore, standards are required that can facilitate seamless handover between such heterogeneous access networks and that can work with multiple mobility management mechanisms. The IEEE 802.21 standard addresses this problem space by providing a media-independent framework and associated services to enable seamless handover between heterogeneous access technologies. In this article, we discuss how the IEEE 802.21 standard framework and services are addressing the challenges of seamless mobility for multi-interface devices. In addition, we describe and discuss design considerations for a proof-of-concept IEEE 802.21 implementation and share practical insights into how this standard can optimize handover performance.

Managing process and service fusion in virtual enterprises

Abstract Virtual Enterprises (VEs) are businesses providing services and products that rely on the resources of multiple enterprises. VEs can achieve their business objectives only through effective collaboration between the autonomous enterprises that comprise them. In this paper we advocate the position that effective multi-enterprise collaboration can be achieved by integrating the business processes of the participant enterprises, and by managing the resulting multi-enterprise (business) processes . A key requirement for this is developing multi-enterprise processes that explicitly capture and manage the functional and contractual relationships between the enterprises in a VE. In particular, this includes the inter-enterprise services each enterprise in a VE provides to others as needed to realize multi-enterprise processes. Current process management technology does not deal with the heterogeneity and autonomy of the processes that need to be integrated in a multi-enterprise process. In addition, existing solutions that combine services and multi-enterprise processes either lead to specification explosion or disallow conversations between process activities and services. The Collaboration Management Infrastructure (CMI) addresses these problems by extending an advanced workflow model with a comprehensive set of service management primitives. These include service interfaces, service activities, primitives for coordinating service activities, service wrapper processes, as well as service quality and contracts. A CMI system that supports these has been developed by integrating existing software components, such as a commercial workflow system, with several prototype engines and tools that support the new primitives for multi-enterprise process and service management. To illustrate how CMI supports these, we use multi-enterprise process and service examples from the telecommunications industry.

Managing escalation of collaboration processes in crisis mitigation situations

Processes for crisis mitigation must permit coordination flexibility and dynamic change to empower crisis mitigation coordinators and experts to deal with unexpected situations. However, such mitigation processes must also provide enough structure to prevent chaotic response and increase mitigation effectiveness. Such combination of structure and flexibility cannot be effectively supported by existing workflow or groupware technologies. In this paper, we introduce the Collaboration Management Infrastructure (CMI) and describe its capabilities for supporting crisis mitigation processes. CMI provides a comprehensive Collaboration Management Model (CMM) and a corresponding federated system. CMM supports process templates that provide the initial activities, control and data flow structure, and resources needed to start mitigating a variety of crisis situations. In the event of a crisis, the appropriate process template is selected and instantiated. Crisis mitigation is achieved by escalating the instantiated process template. Escalation involves selecting and adding new process templates, creating new activities, roles, and task forces as needed to deal with the current demands in the crisis, and delegating responsibilities to process participants and task forces. CMM provides advanced composable primitives that empower crisis mitigation coordinators and experts to escalate the process. We provide an overview of the implementation of a federated CMI system and discuss our initial experience with various applications in the area of crisis management.

Providing customized process and situation awareness in the collaboration management infrastructure

Collaboration management involves capturing the collaboration process, coordinating the activities of the participating applications and humans, and/or providing awareness, i.e., information that is highly relevant to a specific role and situation of a process participant. We propose an awareness provisioning solution that allows customization of the awareness delivered to each process participant. Unlike existing collaboration management technologies (such as workflow and groupware) that provide only a few built-in awareness choices, the proposed awareness solution allows the specification of what information is to be given to what users and at what time. To support this advanced level of awareness, we require the definition of awareness roles and the specification of corresponding awareness descriptions. Awareness roles can be dynamically created and associated with any process scope. Awareness descriptions define what information is to be given to users in an awareness role. Since awareness roles are created or become visible when they are needed, the existence of an awareness role also determines the appropriate time interval during which the information specified in the awareness description can be delivered. This customized awareness provisioning approach minimizes information overloading and allows the combination of process-relevant information with external information as needed by the process participants. The proposed awareness provisioning solution is employed by the Collaboration Management Infrastructure (CMI), a federated system for collaboration process management. Examples from the crisis management domain are presented.

Computing diagnostic explanations of network faults from monitoring data

Network fault diagnosis is an important aspect of network management. Often, a single component failure will result in a cascade of secondary faults that overwhelm simple reasoning approaches. If the network monitoring information is being transmitted through the network to the network management system (NMS), then fault diagnosis is complicated by the fact that the transmission of relevant monitoring information for fault diagnosis may be blocked either by the fault itself, or by the faultpsilas effects on the network. Without perfect knowledge, the best fault diagnosis algorithm must properly reason about a number of competing diagnostic explanations that are compatible with the ambiguous networking monitoring information known to the NMS. We describe a novel algorithm for computing all such possible diagnostic explanations and their relative likelihoods, thus providing a complete diagnosis of the network state that can be effectively used by an NMS to correct or mitigate faults. The algorithm uses a variant of classic Boolean satisfiability to efficiently and compactly represent the space of possible explanations. The proposed approach is well suited for networks with (semi-)autonomous management domains organized into a larger management hierarchy, a feature common to many military networks.

The collaboration management infrastructure

The Collaboration Management lnfrastructure (CMI) has been developed at MCC to manage collaboration processes in both traditional and virtual enterprises, and to provide combined process and situation awareness. CMI technology development is driven by the requirements of many advanced applications provided by the companies that are members of the consortial CMI project. Such advanced applications include crisis mitigation, command and control, logistics, and service provisioning in virtual enterprises. These applications are not effectively supported by existing workflow and groupware technologies. To address the requirements imposed by these applications CMI provides a sophisticated Collaboration Management Model (CMM) and a corresponding component-oriented system that implements the CMM. CMM draws existing primitives from workflow and groupware models and introduces new primitives that address previously unsupported requirements of the CMI driver applications. In this paper, a crisis mitigation application is presented that involves several process templates which are extended dynamically as details about the crisis become known.

AWARENESS PROVISIONING IN COLLABORATION MANAGEMENT

Collaboration management involves capturing the collaboration process, coordinating the activities of the participating applications and humans, and/or providing awareness, i.e. information that is highly relevant to a specific role and situation of a process participant. In this paper, we propose an awareness provisioning solution that allows focusing, customizing, and temporally constraining the awareness delivered to each process participant. Unlike existing collaboration management technologies (such as workflow and groupware) that provide only a few built-in awareness choices, the proposed awareness solution allows the specification of what information is to be given to what users and at what time. To support this advanced level of awareness, we require the definition of awareness roles and the specification of corresponding awareness descriptions. Awareness roles can be dynamically created and associated with any process scope. Awareness descriptions define what information is to be given to users in an awareness role. Since awareness roles are created or become visible when they are needed, the existence of an awareness role also determines the appropriate time interval during which the information specified in the awareness description can be delivered. This awareness provisioning approach minimizes information overloading and allows the combination of process-relevant information with external information as needed by the process participants. The proposed awareness provisioning solution is employed by the Collaboration Management Infrastructure (CMI), a federated system for collaboration process management. In this paper, we introduce an Awareness Model (AM) for creating awareness specifications and defining related execution semantics. Awareness specifications in AM are specialized composite event specifications that define patterns of process-related events and external events, as well as how information should be digested from them. We also describe the implementation of CMIs awareness provisioning engine and related tools.

Realization of IEEE 802.21 services and preauthentication framework

Providing users of multi-interface devices the ability to roam between different access networks is becoming a key requirement for service providers. The availability of multiple mobile broadband access technologies together with increasing use of real time multimedia applications is creating strong demand for handover solutions that can seamlessly and securely transfer user sessions across different access technologies. In this paper, we discuss how the IEEE 802.21 standard and its services address the challenges of seamless mobility for multi-interface devices. We focus on a proof-of-concept implementation that integrates IEEE 802.21 services and a pre-authentication framework, realizing different possible usage scenarios to optimize handover performance. We describe the implementation of two handover scenarios using the 802.21 Services: the first one is initiated by the mobile node and the second one is initiated by the operator network. We compare the two scenarios and discuss their respective benefits. Finally, we describe the implementation challenges and lessons learned through this exercise.

Process-Based E-Service Composition for Modeling and Automating Zero Latency Supply Chains

E-services are teams of applications and humans (participating electronically) that work together to provide a service or a product. Virtual Enterprises (VEs) are business or organizations that provide products or services that are created and managed by combining and wrapping e-services provided by multiple independent enterprises. To operate efficiently VEs must form supply chains that utilize and manage e-services. In this paper, we propose a Service Oriented Process model (SOP) and describe the architecture and the basic design principles of the Collaboration Management Infrastructure (CMI), a system that supports SOP. SOP permits modeling of e-services and provides for e-service integration to construct efficient multi-enterprise supply chains. This is accomplished by modeling composite e-services as Multi-Enterprise Processes (MEPs). In particular, SOP supports service activities for modeling the services themselves, primitives for composing supply chains from services, and primitives for automating service coordination as required by a supply chain. The CMI system implements SOP and uses a semantic broker that has knowledge about the service capabilities an quality. Therefore, a MEP (and hence its supply chain) is capable of on-the-fly choice of the service providers that are best suited to its objectives (e.g., cheapest or fastest).

Event-driven Video Awareness Providing Physical Security

The Video Event Awareness Workbench (VEAW) analyzes surveillance video from thousands of video cameras and automatically detects complex events in near-real-time-at pace with their input video streams. For events of interest to security personnel, VEAW generates and routes alerts and related video evidence to subscribing security personnel. Complex event processing in VEAW is driven by user-authored awareness specifications comprised of inter-connected spatio-temporal stream and statistical operators that consume and produce events described in VEAW’s surveillance ontology. In this paper we introduce VEAW’s event driven architecture and describe its solutions for automating video surveillance, including the orchestration of continuous and tasked video analysis algorithms (e.g., for entity tracking and identification), fusion of events from multiple sources in an installation-specific “world” model, and proactive information gathering to deal with missing or incomplete information (this is done by tasking video analysis algorithms and security personnel to provide it). We also discuss how VEAW deals with late arriving information (due to out-of-band video analysis tasks and overhead), as well as a related resource optimization aimed at minimizing computation costs. We illustrate the benefits of VEAW by illustrating its application on the automation of real-world security policies.