Peter Racz

Diameter-based accounting management for wireless services

Accounting is an essential task for commercial service usage, determining the collection of metered data and correlating it into accounting records. The accounting data generated, describing the service usage of users, serves as input for the subsequent charging process. Because of the diversity of IP-based services and the variety of network technologies, a generic accounting management is required, specifically tailored to user and provider needs. A mobile and multi-domain environment determines additional challenges. This work defines a generic, technology-, and service-independent configuration management of accounting in a mobile, heterogeneous, and multi-provider environment. The proposed accounting process enables a user-and service-specific accounting configuration. It is based on the diameter protocol, specifying required extensions, which include new commands and attribute-value-pairs

Mobility and QoS Support for a Commercial Mobile Grid in Akogrimo

Grid networks aim to build a future architecture for efficient resource sharing and distributed service provisioning in a multi-provider environment. However, mobility, QoS support, and commercial service provisioning -all essential issues in future networks -pose new challenges to grid networks, both from a technical and economic point of view. Therefore, the Akogrimo project aims at developing an integrated service architecture for commercial mobile grid networks. This paper presents the Akogrimo architecture and its key characteristics, integrating mobility and network layer QoS support in a commercial grid environment.

Generic accounting configuration management for heterogeneous mobile networks

Accounting performed by network and service providers covers the tasks of determining, collecting, and evaluating information on the service usage of their customers. This information forms the basis of the subsequent charging process. For performing these tasks in case of heterogeneous mobile networks a generic configuration management, specifically tailored at the provisioning of various Internet services is needed. This work defines a role model covering all participating entities of a distributed service provisioning environment for mobile networks together with key requirements. In addition, it outlines different accounting scenarios and proposes an architecture for a generic, technology- and service-independent configuration management of accounting in a distributed, mobile, and multi-provider environment. In turn, the approach specifies required configuration and state information in network components. Finally, a use case with an inter-domain scenario provides an example for the proposed accounting configuration management process.

Integrating trust establishment into routing protocols of today's MANETs

Conventional network protocols and its security mechanisms fail to cope with arising challenges in trust. Well known concepts from the domain of Trusted Computing can be applied to the example of mobile ad-hoc networks (MANETs) in order to establish extended trust capabilities between devices. The approach of such an anchor of trust in MANETs shows interesting possibilities since no central instances such as Access Points are involved in those networks. The communication between directly connected devices of the network is protected by a cryptographic protocol making use of a Trusted Platform Module (TPM) that serves as root-of-trust on each device. Such a hardware chip allows devices to attest the local system state and assess states of remote systems. Building on this, transmission of routing and payload data can be restricted to devices in trustworthy states. The resulting mobile ad-hoc network, by using this protocol, is protected against many of todays security threats. Single malicious devices are automatically recognised and excluded from participation in the network by all devices. Especially the dissemination of misleading routing information, which affects the availability of the whole network, is effectively prevented by the developed protocol. Thus, it is shown that the device itself is secured by a hardware TPM. Also the communication is secured, by verifying the devices state between the counterparts.

SCRIPT: A framework for Scalable Real-time IP Flow Record Analysis

Analysis of IP traffic is highly important, since it determines the starting point of many network management operations, such as intrusion detection, network planning, network monitoring, or accounting and billing. One of the most utilized metering data formats in analysis applications are IP (Internet Protocol) flow records. With the increase of IP traffic, such traffic analysis applications need to cope with a constantly increasing number of flow records. Typically, centralized approaches to IP traffic analysis have scalability problems, which are addressed by replacing existing hardware with more powerful CPUs and faster memory. In contrast, this paper developed and implemented SCRIPT (Scalable Real-time IP Flow Record Analysis), which defines a scalable analysis framework that can be used to distribute flow records to multiple nodes performing traffic analysis in order to balance the overall workload among those nodes. Due to its generic design, the framework developed can be extended and used to distribute other metering data, such as packet headers, payloads, or accounting records.

Grids in a Mobile World: Akogrimo's Network and Business Views

ABSTRACT The use of wireless networking technologies has emerged over recent years in many application domains. The area of grids determines a potentially huge application domain, since the typical centralized computing centers require access from anywhere, e.g., from field engineers who are situated in a wireless network domain. Thus, the integration of suitable business views on mobile grids, of grid views on available technologies, and network views in a fully IP-based network domain determines the key challenge. The Akogrimo projects architecture developed, is outlined and discussed in this paper and provides the major details required to offer a fully integrated and interoperable solution for those three views of concern.

Service-oriented Accounting Configuration Management based on Diameter

The new accounting configuration management based on diameter is highly suitable for wireless and mobile communication systems. The diameter protocol extensions by new commands and new AVPs result in a complete and standard-conforming approach. This paper draws the conclusion that the service-oriented accounting configuration management proposed complies with all requirements defined. The common layer above any network access technology is the IP layer and all diameter extensions proposed fit well. User and service profiles enable mobile and wireless network operators to have the best available flexibility to add new services, assign new services to users, and, by providing the respective accounting definitions, have a user- and service-specific accounting configuration in place

Design and Implementation of a Distributed Platform for Sharing IP Flow Records

Experiments using real traffic traces are of key importance in many network management research fields, such as traffic characterization, intrusion detection, and accounting. Access to such traces is often restricted due to privacy issues; research institutions typically have to sign non-disclosure agreements before accessing such traces from a network operator. Having such restrictions, researchers rarely have more than one source of traffic traces on which to run and validate their experiments. Therefore, this paper develops a Distributed Platform for Sharing IP Flows (DipSIF) based on NetFlow records between multiple institutions. It is assumed that NetFlow traces collected by each participant are archived on separate storage hosts within their premises and then made available to others using a server that acts as a gateway to the storage. Due to privacy reasons the platform presented here uses a prefix-preserving, cryptography-based, and consistent anonymization algorithm in order to comply to different regulations determining the exchange of traffic traces data.

Monitoring of SLA compliances for Hosted Streaming Services

Monitoring of Service Level Objectives (SLOs) determines an essential part of Service Level Agreement (SLA) management, since customers are to be reimbursed, if a provider fails to fulfil them. By automating this process, a timely detection of a violation is possible. The compliance approach must be flexible to adapt to potential changes, must be scalable with respect to the amount of data, and has to support multi-domain environments. This paper determines a Hosted Streaming Services scenario and defines relevant SLOs. Key requirements are derived, the respective architecture is designed, and the approach is implemented prototypically based on a generic auditing framework. Further-more, a new scheme is proposed that considers the degree and duration of SLO violations in calculating reimbursements.

IP flow accounting application for diameter

Flow accounting in IP networks is used by network operators for various purposes, such as network management, traffic management, or traffic analysis. In order to integrate flow accounting into an Authentication, Authorization, and Accounting (AAA) infrastructure, this work designs and evaluates an accounting extension to the Diameter protocol - termed Diameter IP Flow Accounting (IPFA) application - in support of the efficient transfer of IP flow records. The new Diameter IPFA application has been implemented as a prototype and its evaluation shows that it achieves a better performance for the transfer of IP flow records than the traditional Diameter accounting approach.