David Schmitz

A framework for failure impact analysis and recovery with respect to service level agreements

In todays IT service market customers urge providers to grant guarantees for quality of service (QoS) which are laid down in service level agreements (SLAs). To satisfy customers and to avoid penalties, service providers have to ensure that the agreed SLAs are met. Therefore, it is necessary to be able to effectively deal with resource failures which could endanger the SLAs by affecting the provided services. The effort for recovering from failures should be selected corresponding to the expected SLA violation costs. In this paper we present a framework to automatically determine the impact of resource failures with respect to services and service level agreements. We achieve this by monitoring the service quality from inside and outside the service provider and also by incorporating information about the current and expected future service usage. The expected costs of the resource failures are assessed to select an appropriate recovery alternative. Besides this short term perspective the impact analysis can also be employed to identify critical resources and to improve the service provisioning.

Assured service quality by improved fault management

The paradigm shift from device-oriented to service-oriented management has also implications to the area of event correlation. Todays event correlation mainly addresses the correlation of events as reported from management tools. However, a correlation of user trouble reports concerning services should also be performed. This is necessary to improve the resolution time and to reduce the effort for keeping the service agreements. We refer to such a type of correlation as service-oriented event correlation. The necessity to use this kind of event correlation is motivated in the paper. To introduce service-oriented event correlation for an IT service provider, an appropriate modeling of the correlation workflow and of the information is necessary. Therefore, we examine the process management frameworks IT Infrastructure Library (ITIL) and enhanced Telecom Operations Map (eTOM) for their contribution to the workflow modeling in this area. The different kinds of dependencies that we find in our general scenario are then used to develop a workflow for the service-oriented event correlation. The MNM Service Model, which is a generic model for IT service management proposed by the Munich Network Management (MNM) Team, is used to derive an appropriate information modeling. An example scenario, the Web Hosting Service of the Leibniz Supercomputing Center (LRZ), is used to demonstrate the application of service-oriented event correlation.

Integrated monitoring of multi-domain backbone connections Operational experience in the LHC optical private network

Novel large scale research projects often require cooperation between various different project partners that are spread among the entire world. They do not only need huge computing resources, but also a reliable network to operate on. The Large Hadron Collider (LHC) at CERN is a representative example for such a project. Its experiments result in a vast amount of data, which is interesting for researchers around the world. For transporting the data from CERN to 11 data processing and storage sites, an optical private network (OPN) has been constructed. As the experiment data is highly valuable, LHC defines very high requirements to the underlying network infrastructure. In order to fulfil those requirements, the connections have to be managed and monitored permanently. In this paper, we present the integrated monitoring solution developed for the LHCOPN. We first outline the requirements and show how they are met on the single network layers. After that, we describe, how those single measurements can be combined into an integrated view. We cover design concepts as well as tool implementation highlights.