Chapter 28 Inter-Domain SLA Enforcement in QoS-Enabled Networks C. Marinos, V. Pouli, M.Grammatikou, and V. Maglaris Abstract Traditionally, network Service Providers specify Service Level Agree- ments (SLAs) in order to guarantee service availability and performance to their customers. However, these SLAs are rather static and span a single provider domain. Thus, they are not applicable to a multi-domain environment (including edge net- works of distributed Grid resources) and do not enable users with the flexibility to set up and monitor e2e services. In this chapter we present a framework for dynamic management of SLAs; the framework contains a collection of APIs and modules that allow for the dynamic creation, configuration, and delivery via automated manage- ment of an end-to-end SLA created from the merging of the per-domain SLAs. We assume that individual domains are QoS aware, since near real-time applications (e.g., IP voice and video sessions and Grids for remote control of sensors – instru- ments) may impose stringent performance requirements, even on over-engineered backbone and edge networks. Keywords Service Level Agreement (SLA) · Multi-domain · SLA Framework · QoS · Inter-domain · Intra-domain 1 Introduction A Service Level Agreement (SLA) is a contract between a network provider and a customer defining all aspects of the service offered. It may specify the levels of availability, serviceability, performance, and operation conditions [7, 12]. It may also define the procedures and the reports that must be provided to track and ensure compliance with the SLA or describe other attributes of the service, such as billing and penalties in case of SLA violations [2]. C. Marinos (B) Network Management and Optimal Design Lab. (NETMODE), National Technical University of Athens, Iroon Polytexniou 9, 15780 Zografou, Greece e-mail: cmarinos@netmode.ntua.gr F. Davoli et al. (eds.), Remote Instrumentation and Virtual Laboratories, DOI 10.1007/978-1-4419-5597-5_28, C  Springer Science+Business Media, LLC 2010 351