OverQoS

Guaranteeing end-to-end quality-of-service with a generic routing approach

Quality-of-Service (QoS) provisioning plays a pivotal role in widespread deployment of new emerging services over the current Internet and is expected to be an indispensable attribute of future Internet. Though relevant progress has been made towards ensuring QoS, modeling and developing efficient algorithms for end-to-end QoS provisioning remain challenging problems in the current and future Internet infrastructure. In this paper, we address these challenging problems from a generic routing perspective, emphasizing modeling and algorithms as well as evaluation on end-to-end QoS provisioning. Specifically, we first model the common features of major technologies for end-to-end QoS provisioning in a "bottom-up" manner. Through the model, a set of end-to-end performance bounds that indicate the serving capability of substrates are obtained. Then we propose two routing algorithms based upon the model and performance bounds. The analysis on computational property of proposed algorithms proves that they are light-weighted and cost-effective. We also conduct thorough performance comparison between the proposed algorithms and previous best-known results in both theoretical and experimental ways. Our results show that the model and the algorithms developed in this paper are efficient and superior to other competitors, thus are applicable to the various networking systems for end-to-end QoS provisioning in current and future Internet.

Satellitelab

Planetary-scale network testbeds like PlanetLab and RON have become indispensable for evaluating prototypes of distributed systems under realistic Internet conditions. However, current testbeds lack the heterogeneity that characterizes the commercial Internet. For example, most testbed nodes are connected to well-provisioned research networks, whereas most Internet nodes are in edge networks.

In this paper, we present the design, implementation, and evaluation of SatelliteLab, a testbed that includes nodes from a diverse set of Internet edge networks. SatelliteLab has a two-tier architecture, in which well-provisioned nodes called planets form the core, and lightweight nodes called satellites connect to the planets from the periphery. The application code of an experiment runs on the planets, whereas the satellites only forward network traffic. Thus, the traffic is subjected to the network conditions of the satellites, which greatly improves the testbed's network heterogeneity. The separation of code execution and traffic forwarding enables satellites to remain lightweight, which lowers the barrier to entry for Internet edge nodes.

Our prototype of SatelliteLab uses PlanetLab nodes as planets and a set of 32 volunteered satellites with diverse network characteristics. These satellites consist of desktops, laptops, and handhelds connected to the Internet via cable, DSL, ISDN, Wi-Fi, Bluetooth, and cellular links. We evaluate SatelliteLab's design, and we demonstrate the benefits of evaluating applications on SatelliteLab.