Jyoti Parwatikar

The open network laboratory

The Open Network Laboratory (ONL) is a remotely accessible network testbed of high performance routers which has been designed with an eye towards ease of use for users from the naïve to the expert. The system is built around a set of high-performance routers that are extendible and easily configurable through the Remote Laboratory Interface (RLI), an intuitive graphical interface. The RLI also makes it easy to configure packet filters in the routers, assign flows or flow aggregates to separate queues with configurable QoS and attach hardware monitoring points to real-time charts. The RLIs real-time charts and user data facility make it easy to directly view the effects of traffic as it moves through a router, allowing the user to gain better insight into system behavior and create compelling demonstrations. Each port of the router is equipped with an embedded processor that supports software plugins which allow users to extend the systems functionality. This paper describes the ONL and how it can be used in networking education. Our web site onl.arl.wustl.edu includes a short video and a tutorial.

Online Scheduling with Hard Deadlines

We study non-preemptive, online admission control in the hard deadline model: each job must either be serviced prior to its deadline or be rejected. Our setting consists of a single resource that services an online sequence of jobs; each job has a length indicating the length of time for which it needs the resource and a delay indicating the maximum time it can wait for the service to be started. The goal is to maximize total resource utilization. The jobs are non-preemptive and exclusive, meaning once a job begins, it runs to completion, and at most one job can use the resource at any time. We obtain a series of results, under varying assumptions of job lengths and delays.

Distributed queueing in scalable high performance routers

This paper presents and evaluates distributed queueing algorithms for regulating the flow of traffic through large, high performance routers. Distributed queueing has a similar objective to crossbar-scheduling mechanisms used in routers with relatively small port counts, and shares some common high level characteristics. However, the need to minimize communication overhead rules out the iterative methods that are typically used for crossbar scheduling, while the ability to sub-divide the available bandwidth among different ports provides a degree of freedom that is absent in the crossbar scheduling context, where inputs must be matched to outputs. Our algorithms are based on four ideas (1) backlog-proportional-allocation of output bandwidth, (2) urgency-proportional-allocation of input bandwidth, (3) dynamic reallocation of bandwidth and (4) deferred underflow. Our algorithms guarantee congestion-free operation of the switch fabric. Our performance results show that for uniform random traffic, even a very modest speedup is sufficient to reduce the loss of output link bandwidth due to sub-optimal rate allocation to negligible levels, and that even under extreme conditions, a speedup of two is sufficient to eliminate such bandwidth loss.

Design and evaluation of a high-performance dynamically extensible router

This paper describes the design, implementation and performance of an open, high performance, dynamically extensible router under development at Washington University in St. Louis. This router supports the dynamic installation of software and hardware plug-ins in the data path of application data flows. It provides an experimental platform for research on programmable networks, protocols, router software and hardware design, network management, quality of service and advanced applications. It is designed to be flexible without sacrificing performance. It supports gigabit links and uses a scalable architecture suitable for supporting hundreds or even thousands of links. The systems flexibility makes it an ideal platform for experimental research on dynamically extensible networks that implement higher level functions in direct support of individual application sessions.

On-line scheduling with hard deadlines

We study non-preemptive, online admission control in the hard deadline model: each job must be either serviced prior to its deadline, or be rejected. Our setting consists of a single resource that services an online sequence of jobs; each job has a length indicating the length of time for which it needs the resource, and a delay indicating the maximum time it can wait for the service to be started. The goal is to maximize total resource utilization. We obtain a series of results, under varying assumptions of job lengths and delays.

The open network laboratory: a resource for networking research and education

The Open Network Laboratory (ONL) is a remotely accessible network testbed designed to enable networking faculty, students and researchers to conduct experiments using high performance routers and applications. The system is built around a set of extensible, high-performance routers and has a graphical interface that enables users to easily configure and run experiments remotely. ONLs Remote Laboratory Interface (RLI) allows users to easily configure a network topology, configure routes and packet filters in the routers, assign flows or flow aggregates to separate queues with configurable QoS and attach hardware monitoring points to real-time charts. The remote visualization features of the RLI make it easy to directly view the effects of traffic as it moves through a router, allowing the user to gain better insight into system behavior and create compelling demonstrations. Each port of the router is equipped with an embedded processor that provides a simple environment for software plugins allowing users to extend the systems functionality. This paper describes the general facilties and some networking experiments that can be carried out. We hope that you and your collegues and students will check out the facility and register for an account at our web site <u>onl.arl.wustl.edu</u>

Vaudeville: A High Performance, Voice Activated TeleconferencingApplication

We present Vaudeville, a voice-activated, hands-free, ATM-based video conferencing application. This system is scalable; although video bandwidth is normally a limiting factor in the number of conferences participants, the bandwidth attributed to the video is not a function of conference size. This is achieved through an automatic, distributed floor control mechanism that gives the appearance of an open floor. Audio and video are encoded in hardware using a platform-independent, ATM hardware multimedia interface. Vaudeville features digitally transmitted NTSC video, voice-activated audio transmission, audio bridging of two audio streams, and voice-activated video switching. Multiple simultaneous multiparty conferences are supported. Users can move freely among conferences without knowledge of the underlying network structure. We describe how Vaudeville was built using a component-based distributed programming environment. We also describe the algorithms used to control the audio and video of the application.

Implementation of an Open Multi-Service Router

This paper describes the design, implementation and performance of an open, highperformance, dynamically reconfigurable Multi-Service Router (MSR) being developed at Washington University in St. Louis. This router provides an experimental platform for research on protocols, router software and hardware design, network management, quality of service and advanced applications. The MSR has been designed to be flexible, without sacrificing performance. It supports gigabit links and uses a scalable architecture suitable for supporting hundreds or even thousands of links. The MSR’s flexibility makes it an ideal platform for experimental research on dynamically extensible networks that implement higher level functions in direct support of individual application sessions. This work was supported in part by NSF grants ANI-0096052, ANI-9714698, ANI-9813723, ANI-9616754 and DARPA grant N66001-98-C-8510. Implementation of an Open Multi-Service Router Fred Kuhns , John DeHart , Ralph Keller , John Lockwood , Prashanth Pappu , Jyoti Parwatikar , Ed Spitznagel , David Richards , David Taylor , Jon Turner and Ken Wong fredk,jdd,keller, lockwood,prashant,jp,ews1,wdr,det3,jst,kenw @arl.wustl.edu Department of Computer Science and the Applied Research Laboratory Department of Electrical Engineering and the Applied Research Laboratory Washington University, St. Louis, MO 63130, USA

Experiments with the Emulated NDN Testbed in ONL

Named Data Networking (NDN) is a recently proposed information-centric network architecture. The NDN Testbed is a global infrastructure that enables real-world NDN demonstrations. However, deploying new applications directly on the NDN Testbed requires considerable operational support and may introduce instability to shared testbed infrastructure. Whats more, network performance parameters cannot be easily modified on the NDN Testbed to study application behaviors. As a result, an emulated NDN testbed, and one over which developers have full control, can benefit testing, debugging, and evaluating new NDN applications and services as a complement and precursor to testbed deployment. In this demonstration, we present the emulated NDN testbed that runs in the Open Network Laboratory (ONL). The emulated testbed runs on real servers (there is no simulation) and uses the same NDN forwarding daemon, NFD, and the same routing software, NLSR, that are used in the NDN Testbed; this minimizes the efforts required of developers to evaluate their applications. We show how the flexibility of ONL enables the study of application behaviors in varying network environments and conditions. We also use a data collection application to demonstrate the effectiveness of using the emulated testbed to support application development.

Design of an Extensible Network Testbed

Networking testbeds have become an increasingly important part of the networking research cycle. One of the primary reasons for this is that testbeds offer researchers access to network conditions and environments which are very difficult to reproduce in a local laboratory. This work presents the design of the Open Network Laboratory (ONL) testbed. The underlying infrastructure of ONL is general enough to support resource extensibility and heterogeneity at a fundamental level. New types of resources (e.g., multicore PCs, FPGAs, network processors, etc) can be added to the testbed without modifying any testbed infrastructure software. Resource types can also be extended to support multiple distinct sets of functionality (e.g., an FPGA might act as a router, a switch, or a traffic generator). Moreover, users can dynamically add new resource extensions without any modification to the existing infrastructure.