Erik Nygren

The Akamai network: a platform for high-performance internet applications

Comprising more than 61,000 servers located across nearly 1,000 networks in 70 countries worldwide, the Akamai platform delivers hundreds of billions of Internet interactions daily, helping thousands of enterprises boost the performance and reliability of their Internet applications. In this paper, we give an overview of the components and capabilities of this large-scale distributed computing platform, and offer some insight into its architecture, design principles, operation, and management.

PAN: a high-performance active network node supporting multiple mobile code systems

A capsule-based active network transports capsules containing code to be executed on network nodes through which they pass. Active networks facilitate the deployment of new protocols, which can be used without any changes to the underlying network infrastructure. This paper describes the design, implementation, and evaluation of a high-performance active network node which supports multiple mobile code systems. Experiments, using capsules executing unsafe native Intel ix86 object code, indicate that active networks may be able to provide significant flexibility relative to traditional networks with only a small performance overhead (as little as 13% for 1500 byte packets). However, capsules executing JavaVM code performed far worse (with over three times the performance overhead of native code for 128 byte packets), indicating that mobile code system performance is critical to overall node performance.

VEVI: A Virtual Environment Teleoperations Interface for Planetary Exploration

Remotely operating complex robotic mechanisms in unstructured natural environments is difficult at best. When the communications time delay is large, as for a Mars exploration rover operated from Earth, the difficulties become enormous. Conventional approaches, such as rate control of the rover actuators, are too inefficient and risky. The Intelligent Mechanisms Laboratory at the NASA Ames Research Center has developed over the past four years an architecture for operating science exploration robots in the presence of large communications time delays. The operator interface of this system is called the Virtual Environment Vehicle Interface (VEVI), and draws heavily on Virtual Environment (or Virtual Reality) technology. This paper describes the current operational version of VEVI, which we refer to as version 2.0. In this paper we will describe the VEVI design philosophy and implementation, and will describe some past examples of its use in field science exploration missions.

Operator Interfaces and Network-Based Participation for Dante II

Dante II, an eight-legged walking robot developed by the Dante project, explored the active volcanic crater of Mount Spurr in July 1994. In this paper, we describe the operator interfaces and the network-based participation methods used during the Dante II mission. Both virtual environment and multi-modal operator interfaces provided mission support for supervised control of Dante II. Network-based participation methods including message communications, satellite transmission, and a WorldWideWeb server enabled remote science and public interaction. We believe that these human-machine interfaces represent a significant advance in robotic technologies for exploration.

Networked systems research at Akamai

In this special section of OSR, we present a selection of research papers that relate to Akamais platform and technology.