DOE engineers help pioneer multi-network traffic monitor

A consortium of academic and federal lab engineers are building a framework and an associated set of software tools that can monitor the how efficiently data moves across multiple networks, called Performance Service Oriented Network (perfSONAR).

Internet2 network engineer and perfSONAR co-developer Richard Carlson presented the framework at the Collaborative Expedition Workshop, held yesterday in Arlington, Va.

While many IT products are available to monitor, and analyze traffic patterns on a single network, not many tools exist for analyzing traffic that flows across multiple networks. Yet, most data traffic that federal researchers transverses multiple networks. "There is not one institution that owns the entire path," Carlson said. An implementation of perfSONAR could provide a uniform picture of how data moves across all the networks.

The work is timely. This year, the Energy Department labs will start to receive massive data sets from the Large Hadron Collider particle accelerator, operated by the European Organization for Nuclear Research. So the challenge of figuring out where traffic is slowing down on the network will only become more of an issue in the years to come.

Carlson noted that, today, federal researchers should be able to move data across multiple research networks at about 10 megabytes per second. Today, however, most data transfers travel an order of magnitude or lower than that.

A researcher who is interested in how quickly his or her dataset snakes its way through this maze of networks can find performance information today, but he has to know who to call, and which Web address to check, Carlson said. perfSONAR would allow them to pinpoint where the bottlenecks are. With perfSONAR, "you can find out what is going on in a path without any prior knowledge" of the network analysis resources, Carlson said.

perfSONAR allows a someone to gather the data from all the networks in a uniform way, allowing the individual to quickly pinpoint where the weak spot is.

In this setup, each network, or domain, would host a copy of the perfSONAR toolset on a server. The perfSONAR framework uses existing network monitoring protocols, such as the Simple Network Management Protocol (SNMP) to collect performance stats. An ideal setup would archive performance history, so a comparative analysis could be done. The software package would also include a set of Web services that would allow external users of the network, or others, to check the performance.

The framework consists of three inter-related sets of technologies: One is is set of tools for data services, including measurement points, procedures for archiving and for transforming the data. The second provides analysis and visualization tools, including user Graphic User Interfaces, Web pages and network operation center alarms. The third group of technologies is for seeding perfSONAR into the infrastructure, including a service lookup client and a way to create a topology of the network.

Carlson noted that perfSONAR does not take any additional network measurements. Rather, it packages existing network measurements and makes them uniformly available for users. He offered an example of one perfSONAR application Traceroute Visualizer, created by Joe Metzger. It uses the data taken from the traceroute utility, a commonly-used tool for mapping out each node along a network. With Traceroute Visualizer, you provide the results of a traceroute to the Web interface, and it shows a history of each node's performance.

perfSONAR is being developed as a collaboration between network engineers from the Energy Department's Energy Sciences Network, the Internet2, the European GÉANT2 research network and the Brazilian Rede Nacional de Ensino e Pesquisa network.

The development team created two reference implementations of the framework, on written in Java and one written in Perl. The perfSONAR toolkit is also available on a live disc. perfSONAR was developed through the Open Grid Forum, a standards body for grid technologies, so the basic specifications written in Extensible Markup Language (XML), allowing other parties to build their own perfSONAR implementations.

Carlson said that the goal of the team was to get perfSONAR installed on every network run by a Federal lab. Each network operator, Carlson admitted, would have to consider what level of openness they would want to provide. He did note that the development team still had to work out how to provide user-authentication. In particular, they are looking at the Internet2's Shibboleth model for authentication.

Attendees of the workshop added that other standards bodies are working on similar frameworks that can help monitor data flow across multiple networks. For instance, the Distributed Management Task Force is working on Web Service-Management (WS-Management), and the Organization for the Advancement of Structured Information Standards is working on Web Services Distributed Management (WSDM).

Domain-specific data sharing standards are also cropping up. The National Science Foundation (NSF) has funded a hydrological data-sharing initiative called the Consortium of Universities for the Advancement of Hydrologic Science (CUAHSI). The Environmental Protection Agency and the Agriculture Department both participate in this initiative. One of of the components of this initiative is the CUAHSI Hydrologic Information System (CUAHSI-HIS), which provides Web services, tools, standards and procedures for data sharing.

The Collaborative Expedition Workshop is sponsored by the General Services Administration's Intergovernmental Solutions Division, the Federal Chief Information Officer Council's Architecture and Infrastructure Committee and the National Coordination Office of the Interagency Committee on IT research and development.