A Trial Deployment of a Reliable Network-Multicast Application across Internet2

Abstract

A continuing trend in many scientific disciplines is the growth in the volume of data collected by scientific instruments and the desire to rapidly and efficiently distribute this data to the scientific community. Transferring these large data sets to a geographically distributed research community consumes significant network bandwidth. As both the data volume and number of subscribers grows, reliable network multicast is a promising approach to reduce the rate of growth of the bandwidth needed to support efficient data distribution. In prior work, we identified a need for reliable network multicast: scientists engaged in atmospheric research subscribing to meteorological file-streams. Specifically, the University Cooperation Atmospheric Research (UCAR) uses the Local Data Manager (LDM) to disseminate data. This work describes a trial deployment of a multicast-enabled LDM, in which eight university campuses are connected via corresponding regional Research-and-Education Networks (RENs) and Internet2. Using this deployment, we evaluated the new version of LDM, LDM7, which uses network multicast with a reliable transport protocol, and leverages Layer-2 (L2) multipoint Virtual LAN (VLANIMPLS). A performance monitoring system was deployed to collect real-time performance of LDM7, which showed that our proof-of-concept prototype worked significantly better than the current production LDM, LDM6, in two ways: (i) LDM7 can distribute file streams faster than LDM6. With six subscribers, an almost 22-fold improvement was observed with LDM7 at 100 Mbps. And (ii) to achieve a similar performance, LDM7 significantly reduces the need for bandwidth, which reduced the bandwidth requirement by about 90% over LDM6 to achieve 20 Mbps average throughput across four subscribers.