Traffic Microbursts and their Effect on Internet Measurement
In August 2015, M-Lab was notified of potential degradation of site performance by a measurement partner based on discrepancies compared to results for their own servers. After a full investigation these patterns were found to have been caused by the unique confluence of several specific conditions. Interim remediation measures were taken in early October 2015, and the resolution of the degradation was confirmed by the partner and others. Due to these administrative actions, the episode, which we are calling the “switch discard issue,” has not affected testing conducted in the United States (the region impacted by this problem) since October 11, 2015, and thus measurements after this period are not affected by the incident. M-Lab has also conducted an evaluation of data collected during the time period in which the issue occurred, and has taken steps to remove affected measurements from its dataset. This incident will not affect use of its dataset, past or present, as a result.
Making it Easier to Use M-Lab Data
In January, M-Lab launched a beta test of new BigQuery tables for M-Lab data. Today, M-Lab is pleased to announce that the beta test was successful. The new, faster-performing tables will be M-Lab’s new standard BigQuery tables.
Before we move on to specifics, when we say faster performing, we mean a lot faster. As in, certain queries that used to take over 2 hours now complete in 8 seconds. That means that playing with the data just became a lot more fun.
To help users dig in to this data as quickly and seamlessly as possible, M-Lab has consolidated all of its data documentation and updated it to show how to take advantage of the new tables.
New Opportunities for Test Deployment and Continued Analysis of Interconnection Performance
In late April, Internet2, with contributions from M-Lab developers, released an updated version of the Network Diagnostic Tool (NDT), M-Lab’s most widely deployed performance measurement test. In addition to improved stability, the updated version of NDT makes it possible to measure network performance from a web browser without the need for browser plugins. This change removes a layer of complexity and hassle for developers and users. Anyone interested in Internet measurement can now create their own NDT client targeted for specific user populations, regions, and research objectives, using only HTML and Javascript.
Data Duplication Bug in M-Lab BigQuery Data
The team working on archiving M-Lab data recently discovered that the M-Lab data hosted in BigQuery was affected by a bug that caused duplicates to appear in our dataset. Queries against M-Lab’s BigQuery dataset performed between May 2014 and April 2015 were impacted. The raw files in our Google Cloud Storage bucket were not.