A perfSONAR User's Group

Little Boxes In The Internet Monitoring Biz

Over the last decade and a half, I often paused to wonder about using small computers for network assessment. The market seemed to be made up of exciting press releases about product that no retailer had in stock, or if they did, there was a prohibitive minimum quantity for purchase. Less than two years ago, […]

Switch buffer size

I gave a lightning talk in 2010 at Joint Techs that reviewed measurements that show empirically how buffer size affects bwctl throughput. I partitioned the buffer RAM on a Catalyst 6500 Gig-E port to different queues. I set the RED parameters to get pure tail drop performance. The bwctl tests were done to the best […]

Iperf “self-tests”

From a performance-node-users@internet2.edu thread: https://lists.internet2.edu/sympa/arc/performance-node-users/2013-05/msg00048.html Answer from Ezra Kissel at I.U. , which illuminates some things perhaps relevant to understanding throughput and tester validation. My original question: What is the value or meaning of results from a “self test”, as would occur when one runs an iperf server on a host, and then runs the client […]

NPAD Tweaks

Someday I would like to do a post or page here which ties NPAD/pathdiag up into a neat, comprehensible package. I think that it is probably one of the most useful, least understood parts of perfSONAR, as it offers diagnostics that cannot be found elsewhere. If you want to get a good look an close-in […]

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