Status Report for SLAC/DOE IEPM Project

For March 2002

SLAC Home Page
Work completed or in progress since the last report.

Work Related to Analysis and Development


Warren debugged the way the analysis deals with corrupted entries resulting in nonsense nodes.


Les, Connie and Manish worked to try and understand the passive vs. active bandwidth measurements, see Correlation Table for Active and Passive Monitoring.


SLAC hosted a visting PhD student from the Rice/INCITE project and worked with her to calrify the needs for tomography and topology. Warren worked with Yolanda Tsang from Rice to understand IP tunneling for the INCITE project. We had a phone meeting with the INCITE folks.


More software installation with Allen from Telcordia. Warren & Les had a phone meeting with Telcordia folks to understand the privacy and security measures built into the Telcordia probe that we wish to deploy on the visitors subnet. We followed up with several emails and then wrote a request to the SLAC security folks and management formally requesting to install the probe and start measurements.


Warren is working with Adil Hasan and our collaborators to enable DOE SG certificates. BNL and ANL are intending to use them, but have not declared when.


Warren talked with the administrator at DESY on their plans for VoIP. Les helped someone from NetPredict with understanding the effect of delay on Mean opportunity Scores as a function of compression type.


Warren re-installed web100 on antonia & hercules and explained to Les how to get at the data. Les added Web100 variable recording to his TCP windows and streams measurement script.


Les worked with John Halperin to write a doument on what to do when traceroute intermittently fails to resolve a name.
Les followed up on 4 false port scan reports. He then modified to try and ensure novices read the warning about traceroute looking like a port scan, see He also blocked access to the traceroute server from 4 hosts which were sending many requests in a burst each hour, which causes the traceroute queue to overflow. Had previously tried to contact the security, postmaster, abuse, root addresses on these hosts.

Tool evaluation

Les updated the network management tools page.
Les and Connie did a rough analysis of the effectiveness of pipechar compared to iperf, see Pipechar predictions of bandwidth.
Jiri and Les worked on evaluating a new network estimation program from LBNL, called netest.

Trouble shooting

Les worked with IN2P3, ESnet and others to resolve some problems with the IN2P3 link via Renater. The link has now been upgraded to 100Mbps but the ESnet connection is limited to 30Mbps, see case study.
Les worked on iperf throughput from SLAC to DL and RAL and improved the latter quite dramatically by increasing window sizes at RAL, see case study.
Les responded to a report of poor performance between SLAC and INFN/Rome, see the case study

Missing Data

Still no data from BNL nor INFN. A little trouble this month with gathering data from NBI and Wisc due to technical issues at those sites.


The usual paperwork, installations and administration.

Work related to Publicity and Information


Les, Warren, & Connie submitted a paper to IEEE on the performance measurement results.


Warren created a few slides on the IPEX project for a DoE visit.


Warren attended a Project Management course and 'Building Cisco Remote Access Networks (BCRAN)'.

Travel & Talks

Les visited Daresbury and CERN, see trip report trip report. He gave a talk at the CERN ICFA/SCIC meeting.
Les prepared and gave an invited talk on IEPM-BW at the Institute for Pure & Applied mathematics at UCLA.


Thomas Ndousse visited SLAC so we spent most of the day with him with presentations, and discussions including Connie, Jiri, Yo Yo and Richard.


We are working with Caltech to gear up for attempt on the Internet land speed record.

Created March 24, 2002, last update April 4 2002.
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