Connect Communicate Collaborate PERT Performance Enhancement Response Team

Connect. Communicate. Collaborate PERT Performance Enhancement & Response Team Toby Rodwell, DANTE Joint Techs, New Mexico USA 7 February 2006

Agenda • • • Background PERT Organisation PERT Systems Experience to date The future for the PERT Connect. Communicate. Collaborate

Motivation Connect. Communicate. Collaborate • Historically, long distance circuits (the “wide-area”) have been the bottleneck in a network • In recent years, the capacity of long distance circuits has significantly increased • End-to-end performance bottle-necks may now occur at any point in a system – end-system (application, OS, hardware), LAN or WAN • As such, it is becoming more and more difficult for a non-expert end-user to diagnose their network performance issues

Origins of the PERT Connect. Communicate. Collaborate • Conception of the PERT … Jan 01 Internet 2 Meeting – A support structure to investigate and resolve problems in the performance of applications over computer networks – Comparable to CERT structure • Realization of the PERT … Dec 2002 TERENA meeting – 6 European NRENs (GARR, SWITCH, CESnet, HEAnet and UKERNA) and DANTE committed to a practical trial of a basic PERT

The PERT Today Connect. Communicate. Collaborate • Permanently staffed (8 x 5) – CARNET, CESNET, FCCN, GARR, HUNGARNET, PSNC, RENATER, SWITCH • PERT Ticket System (PTS) • PERT Knowledgebase (PERT-KB) • PERT documentation – PERT Troubleshooting Guide – Performance User Guide and Best Practice Guide

PERT Organization Connect. Communicate. Collaborate • PERT Managers – Toby Rodwell (DANTE), Simon Leinen (SWITCH) • Case Managers – Duty Case Managers (weekly changing) – Special Case Managers • Subject Matter Experts – Unfunded volunteers – From NRENs, academia and industry – Work on an ‘as and when’ basis

PERT Systems Connect. Communicate. Collaborate • PERT Knowledgebase (PERT KB) – http: //pace. geant 2. net/cgi-bin/twiki/view/PERTKB/Web. Home – Updated on an ongoing basis • PERT Ticket System (PTS) – https: //www. pert. geant 2. net/pert/welcome. do – Currently Version 1 – Design of Version 2 about to start

Experiences to date Connect. Communicate. Collaborate • Low number of PERT cases – Plan to open up access to the PERT • Most of these concerned with low throughput over large BDP (Bandwidth Delay Product) paths – Often US to Europe – Even packet loss of 0. 002% has significant impact

General Findings Connect. Communicate. Collaborate • For long distance, high data rate transfers – Default TCP settings insufficient (buffers too small) – Jumbo packets are important (GEANT (and now GEANT 2) promoting the Abilene recommendation of 9000 byte IP packets) • Other common performance problem – Mismatched Ethernet duplex settings – (Not seen so far by GN 2 PERT, but a known problem)

The Future of the PERT Connect. Communicate. Collaborate • Involve more volunteer Subject Matter Experts • Gain more experience – Investigating more cases – Using new tools (perf. SONAR) • Disseminate the lessons learned • Promote the PERT as a NOC function • Disestablish the centralised PERT

Connect. Communicate. Collaborate Any Questions? Toby Rodwell, DANTE

Contacting the PERT Connect. Communicate. Collaborate • To date, only authorised Primary customers are able to submit a request for help – Primary Customers are NRENS and some pan. European projects • The PERT has recommended that access be widened to allow anyone to submit a case (the DCM would filter and prioritise requests) – Under consideration

Case Managers Connect. Communicate. Collaborate • Special Case Managers (SCMs) – For complex or drawn out cases a Special Case Manager (SCM) will take over and manage a case through to its closure – Work on a ‘best efforts’ basis • Duty Case Managers – Weekly-changing – Receive requests, assess eligibility, open new cases, set priorities and start investigations – Responsible for progressing all cases without an SCM, or where the SCM is unavailable