1. Performance Measurements in Internet2 Guy Almes Geneve – 15 March 2004

2. CERN: 15-Mar-04 2 Outline  Infrastructure Observations  Software Observations  The Measurements  Putting it all together

3. CERN: 15-Mar-04 3 Infrastructure Observations  From 1983 to the present, we have partial meshes and growth in b/s rates: 1983: 50 kb/s ARPAnet 1988: 1.5 Mb/s NSFnet 1992: 45 Mb/s NSFnet 1995: 155 Mb/s vBNS => 622 Mb/s 1998: 2.4 Gb/s Abilene => 9.6 Gb/s  But this rapid growth is now stopping either stopping at 10 Gb/s or perhaps merely slowed growth

4. CERN: 15-Mar-04 4

5. 5 Abilene Backbone Network

6. CERN: 15-Mar-04 6  The partial-mesh with growing b/s rates approach is now ending  Several new approaches are promising: fuller mesh (=> fewer hops) dynamic mesh – adaptive based on measurements – scheduled by users or on-demand larger MTUs focus on effective file transfer  These will be interesting times

7. CERN: 15-Mar-04 7  Implications of these new styles Exciting ideas to be created, tested, deployed Uncertainty with regard to future end-states Turmoil during transition from present to future  Increasing holistic attitude to networking from 'my part works' to 'ensure system works end to end'

8. CERN: 15-Mar-04 8 Software Observations  Evolution of TCP control algorithms 1986-1992: dramatic improvement – basis for effective use of wide-area 1.5 Mb/s networks 1992-2002: relative neglect – while wide-area networks grew to 2.5 Gb/s since about 2003: renewed research vigor – FAST – HS-TCP – Other very good work at Cambridge, Hamilton, North Carolina State, Rice, Univ Illinois Chicago  Uncertainty  Turmoil

9. CERN: 15-Mar-04 9 The Measurements  Items to be measured TCP throughput one-way delay (and round-trip) variation in delay packet loss increasingly relevant  Active and passive  Relationship to security trends

10. CERN: 15-Mar-04 10  Separate applications of compatible measurements within core of a given network (within core) aggregated sets of networks (extended core?) between file servers of a given grid (edge to edge) from grid site to core (edge to core)  Technical accuracy of great importance  Reporting: focusing on near-worst-case think about performance that is almost always delivered supports taking a quality control attitude at several layers

11. CERN: 15-Mar-04 11

12. CERN: 15-Mar-04 12 Putting it all Together  User communities are learning to quantify their requirements  Networks then accept the challenge (or not)  Network groups measure their networks  User groups measure delivered performance  Mutual accountability and support

13. CERN: 15-Mar-04 13