1. 1 Campus QoS- Bandwidth Ain’t Enough Willis Marti Texas A&M University

2. April 10, 2002 Texas A&M 2 Search for Eldorado Need for QoS? Why a Campus Focus? Approaches & Difficulties Solutions & More Problems Futures Summary

3. April 10, 2002 Texas A&M 3 Need for QoS? VoIP, Videoconferencing … Realtime, Interactive Applications Need Help Best-effort not enough Buffer management no solution (all arguable … but we need something)

4. April 10, 2002 Texas A&M 4 Why a Campus Focus Something we can control Largest part of problem Use (hope for) “law of aggregates” for off-campus links

5. April 10, 2002 Texas A&M 5 Approaches … Throw Bandwidth at Problems Build Separate Networks Different ‘wires’ VLANs QoS ATM IP {RSVP, Diff-Serv, Bandwidth Broker} Hope

6. April 10, 2002 Texas A&M 6 … and Difficulties “Hope” Network managers are realistic pessimists. Most QoS is unmanageable or doesn’t scale Separate network(s) too costly Bandwidth Ain’t Enough

7. April 10, 2002 Texas A&M 7 The Whole Path L2 L3 L2

8. April 10, 2002 Texas A&M 8 Bandwidth Ain’t Enough Need Layer 2, 3 integrated scheme Microcongestion … Whole path treatment Vs end-to-end Management tools not there

9. April 10, 2002 Texas A&M 9 Solutions Incremental Deployment TOS, 802.1p Diff-Serv as superset Priority Queues S.E.E.D. (Service Enabled Edge Devices) Marking Number of queues Authentication?

10. April 10, 2002 Texas A&M 10 TOS interpretations 7 – network control 6 5 - voice 4 - video 3 2 – “normal” ? 1 0 – “normal” ?

11. April 10, 2002 Texas A&M 11 More Problems (some) When does 3 bits mean 8 choices? Video classrooms vs JennyCam Management

12. April 10, 2002 Texas A&M 12 Queue Effects Eight 7 – network control 6 5 - voice 4 - video 3 2 – “normal” ? 1 0 – “normal” ? Four 7/6 5/4 3/2 1/0 Two High Low

13. April 10, 2002 Texas A&M 13 Futures Dynamic Marking Rules Per user Per Application Call Admission Inter-Domain Requests

14. April 10, 2002 Texas A&M 14 Summary Plug ‘n’ Pray But learning opportunities abound!