Design of QoS Router

1. Design of QoS Router Terrance Lee

2. Access Network Access Network Core Network Access Network Access Network Optimized for speed Packet over Sonet (Diffserv) (IP/PPP/Sonet/DWDM) All Optical Network (MPLS)  Broadband Internet Architecture Content Provider • Intelligent Access • Electronic Switch • (Intserv or Diffserv) • Switching /Routing • QoS • Security

3. Core Network • Optical Switch • Cache Server for Content Providers • Label Distribution • Traffic Engineering

4. Access Network • Cache Server for Content Providers • QoS Router - Control Plane QoS Routing RSVP Admission Control - Data Plane QoS Mechanisms Measurements Switch Fabric - Management Plane QoS Service Management

5. Admission Control • Bandwidth allocation in access networks • Heavily depends on the adopted service scheduling algorithm (e.g., WFQ, Rate Monotonic) • Trade off between complexity and utilization

6. QoS Mechanisms • Packet Classifier • Meter • Marker • Dropper • Queue Manager • Shaper • Scheduler

7. Network Planning QoS Service Management Management Control RSVP QoS Routing Admission Control Memory Search Engine Memory Data P H Y M A C Frame Engine Packet Classifier Meter Marker Dropper Queue Manager QoS Measurement Switch Fabric or MAC Shaper/Scheduler Memory

8. Packet Classifier • Purposes - QoS Guarantee - Security - Billing - etc.

9. Packet Classifier • Behavior Aggregate • IPv4 Multi-Field-5 • IPv4-Multi-Field-6 • IEEE 802 MAC • IEEE 802.1p • IEEE 802.1q • IPv6 Multi-Field-5 • IPv6 Multi-Field-6 • Free Form

10. Packet Classifier • Hash Bucket • 64 Rules • Src and Dest IP Addresses: Prefix Match • Src and Dest Port Numbers: Range Match • Protocol ID: Exact Match • 20 Bytes/Rule (Include Valid Time Period and Output) • Memory Size: ~ 4K Bytes • Wire Speed Classification: ~ 5 Mpps (32-bit Bus @ 100MHz) (4 Reads)

11. Meter • Average Rate Meter Parameters: average rate, delta interval • EWMA Meter Parameters: average rate, delta interval, gain • Token Bucket Meter (srTCM, trTCM) Parameters: CIR, PIR, CBS, PBS, EBS

12. Meter • 64 Token Bucket Entries • Memory Size: ~ 256Bytes • Stored Parameters: Bucket Size, Bucket Occupancy, Leaky Rate, Scaling Factor • Wire Speed Metering: ~ 5 Mpps (32-bit Bus @100MHz) (3 Reads, 1 Write)

13. Marker • An Optional Service • When TRUE, Remark the Attribute Field for All Traffic • When FALSE, Remark Only Unmarked Traffic • Attribute Field TOS Byte DSCP Field IEEE 802.1p Priority Field Proprietary (User Defined)

14. Marker • 4 Priority Queues • 3 Levels of Drop Precedence

15. Dropper • Drop from Head • Drop from Tail • RED • WRED • FRED • Always Drop • User Defined

16. Criteria for Dropping • Queue Threshold • Arrival Rate • Other

17. Drop Metric • IP Precedence • DSCP Value • IEEE 802.1p Priority Value • RSVP Session • Queue Depth • Packet Arrival Rate • Other

18. Scheduler • FIFO (First In First Out) • SP (Strict Priority) • WFQ (Weighted Fair Queuing) • SP/WFQ • WRR (Weighted Round Robin) • Priority Bandwidth (Priority with Maximum Burst Constraint)

19. Scheduler • Configurable Number of Queues under Strict Priority • Weights of WFQ: 0-63 • Up to 4 Queues

20. Shaper • An Optional Service • Per-Class Token Bucket Traffic Shaping • srTC and trTC shaping • SLA Guarantee • When Enabled, Service Becomes Non-Work-Conserving

21. Summary • We Prototyped a Router with Complete QoS Mechanisms • Future Work: IPSec, MPLS Capability