QOS-ENABLED NETWORKS - TOOLS AND FOUNDATIONS

"This is the first book about QOS that I actually enjoyed reading precisely because the authors focused on real-life QoS and not in academic discussions about it."
Per Nihlen, IP Network Manager, NORDUnet

The new authoritative, practical guide to delivering QOS guarantees

This new benchmark in quality of service (QOS) study is written by two experts in the field who deal with QOS predicaments every day. The authors not only provide a lucid understanding of modern theory of QOS mechanisms in packet networks but how to apply them in practice. In addition, they detail the QOS management features found in modern routers used by Internet Service Providers (ISPs) and large enterprise companies and networks, all in an effort to enable network managers and engineers to configure production networks with a quality of service guarantee. The book's focus on addressing network behavior ("real effects") in relation to the configuration of network elements (routers and switches), is both refreshing and insightful.

QOS-Enabled Networks contains up-to-date coverage of:

• QOS mechanisms in packet networks and how to apply them in practice
• QOS management features now common in modern-day routers
• How network behavior is related to configuration of network elements
• Layer 2 VPN and QOS
• QOS in mobile LTE networks

QOS-Enabled Networks is an invaluable guide for networking engineers needing to provide QOS services for service providers, ISPs and large enterprises, as well as for network design and operations engineers.

Peter Lundqvist is a senior Beta-engineer working in Juniper Networks Systest with support of field test of new features and solutions before they are public available. Prior to working in Juniper Networks Engineering department, Peter worked as professional services engineer with network design and implementation of large-scale networks including QOS topics. Peter has worked more than 8 years in Juniper Networks. Prior to joining Juniper Networks Peter worked in Cisco Systems as Consulting Engineer.

Foreword.

Preface.

Acknowledgements.

Abbreviations

PART I THE QOS REALM.

1 The QOS world.

1.1 Operation and Signaling.

1.2 Standards and Per-Hop Behavior.

1.3 Traffic Characterization.

1.4 A Router without QOS.

1.5 Conclusion.

References.

Further Reading.

2 The QOS Tools.

2.1 Classifiers and Classes of Service.

2.2 Metering and Coloring – CIR/PIR Model.

2.3 The Policer Tool.

2.4 The Shaper Function.

2.5 Comparing Policing and Shaping.

2.6 Queue.

2.7 The Scheduler.

2.8 The Rewrite Tool.

2.9 Example of Combining Tools.

2.10 Delay and Jitter Insertion.

2.11 Packet Loss.

2.12 Conclusion.

Reference. 

3 Challenges.

3.1 Defining the Classes of Service.

3.2 Classes of Service and Queues Mapping.

3.3 Inherent Delay Factors.

3.4 Congestion Points.

3.5 Trust Borders.

3.6 Granularity Levels.

3.7 Control Traffic.

3.8 Trust, Granularity, and Control Traffic.

3.9 Conclusion.

Further Reading. 

4 Traffic Types.

4.1 Anatomy of the TCP Protocol.

4.2 The TCP Session.

4.3 TCP Congestion Mechanism.

4.4 TCP Congestion Scenario.

4.5 PMTU.

4.6 QOS Conclusions for TCP.

4.7 Real-Time Traffic.

4.8 Anatomy of Real-Time Traffic.

4.9 RTP.

4.10 VOIP.

4.11 QOS Conclusions for VOIP.

4.12 IPTV.

4.13 Long-lived versus Short-lived Sessions.

4.14 Example of Internet Radio/Video.

4.15 Example of Peer-to-Peer (P2P) Applications.

4.16 Discovering P2P on the Network.

4.17 Illegal File Sharing and Copyright Violation.

4.18 QOS Conclusions for New Internet Applications.

References.

Further Reading.

PAER II TOOLS.

5 Classifiers.

5.1 Packet QOS Markings.

5.2 Inbound Interface Information.

5.3 Deep Packet inspection.

5.4 Selecting Classifiers.

5.5 The QOS Network Perspective.

5.6 MPLS DiffServ-TE.

5.7 Mixing Different QOS Realms.

5.8 Conclusions.

References.

6 Policing and Shaping.

6.1 Token Buckets.

6.2 Traffic Bursts.

6.3 Dual-Rate Token Buckets.

6.4 Shapers and Leaky Buckets.

6.5 Excess Traffic and Oversubscription.

6.6 Comparing and Applying Policer and Shaper Tools.

6.7 Conclusion.

Reference.

7 Queuing and Scheduling.

7.1 Queuing and Scheduling Concepts.

7.2 Packets and Cellification.

7.3 Different Types of Queuing Disciplines.

7.4 FIFO - First in, First out.

7.5 Fair Queuing.

7.6 Priority Queuing.

7.7 Weighted Fair Queueing.

7.8 Weighted Round Robin.

7.9 Deficit Weighted Round Robin.

7.10 Priority-Based Deficit Weighted Round Robin.

7.10 Conclusions about the Best Queuing Discipline.

Further Reading.

8 Advanced Queueing topics.

8.1 Hierarchical Scheduling.

8.2 Queues Lengths and Buffer Size.

8.3 Dynamically Sized versus Fixed-size Queue Buffers.

8.4 RED - Random Early Discard.

8.5 Using RED with TCP Sessions.

8.6 Differentiating Traffic Inside a Queue with WRED.

8.7 Head versus Tail RED.

8.8 Segmented and interpolated RED Profiles.

8.9 Conclusion.

Further Reading.

PART III CASE STUDIES.

9 The VPLS Case Study.

9.1 High-Level Case Study Overview.

9.2 Virtual Private Networks.

9.3 Service Overview.

9.4 Service Technical Implementation.

9.5 Network Internals.

9.6 Classes of Service and Queue Mapping.

9.7 Classification and Trust Borders.

9.8 Admission Control.

9.9 Rewrite Rules.

9.10 Absorbing Traffic Bursts at the Egress.

9.11 Queues and Scheduling at Core-Facing Interfaces.

9.12 Queues and Scheduling at Customer-Facing Interfaces.

9.13 Tracing a Packet Through the Network.

9.14 Adding More Services.

9.15 Multicast Traffic.

9.16 Using Bandwidth Reservations.

9.17 Conclusion.

Further Reading.

10 Case Study IP RAN and Mobile Backhaul QOS.

10.1 Evolution from 2G to 4G.

10.2 2G Network Components.

10.3 Traffic on 2G Networks.

10.4 3G Network Components.

10.5 Traffic on 3G Networks.

10.6 LTE Network Components.

10.7 LTE Traffic Types.

10.8 LTE Traffic Classes.

10.9 Conclusion.

References.

Further Reading.

11 Conclusion.

Index.