End-to-End Qos Network Design: Quality of Service in LANs
WANs and VPNs
Author: Tim Szigeti
Format: Hardcover · Published: November 2004
Dimensions: 0 x 0 x 0 in
ISBN: 1587051761 · Published by Cisco Press
Table of Contents
Introduction.
I. INTRODUCTION TO QoS.
1. Introduction to QoS.
A Brief Historical Perspective.
QoS Evolution.
User Network Expectations.
End User.
Information Technologies Management.
Understanding QoS.
EndtoEnd QoS.
All Packets Are (Not) Equal.
The Challenges of Converged Networks.
QoS Models.
IntServ Overview.
DiffServ Overview.
Introduction to the QoS Toolset.
Simplifying QoS.
Modular QoS CommandLine Interface.
QoS Baseline.
Default Behavior.
CrossPlatform Feature Consistency.
Automatic QoS.
If I Have AutoQoS, Why Should I Be Reading This Book?
The Continuing Evolution of QoS.
Summary.
Further Reading.
General.
IntServ.
DiffServ.
AutoQoS.
2. QoS Design Overview.
QoS Requirements of VoIP.
Voice (Bearer Traffic).
CallSignaling Traffic.
QoS Requirements of Video.
InteractiveVideo.
StreamingVideo.
QoS Requirements of Data.
BestEffort Data.
Bulk Data.
Transactional Data/Interactive Data.
Locally Defined MissionCritical Data.
DLSw+ Considerations.
QoS Requirements of the Control Plane.
IP Routing.
NetworkManagement.
Scavenger Class.
DoS and Worm Mitigation Strategy Through Scavenger Class QoS.
Principles of QoS Design.
General QoS Design Principles.
Classification and Marking Principles.
Policing and Markdown Principles.
Queuing and Dropping Principles.
DoS and Worm Mitigation Principles.
Deployment Principles.
Summary.
Further Reading.
II. QoS TOOLSET.
3. Classification and Marking Tools.
Classification Tools.
Modular QoS CommandLine Interface Class Maps.
NetworkBased Application Recognition.
Marking Tools.
ClassBased Marking.
ClassBased Policing.
Committed Access Rate.
PolicyBased Routing.
Voice Gateway Packet Marking.
Layer 2 Marking Fields.
Layer 3 Marking Fields.
Translating Layer 2 and Layer 3 Packet Markings.
Summary.
Further Reading.
General.
DiffServ.
L2 Protocol Tunneling.
VPN.
NBAR.
MPLS.
IP–ATM/Frame Relay Bundles.
Level 2 to Level 3 PacketMarking Translation.
4. Policing and Shaping Tools.
Token Bucket Algorithms.
Policers.
Policers as Markers.
Committed Access Rate.
ClassBased Policing.
Shapers.
Shaping Algorithms.
Shaping on ATM and Frame Relay Networks.
Generic Traffic Shaping.
ClassBased Shaping.
Further Reading.
DiffServ Policing Standards.
Policing.
ATM PVC Traffic Parameters.
Frame Relay Traffic Shaping.
Traffic Shaping.
5. CongestionManagement Tools.
Understanding Scheduling and Queuing.
Legacy Layer 3 Queuing Mechanisms.
Priority Queuing.
Custom Queuing.
Weighted Fair Queuing.
IP RTP Priority Queuing.
Currently Recommended Layer 3 Queuing Mechanisms.
ClassBased Weighted Fair Queuing.
LowLatency Queuing.
Layer 2 Queuing Tools.
Frame Relay DualFIFO.
PVC Interface Priority Queuing.
Txring.
PAK_priority.
Summary.
Further Reading.
Layer 3 Queuing.
Layer 2 Queuing.
Txring.
PAK_priority.
6. CongestionAvoidance Tools.
Random Early Detection.
Weighted Random Early Detection.
DSCPBased Weighted Random Early Detection.
Explicit Congestion Notification.
Summary.
Further Reading.
DiffServ Standards Relating to WRED.
Cisco IOS WRED Documentation.
7. LinkSpecific Tools.
HeaderCompression Techniques.
Related Standards.
TCP Header Compression.
RTP Header Compression.
Compression Formats.
Layer 2 Encapsulation Protocol Support.
Summary of cRTP Formats and Protocol Encapsulations.
ClassBased Header Compression.
Advanced Topics on cRTP.
Link Fragmentation and Interleaving.
Fragment Sizes.
Multilink PPP LFI.
FrameRelay Fragmentation.
LFI for Frame Relay/ATM Service Interworking.
IPSec Prefragmentation.
Summary.
Further Reading.
General.
IETF Standards.
Frame Relay Forum Standards.
Header Compression.
Link Fragmentation and Interleaving.
8. Bandwidth Reservation.
RSVP Overview.
RSVP Service Types.
Admission Control.
RSVP and LLQ.
MPLS Traffic Engineering.
Scalability.
RSVPDiffServ Integration.
Endpoints and Proxies.
Summary.
Further Reading.
Standards.
Cisco IOS Documentation.
9. Call Admission Control (CAC).
CAC Overview.
CAC Defined.
CAC Tool Categories.
Local CAC Tools.
MeasurementBased CAC Tools.
ResourceBased CAC Tools.
CallManager Locations CAC.
Gatekeeper CAC.
RSVP.
Example of VoIP CAC Through RSVP.
Summary.
Further Reading.
General.
Cisco IOS Documentation.
10. Catalyst QoS Tools.
Generic Catalyst QoS Models.
Classification, Marking, and Mapping.
Policing and Markdown.
Queuing and Dropping.
Catalyst 2950.
Catalyst 2950 Classification, Marking, and Mapping.
Catalyst 2950 Policing and Markdown.
Catalyst 2950 Queuing.
Catalyst 3550.
Catalyst 3550 Classification, Marking, and Mapping.
Catalyst 3550 Policing and Markdown.
Catalyst 3550 Queuing and Dropping.
Catalyst 2970, 3650, and 3750.
Catalyst 2970/3560/3750 Classification, Marking, and Mapping.
Catalyst 2970/3560/3750 Policing and Markdown.
Catalyst 2970/3560/3750 Queuing and Dropping.
Catalyst 4500.
Catalyst 4500 Classification, Marking, and Mapping.
Catalyst 4500 Policing and Markdown.
Catalyst 4500 Queuing and Dropping.
Catalyst 6500.
Catalyst 6500 Classification, Marking, and Mapping.
Catalyst 6500 Policing and Markdown.
Catalyst 6500 Queuing and Dropping.
Summary.
Further Reading.
11. WLAN QoS Tools.
QoS for Wireless LANs Versus QoS on Wired LANs.
Upstream Versus Downstream QoS.
IEEE 802.11 DCF.
Interframe Spaces.
Random Backoffs/Contention Windows.
IEEE 802.11e EDCF.
QoS Basic Service Set Information Element.
IEEE 802.1D Classes of Service.
QoS Operation on Cisco APs.
Configuring QoS on Cisco APs.
Summary.
Further Reading.
III. LAN QoS DESIGN.
12. Campus QoS Design.
DoS/WormMitigation Strategies.
ScavengerClass QoS Operation.
CallSignaling TCP/UDP Ports in Use.
AccessEdge Trust Models.
Trusted Endpoint Models.
Untrusted Endpoint Models.
Conditionally Trusted Endpoint(s) Models.
Catalyst 2950 QoS Considerations and Design.
Catalyst 2950: Trusted Endpoint Model.
Catalyst 2950: Untrusted PC with SoftPhone Model.
Catalyst 2950: Untrusted Server Model.
Catalyst 2950: Conditionally Trusted IP Phone + PC: Basic Model.
Catalyst 2950: Conditionally Trusted IP Phone + PC: Advanced Model.
Catalyst 2950: Queuing.
Catalyst 3550 QoS Considerations and Design.
Catalyst 3550: Trusted Endpoint Model.
Catalyst 3550: Untrusted PC with SoftPhone Model.
Catalyst 3550: Untrusted Server Model.
Catalyst 3550: Conditionally Trusted IP Phone + PC: Basic Model.
Catalyst 3550: Conditionally Trusted IP Phone + PC: Advanced Model.
Catalyst 3550: Queuing and Dropping.
Catalyst 2970/3560/3750 QoS Considerations and Design.
Catalyst 2970/3560/3750: Trusted Endpoint Model.
Catalyst 2970/3560/3750: Untrusted PC with SoftPhone Model.
Catalyst 2970/3560/3750: Untrusted Server Model.
Catalyst 2970/3560/3750: Conditionally Trusted IP Phone + PC: Basic Model.
Catalyst 2970/3560/3750: Conditionally Trusted IP Phone + PC: Advanced Model.
Catalyst 2970/3560/3750: Queuing and Dropping.
Catalyst 4500SupII+/III/IV/V QoS Considerations and Design.
Catalyst 4500: Trusted Endpoint Model.
Catalyst 4500: Untrusted PC with SoftPhone Model.
Catalyst 4500: Untrusted Server Model.
Catalyst 4500: Conditionally Trusted IP Phone + PC: Basic Model.
Catalyst 4500: Conditionally Trusted IP Phone + PC: Advanced Model.
Catalyst 4500: Queuing.
Catalyst 6500 QoS Considerations and Design.
Catalyst 6500: CatOS Defaults and Recommendations.
Catalyst 6500: Trusted Endpoint Model.
Catalyst 6500: Untrusted PC with SoftPhone Model.
Catalyst 6500: Untrusted Server Model.
Catalyst 6500: Conditionally Trusted IP Phone + PC: Basic Model.
Catalyst 6500: Conditionally Trusted IP Phone + PC: Advanced Model.
Catalyst 6500: Queuing and Dropping.
Catalyst 6500: PFC3 DistributionLayer (Cisco IOS) PerUser Microflow Policing.
WAN Aggregator/Branch Router Handoff Considerations.
Case Study: Campus QoS Design.
Summary.
Further Reading.
IV. WAN QoS DESIGN.
13. WAN Aggregator QoS Design.
Where Is QoS Needed over the WAN?
WAN Edge QoS Design Considerations.
Software QoS.
Bandwidth Provisioning for BestEffort Traffic.
Bandwidth Provisioning for RealTime Traffic.
Serialization.
IP RTP Header Compression.
Txring Tuning.
PAK_priority.
Link Speeds.
Distributed Platform QoS and Consistent QoS Behavior.
WAN Edge Classification and Provisioning Models.
Slow/Medium LinkSpeed QoS Class Models.
High Link Speed QoS Class Models.
WAN Edge LinkSpecific QoS Design.
Leased Lines.
Frame Relay.
ATM.
ATMtoFrame Relay Service Interworking.
ISDN.
Case Study: WAN Aggregation Router QoS Design.
Summary.
Further Reading.
14. Branch Router QoS Design.
Branch WAN Edge QoS Design.
Unidirectional Applications.
Branch Router LAN Edge QoS Design.
DSCPtoCoS Remapping.
BranchtoCampus Classification and Marking.
NBAR KnownWorm Classification and Policing.
Case Study: Branch Router QoS Design.
Summary.
Further Reading.
V. VPN QoS DESIGN.
15. MPLS VPN QoS Design.
Where Is QoS Needed over an MPLS VPN?
Customer Edge QoS Design Considerations.
Layer 2 Access (LinkSpecific) QoS Design.
ServiceProvider ServiceLevel Agreements.
EnterprisetoService Provider Mapping Models.
ProviderEdge QoS Considerations.
Service ProvidertoEnterprise Models.
MPLS DiffServ Tunneling Modes.
Core QoS Considerations.
Aggregate Bandwidth Overprovisioning.
DiffServ in the Backbone.
MPLS Traffic Engineering.
Case Study: MPLS VPN QoS Design (CE/PE/P Routers).
Summary.
Further Reading.
16. IPSec VPN QoS Design.
SitetoSite V3PN QoS Considerations.
IPSec VPN Modes of Operation.
Packet Overhead Increases.
cRTP and IPSec Incompatibility.
Prefragmentation.
Bandwidth Provisioning.
Logical Topologies.
Delay Budget Increases.
ToS Byte Preservation.
QoS PreClassify.
PreEncryption Queuing.
AntiReplay Implications.
Control Plane Provisioning.
SitetoSite V3PN QoS Designs.
Headend VPN Edge QoS Options for SitetoSite V3PNs.
Teleworker V3PN QoS Considerations.
Teleworker Deployment Models.
BroadbandAccess Technologies.
Bandwidth Provisioning.
Asymmetric Links and Unidirectional QoS.
Broadband Serialization Mitigation Through TCP Maximum Segment Size Tuning.
Split Tunneling.
Teleworker V3PN QoS Designs.
Case Study: IPSec VPN QoS Design.
Summary.
Further Reading.
Appendix. QoS “AtAGlance” Summaries.
Index.