Fundamentals
Silvano Da Ros
Cisco Press
800 East 96th Street
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Contents
Introduction xx
Part I Overview of Content Networking 3
Chapter 1 Introducing Content Networking 5
Defining Content Networking 5
Understanding the Underlying Technologies 7 Purpose and Goals 10
Scalability and Availability 10 Scaling the Application 10
Increasing Application Availability 11 Bandwidth and Response Times 13 Customization and Prioritization 14 Security, Auditing, and Monitoring 15
Securing Content on the Network 15
Securing Client and Origin Server Content 17 Monitoring, Administration, and Reporting 18
Cisco Content Networking Solutions 20
Content Switching 20
Server Load Balancing (SLB) 21
Firewall Load Balancing (FWLB) and VPN Load Balancing 21 Global Server Load Balancing 22
Application and Content Networking System 22 Content Edge Delivery 23
Content Distribution and Routing 24 Content Network Partnership Program 25
Content Management 25 Content Distribution 26 Content Providers 26 E-Learning Applications 26 Content Filtering and Scanning 26
Summary 27 Review Questions 27 Recommended Reading 27
Part II Networking Fundamentals 29
Chapter 2 Exploring the Network Layers 31
Ethernet Physical and Data Link Layers 32
Physical Layer 32
Ethernet Mechanical Properties—The Media 32 Ethernet Electrical Properties—The Signaling 37 Data Link Layer 42
Internet Protocol 45
Internet Control Message Protocol 50 Layer 3 Connectivity Determination 50 Unavailable Port Errors 51
Announcement of New Default Routers 51
Internet Group Management Protocol and Protocol Independent Multicast 51
Transport Layer 52
Transmission Control Protocol 52 TCP Three-Way Handshake 54 TCP Sliding Window 57 TCP Slow Start 60 TCP Congestion Avoidance 61 TCP Fast Retransmit 62 TCP Fast Recovery 63 TCP Maximum Segment Size 64 TCP over Satellite 64
TCP Variable Summary 65 User Datagram Protocol 66
Putting It All Together with a Detailed Network Trace 67 Summary 69
Review Questions 69 Recommended Reading 70
Chapter 3 Introducing Switching, Routing, and Address Translation 73
Exploring Ethernet Frame Switching 73 Configuring Virtual LANs 76
Configuring VLAN Trunking 76
Exploring MAC Learning with Multiple VLANs 77 VLAN Trunking Protocol 79
Understanding IP Routing 81
Configuring Static Routing 82 Understanding Dynamic Routing 84
Packet Switching 87
Process Switching Path 88 Fast Switching Path 89 Cisco Express Forwarding 91
Transparent Bridging 94
Exploring Network Address Translation 95
Source Network Address Translation 95 Static Network Address Translation 96 Dynamic NAT 97
Port Address Translation (PAT) 98 Destination Translation 99
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Review Questions 101 Recommended Reading 101
Chapter 4 Exploring Security Technologies and Network Infrastructure Designs 103
Filtering Packets with Access Control Lists 103Application Layer Inspection 106
Designing Enterprise Campuses 108 Designing Enterprise Edge Networks 111
Designing Headquarters with Remote Office Networks 114 Employing Internet Content Delivery Networks 116 Summary 117
Review Questions 117 Recommended Reading 117
Part III Intelligent Network Services for Content Delivery 119
Chapter 5 IP Multicast Content Delivery 121
Introducing IP Multicast 121
Internet Group Management Protocol 124
Internet Group Management Protocol, Version 1 124 Internet Group Management Protocol, Version 2 126 Internet Group Management Protocol, Version 3 127
Internet Standard Multicast 129
Distribution Trees 129
Protocol Independent Multicast 130 PIM Dense Mode 132
PIM Sparse Mode 134 PIM Sparse-Dense Mode 138 Bidirectional PIM 139
Configuring Rendezvous Point and Multicast Group Selection 141 Auto-RP 142
Bootstrap Routers 144
Configuring Inter-Domain Multicast with Multicast Source Discovery Protocol 146 AnycastRP 148
Layer 2 Multicast Protocols 149
Cisco Group Management Protocol (CGMP) 149 IGMP Snooping 150
Router-Port Group Management Protocol 151
Source Specific Multicast (SSM) 151
Ensuring Multicast Delivery With Pragmatic General Multicast 153 Summary 156
Review Questions 156 Recommended Reading 157
Chapter 6 Ensuring Content Delivery with Quality of Service 159
Classification and Marking 160
Marking Packets at Layer 3 161
Marking a Packet's IP Precedence Value 161
Marking a Packet's IP Differentiated Services Code Field 162 IP QoS Group Value 165
Marking Frames, Cells, and Trunks at Layer 2 165 Network-Based Application Recognition 166
Congestion Management 171
Understanding Layer 3 Router Packet Queuing 171 Configuring Priority Queuing 172
Configuring Custom Queuing 173
Configuring Weighted Fair Queuing and IP RTP Priority Queuing 174 Configuring Class-Based WFQ with Low Latency 176
Understanding Layer 2 Switch Ethernet Frame QoS 178
Congestion Avoidance 180
Configuring Weighted Random Early Detection 180 Understanding Policing and Shaping 183
Configuring Generic Traffic Shaping 186 Configuring Class-Based Traffic Shaping 187 Configuring Committed Access Rate (CAR) 187 Configuring Class-Based Policing 188 Configuring Two-Rate Policing 189 QoS Policy Signaling 189
BGP QoS Policy Propagation 189 Resource Reservation Protocol (RSVP) 190
Summary 194 Review Questions 195 Recommended Reading 195
Part IV Applications for Serving Content, at the Network Edge 197
Chapter 7 Presenting and Transforming Content 199
Introducing Markup Languages 199
Hypertext Markup Language 203 Extensible Markup Language 205
Extensible Hypertext Markup Language 207
Wireless Application Protocol Markup Languages 208
Transforming and Formatting Content 210
Transforming XML to XHMTUHMTL 210 Using Cascading Style Sheets 213 Transforming XML to XSL-FO 216
Summary 220 Review Questions 220 Recommended Reading 221
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Chapter 8 Exploring the Application Layer 223
HTTP 224
HTTP 1.0 Versus HTTP 1.1 224 HTTP Transactions 225
HTTP Connection Persistence and Pipelining 227 Maintaining Client-Side State with HTTP Cookies 230 HTTP Authentication 231
HTTP Caching Controls 233 Implicit Cache Controls 233 Explicit Controls 235
Public Key Infrastructure 236
Secret Key Cryptography 236 Public-Key Cryptography 237
Identity Theft Prevention Using Certificates 240 Secure Sockets Layer 246
File Transfer Protocol 250 Summary 254
Review Questions 254 Recommended Reading 254
Chapter 9 Introducing Streaming Media 257
Streaming Files and Content Playback 257
Creating Streaming On-Demand Container Files 261
Describing Streaming On-Demand Content with Meta-Files 264
Streaming with Microsoft WMT, Real Networks, and Apple QuickTime 265 Streaming Motion Picture Experts Group 266
Delivering Streaming Media 267
Transferring Streaming Media with the Real-Time Transport Protocol 268 Real-time Data Control with Real Time Streaming Protocol 270
Fast-Forwarding and Rewinding a Stream with RTSP 275
Using Quality of Service and IP Multicast with Streaming Media 275
Summary 276 Review Questions 277 Recommended Reading 277
Part V Application Layer Services for Content, within the Network 279
Chapter 10 Exploring Server Load Balancing 281
Exploring Your Server Load-Balancing Devices 287
Content Services Switch 289 CSS Packet Flow 290 CSS Models 292
Content Switch Operational Modes 298
Bridge-Mode Content Switching 300 Router Mode Content Switching 307
Load-Distribution Algorithms 311
Round Robin 311 Least Connections 313 Configuring Server Load 315
Calculating Relative Load 315 Calculating Absolute Load 317 Hash Distribution 319
Layer 5-7 Load Balancing 320
Equal-Cost Multi-Path Router Load Balancing 326
Health Checking 327
Out-of-Band Health Checking 327 ln-Band Health Checking 330
Session Persistence 332
Hash Load Balancing 332 IP Address Stickiness 332 HTTP Cookies 334 URL Sticky Strings 338 SSL Sticky 338
SIP Caller ID and MSISDN Number Sticky 340 Permanent Session Information Storage 340
Content Switch High Availability 340
CSS High Availability 341 CSM High Availability 347
Summary 352 Review Questions 352 Recommended Reading 352
Chapter 11 Switching Secured Content 355
SSL Termination 355
Configuring Your CSS for SSL Termination 358
Creating and Importing Keys and Certificates on the CSS 358 Terminating SSL on the CSS 360
Configuring URL and Header Rewrite on the CSS 362 Configuring Your Content Services Module with SSL 363
Creating and Importing Keys and Certificates on the CSM 363 Terminating SSL on the CSM-S 366
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Firewall Load Balancing 371
CSS Firewall Load Balancing 371 CSM Firewall Load Balancing 3 74
Configuring Reverse Stickiness 378 Configuring Single-CSM FWLB 379
VPN Load Balancing on the CSM 382
Preventing Connection Table Flooding using SYN-Cookies 384 Summary 385
Review Questions 385 Recommended Reading 385
Chapter 12 Exploring Global Server Load Balancing 387
Domain Name Service Operation 387
Introducing DNS Resource Records 389 Iterative DNS 390
Recursive DNS 392
BGP-Anycast and DNS Round-Robin 394 Exploring Distributed Director Technologies 394
Director Response Protocol and Boomerang Protocol 398 HTTP Redirection 402
A Robust Distributed Director Configuration 404
Exploring CSS Global Server Load Balancing 405
CSS Multisite Load Distribution 405 CSS Proximity-Based Load Balancing 408
Multitiered Proximity 411
Configuring Content Routing Agents 411
Exploring CSM Global Server Load Balancing 411 GSLB Stickiness 415
Summary 419 Review Questions 419 Recommended Reading 419
Part VI The Application and Content Networking System: Content Caching, Streaming,
Routing, and Distribution 421
Chapter 13 Delivering Cached and Streaming Media 423
Redirecting Application Requests 423
Introducing Web Cache Control Protocol 423 < Redirecting Traffic at Layer 2 and Layer 3 with Web Cache Control Protocol 426
Input Redirection Vs. Output Redirection 427 WCCP Load Distribution Using Hash Buckets 428
Recovering from a CE Failure 429 Adding a New CE 430
WCCP Hot Spot Handling 431 WCCP CE Load Shedding 432
WCCP Load Distribution Using Mask Assignment 432 Layer 4-7 Content Switch Redirection 434
Content Switch Load Distribution 435
Adding and Removing CEs When Using CSS Redirection 436 Request Redirection Topologies 437
Proxy Caching 437 Transparent Caching 440 Reverse Transparent Caching 441 Ensuring Content Freshness 445 Preloading Content 445
Transparently Delivering Authenticated Content 446
Enabling Transparent Value-Added Services on Your CEs 447
Content Authentication and Authorization 448 SSL Caching and Tunneling 449
Internet Content Adaptation Protocol 450 URL Filtering 452
Adjusting TCP/IP Parameter Values 453
Delivering Streaming Media 454
Streaming Video-on-Demand 456
Splitting Live and Prerecorded Broadcasts 457 Streaming Windows Media Technology 459
Configuring Windows Media Video on Demand 459
Configuring the CE Internal WMS Server for Live and Scheduled Rebroadcast Presentations 460
Streaming Real Media 464
RealProxy Video-on-Demand Caching 467 RealProxy Pull-Splitting 467
Summary 469 Review Questions 470 Recommended Reading 470
Chapter 14 Distributing and Routing Managed Content 473
E-learning and Corporate Communications 473 Software and File Distribution 474
Introducing Content Distribution and Routing 475
Initializing and Registering Your ACNS Network Devices 477 Setting Up Your ACNS Network for Acquisition and
Pre-Positioning 479
Creating Location Trees 480 Configuring Content Channels 482
Acquiring Content to Pre-Position 485
Configuring Acquisition Using Manifest Files 486 Configuring Acquisition Using the CDM GUI 487
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Configuring Content Pre-Positioning 488
Multicast-Push Distribution Trees 488 Unicast-Pull Distribution Trees 489
Content Request Routing 491
Simplified Hybrid Routing 491
Dynamic Proxy Auto-Configuration 494
Configuring Streaming Media 497
Streaming Prepositioned Video On-Demand Content 498
Creating Scheduled Live and Rebroadcast Programs in ACNS 500
Summary 503 Review Questions 503 Recommended Reading 503
