Contents The Technical Reference Guide contains the following major sections: • iDirect System Overview • DVB-S2 in iDirect Networks • Modulation Modes and FEC Rates • iDirect Spread Spe
Trang 1Technical Reference Guide
iDirect Satellite Routers
iDX Release 3.5.x
February 22, 2017
Technical Reference Guide for iDX Release 3.5.x
Trang 2Copyright © 2017 VT iDirect, Inc., 13861 Sunrise Valley Drive, Suite 300, Herndon, VA 20171, USA.
All rights reserved Reproduction in whole or in part without permission is prohibited Information contained herein
is subject to change without notice The specifications and information regarding the products in this document are subject to change without notice All statements, information and recommendations in this document are believed
to be accurate, but are presented without warranty of any kind, express, or implied Users must take full
responsibility for their application of any products Trademarks, brand names and products mentioned in this document are the property of their respective owners All such references are used strictly in an editorial fashion with no intent to convey any affiliation with the name or the product's rightful owner.
VT iDirect ® is a global leader in IP-based satellite communications providing technology and solutions that enable our partners worldwide to optimize their networks, differentiate their services and profitably expand their
businesses Our product portfolio, branded under the name iDirect ®, sets standards in performance and efficiency
to deliver voice, video and data connectivity anywhere in the world VT iDirect ® is the world’s largest TDMA enterprise VSAT manufacturer and is the leader in key industries including mobility, military/government and cellular backhaul.
Company Web site: www.idirect.net ~ Main Phone: 703.648.8000
TAC Contact Information: Phone: 703.648.8151 ~ Email: tac@idirect.net ~ Web site: tac.idirect.net
iDirect Government™, created in 2007, is a wholly owned subsidiary of iDirect and was formed to better serve the
U.S government and defense communities
Company Web site: www.idirectgov.com ~ Main Phone: 703.648.8118
TAC Contact Information: Phone: 703.648.8111 ~ Email: tac@idirectgov.com ~ Web site: tac.idirectgov.com
Document Name: REF_TRG_T0000772_ iDX 3.5.x_RevC_02222017.pdf
Document Part Number: T0000772
Trang 3Revision History
Revision History
The following table shows all revisions for this document To determine if this is the latest revision, check the TAC Web site at http://tac.idirect.net
A 09/27/2016 Initial release of Evolution Release iDX 3.5.1.
B 01/04/2017 Added a Multichannel Line Card restriction and updated the Max
Composite Information Bit Rate (Mbps) under the Multichannel Receive Line Card Parameters table in chapter Multichannel Line Cards on page 27.
C 02/22/2017 • Added information on iVantage API See iVantage API on page 273.
• Added a note about carrier’s C/No See Adaptive TDMA on
page 35
Trang 4Revision History
Trang 5Contents
List of Figures .xviii
About .xxiii
Purpose xxiii
Audience xxiii
Contents xxiii
Document Conventions xxiv
Getting Help xxv
Document Set xxvi
Chapter 1 iDirect System Overview 1
System Overview 1
IP Network Architecture 3
Chapter 2 DVB-S2 in iDirect Networks 7
DVB-S2 Key Concepts 7
DVB-S2 in iDirect 9
32APSK Support in DVB-S2 Downstream 9
Remote LNB Consideration 10
Mobility and Fade Considerations 10
Transponder Consideration 10
Linear Distortion 10
DVB-S2 Downstream 11
ACM Operation 12
Quality of Service in DVB-S2 ACM Networks 14
Trang 6Remote Nominal MODCOD 14
Remote Maximum MODCOD 14
Fixed Bandwidth Operation 14
Enhanced Information Rate 15
Scaling Factors for Fixed Bandwidth Allocation 15
Bandwidth Allocation Fairness 17
DVB-S2 Configuration 17
DVB-S2 Performance Monitoring 18
Chapter 3 Modulation Modes and FEC Rates 19
iDirect Modulation Modes And FEC Rates 19
DVB-S2 Modulation Modes and FEC Rates 19
2D 16-State Inbound Coding for DVB-S2 Networks 19
TDMA Waveform Enhancements 20
Chapter 4 iDirect Spread Spectrum Networks 23
Overview of Spread Spectrum 23
Spread Spectrum Hardware Components 24
Spread TDMA Upstream Specifications 25
Spread SCPC Upstream Specifications 25
Chapter 5 Multichannel Line Cards 27
Multichannel Line Card Model Types 27
Multichannel Line Card Receive Modes 27
Multichannel Line Card Restrictions and Limits 28
Chapter 6 SCPC Return Channels 31
Hardware Support and License Requirements 31
Single Channel vs Multichannel SCPC Return 32
SCPC Return Feature on Remotes 32
VNO for SCPC Return 33
Trang 7Chapter 7 Adaptive TDMA 35
Theory of Operation 35
Short Term Adaptivity and Real-Time Resource Management 36
Medium Term Adaptivity 37
Long Term Adaptivity 38
C/N0 and C/N 38
Fade Margin and Measurement Interval Calculations 40
C/N Dynamic Range for Individual Carriers 42
C/N0 Dynamic Range for Inroute Group 42
Power Control 43
Considerations of TDMA Frame-Filling Efficiency 43
Frame Filling 44
Adaptive TDMA Configuration and Constraints 44
Remote Configuration 46
Reference Carrier Parameters 46
Remote Carrier Constraint Parameters 47
47
Chapter 8 Multicast Fast Path 49
Overview 49
Multicast Fast Path Streams 49
Multicast Fast Path Encryption 50
Multicast Fast Path Encryption Key Management 51
Enabling Multicast Fast Path Encryption 52
Multicast Fast Path Encryption Monitoring 52
X7 Multicast Fast Path on a Second Downstream Carrier 53
Enabling X7 Multicast Fast Path from a Second Downstream 53
Setting Up Multicast Fast Path Encryption Using a GKD Server 55
Configuring GKD for Encrypted Multicast Fast Path in Secondary Networks 55
Protocol Processor Configuration 56
Network Configuration 57
X7 Remote Configuration 58
Trang 8Creating a GKD Options File for MCFPE for X7 Remotes with a Second Downstream Carrier 59
Supported List of Configurations 61
Chapter 9 QoS Implementation Principles 65
Quality of Service (QoS) 65
QoS Measures 65
iDirect QoS Profiles 66
Classification and Scheduling of Packets 68
Service Levels 68
Packet Scheduling 69
Priority Queues 70
Class-Based Weighted Fair Queues 70
Best Effort Queues 70
Application Throughput 71
Minimum Information Rate 71
Committed Information Rate (CIR) 72
Maximum Information Rate 72
Free Slot Allocation 73
Compressed Real-Time Protocol 73
Sticky CIR 73
Application Jitter 73
TDMA Slot Feathering 74
Packet Segmentation 74
Application Latency 74
Maximum Channel Efficiency vs Minimum Latency 75
Group QoS 75
Group QoS Structure 76
Bandwidth Pool 76
Bandwidth Group 76
Service Group 77
Application 77
Service Profiles 78
Trang 9Remote Profiles 78
Group QoS Scenarios 79
Physical Segregation Scenario 79
CIR Per Application Scenario 80
Tiered Service Scenario 81
Third Level of Segregation by VLAN Scenario 82
The Shared Remote Scenario 83
Remote Service Group Scenario 85
DVB-S2 ACM Scenario 1: Scaled Aggregate CIRs Below Partition’s CIR 87
DVB-S2 ACM Scenario 2: Scaled Aggregate CIRs Exceeds Partition’s CIR 89
Bandwidth Allocation Fairness Relative to CIR 90
Bandwidth Allocation Fairness Relative to MODCOD 91
Chapter 10 TDMA Initial Transmit Power 93
All Remotes Need To Transmit Bursts in the Same C/N Range 94
What Happens When Initial Tx Power Is Set Incorrectly? 94
When Initial Transmit Power is Too High 94
When Initial Transmit Power is Too Low 95
Chapter 11 Uplink Control Process 97
TDMA Uplink Control 97
Acquisition 97
Network Operation 99
UCP Correction Processing 99
UCP Symbol Timing 99
UCP Frequency Tracking 100
UCP Power Control and Fade Detection 100
SCPC Return Uplink Control 103
UCP Power Adjustment for SCPC Upstream Carriers 104
Viewing UCP Statistics in iMonitor 104
Chapter 12 Remote Idle and Dormant States 107
Overview 107
Trang 10Feature Description 108
Chapter 13 Verifying Error Thresholds Using IP Packets 113
Introduction 113
TDMA Upstream Threshold Testing 113
Upstream Example 1 114
Upstream Example 2 114
DVB-S2 Downstream Threshold Testing 115
Downstream Example 115
Chapter 14 Global NMS Architecture 117
How the Global NMS Works 117
Sample Global NMS Network 118
Chapter 15 Security Best Practices 119
Hub and NMS Server Security 119
Network Isolation and External Access 119
Server Password Security 119
Secure Server Connections 120
Encryption of Backup Files Before Archiving 120
Clearing Data from Decommissioned Servers 120
NMS Client Security 120
User Passwords and Permissions 120
Client Access 121
Remote Access 121
Console Password Security 121
Clearing Data from Decommissioned Remotes and Line Cards 121
DNS Queries on Satellite (SAT0) Interface of Remote 122
Chapter 16 Global Protocol Processor Architecture 123
Remote Distribution 123
De-coupling of NMS and Data Path Components 123
Trang 11Chapter 17 Distributed NMS Server 125
Distributed NMS Server Architecture 125
iBuilder and iMonitor 126
Chapter 18 Transmission Security (TRANSEC) 127
What is TRANSEC? 127
iDirect TRANSEC 128
TRANSEC Key types 128
TRANSEC Module 129
One-way TRANSEC 129
DVB-S2 Downstream TRANSEC 129
Upstream TRANSEC 131
Disguising Remote 131
Generating the TDMA Initialization Vector 133
Upstream TRANSEC Segment 134
ACQ Burst Obfuscation 134
TRANSEC Dynamic Key Management 136
TRANSEC Remote Admission Protocol 139
ACC Key Management 139
ACC Key Roll 140
Manual ACC Key Update 140
Automatic Beam Selection (ABS) and TRANSEC 140
Chapter 19 Remote Sleep Mode 143
Feature Description 143
Awakening Methods 144
Operator-Commanded Awakening 144
Activity Related Awakening 144
Enabling Remote Sleep Mode 144
Power Consumption 145
Chapter 20 Remote Acquisition 147
Acquisition Process 147
Trang 12Acquisition Algorithm 149
Superburst Acquisition 150
Advantages of Superburst 150
Considerations When Using Superburst 151
Acquisition Carrier Selection 151
Transmit Power Adjustment for Non-reference Carriers 151
Ability to Acquire When No Traffic Carrier Is Available 151
Chapter 21 Automatic Beam Selection 153
Automatic Beam Selection Overview 153
Theory of Operation 154
Overview 154
iDirect Beam Map File and Map Server 154
Beam Selection 155
Conveyance Beam Map File 156
Regulatory Considerations 156
Beam Characteristics: Visibility and Usability 157
Selecting a Beam without a Map 158
Controlling the Antenna 159
IP Mobility 159
Initial Transmit Power 159
Calculation of Initial Transmit Power 160
Setting the Initial Transmit Power Offset 160
Determining the Initial Transmit Power Offset for Other Beams 161
Receive-Only Mode for ABS Remotes 163
Multiple Map Servers per Network 163
Operational Scenarios 164
Creating the Network 164
Adding a Remote 164
Normal Operations 165
Mapless Operations 166
Blockages and Beam Outages 166
Trang 13Error Recovery 166
Chapter 22 Hub Geographic Redundancy 167
Feature Description 167
Configuring Wait Time Interval for an Out-of-Network Remote 167
Chapter 23 Carrier Occupied Bandwidth 169
Overview 169
Considerations When Determining Guard Band 170
DVB-S2 Roll-Off Factors 171
Group Delay and Downstream Performance 172
Improving Throughput by Reducing Guard Band 173
DVB-S2 Guard Band Constraints 173
Adjacent Channel Interference 174
Chapter 24 Alternate Downstream Carrier 177
Background 177
Feature Description 177
Chapter 25 Transmit Key Line 179
Introduction 179
Feature Description 179
Chapter 26 NMS Database Replication 181
Benefits of NMS Database Replication 181
Feature Description 182
NMS Database Replication Architecture 182
Replicating iDirect NMS Databases 183
NMS Database Replication on a Distributed NMS 185
Setting Up NMS Database Replication 187
Examples 188
Enable Replication to a Single Backup Server 188
Add Two Additional Backup NMS Servers as MySQL Slaves 189
Trang 14Enable Replication to a Redundant NMS Server 189
Stop Replication to a Backup NMS Server 190
Monitoring NMS Database Replication 190
Events And Warnings 191
Viewing Replication Conditions in iMonitor 191
Recovering from Replication Failures 192
Chapter 27 Feature and Chassis Licensing 195
iDirect Licensing Requirements 195
Chapter 28 Hub Line Card Failover 197
Basic Failover Concepts 197
Warm Standby versus Cold Standby Line Card Failover 197
Failover Sequence of Events 198
Chapter 29 NMS, PP and GKD Server Port Assignments 201
NMS Server Ports 201
PP Controller Ports 202
GKD Server Ports 203
Protocol Processor Ports 203
Port Assignments for NMS/Upstream Router Traffic Flow 204
Chapter 30 VRRP and Remote LAN Port Monitoring 205
Virtual Router Redundancy Protocol (VRRP) 205
VRRP Overview 205
Configuring VRRP on iDirect Remotes 208
VRRP Route Tracking 211
Remote LAN Port Monitoring 214
Monitoring VRRP Status and Remote LAN Status 215
Remote Console Commands 216
Chapter 31 Layer 2 over Satellite 219
L2oS Overview 219
Trang 15L2oS Benefits 220
L2oS Reference Model 221
Satellite Virtual Network and Service Delimiting Tags 222
TCP Acceleration 224
SVNs Scalability 224
L2oS Service Modes 225
Virtual Private LAN Service 225
Virtual Private Wire Service 226
Virtual Private Wire Service-Evolved Packet Core 226
Layer 2/Layer 3 Hybrid Mode 226
Advanced Header Compression 227
MAC Address Learning 229
MAC Addresses Scalability 230
Deleting MAC Addresses from the Forward Information Base Table 230
Forwarding Rules 231
Bidirectional Forwarding Detection 232
L2oS Configuration 233
Layer 2/Layer 3 Hybrid Mode Configuration 233
L2oS Hub Parameters 234
Remote L2oS SDT and SVN Parameters 236
Configuring Advanced Header Compression 238
Assigning VLAN IDs to X7 LAN Ports 239
Configuring Rules for Classifying Layer 2 Traffic 242
Monitoring L2oS Networks 243
Changing MTU at Protocol Processor in L2oS Network 244
L2oS Examples including Layer 2 and Layer 3 Hybrid Mode 245
Layer 2/Layer 3 Hybrid Mode with VLAN Tagging at Hub 253
Layer 2/ Layer 3 Hybrid Mode in QinQ Tagging at Hub 254
Chapter 32 Acquisition Invitation Improvements 257
Introduction 257
Supported Remotes 257
Trang 16Inter- and Intra-PP Stack Messaging Framework 257
Intra-PP Stack Messaging 258
Message Forwarding to Other Protocol Processor Stacks 258
Out-of-Network Remote Queues 259
Normal Priority Queue 259
Beam Switch Priority Queue 259
Recently Dropped Priority Queue 259
Acquisition Invitation Improvement Features 259
Remote Signaled Fast Beam Switching 260
Stop Sweeping Remote In-Network Feature 260
RecentDrop from Local Network Sweep Feature 261
RecentDrop from Network Elsewhere Feature 261
Remote Signaled Beam Switch API Usage 262
API Features 262
Beam Switching 262
Receive-Only Mode 262
Timeout 263
Beam List 263
Status 263
Initial Transmit Power 263
OpenAMIP 264
Using the API 264
Primary Receiver Operation 264
Second Receiver Operation 265
Chapter 33 Multiprotocol Encapsulation 267
Overview 267
System Architecture 268
Hardware Requirements 268
Software Requirements 268
Routing and Configuration 269
Trang 17Appendix A Stacking 271
Appendix B iVantage API 273
API Limitations 274
API Processes 274
Configuring the API Services 274
Examples 275
Trang 18List of Figures
List of Figures
Figure 1-1 Sample iDirect Network 2
Figure 1-2 iDirect IP Architecture – Multiple VLANs per Remote 3
Figure 1-3 iDirect IP Architecture – VLAN Spanning Remotes 4
Figure 1-4 iDirect IP Architecture – Classic IP Configuration 5
Figure 2-1 Bandwidth Scale Factor normalized to max MODCOD 32APSK-8/9 9
Figure 2-2 Physical Layer Frames 11
Figure 2-3 Feedback Loop from Remote to Protocol Processor 13
Figure 2-4 Feedback Loop with Back-Off from Line Card to Protocol Processor 13
Figure 3-1 TDMA Burst Format with Distributed Pilots 21
Figure 4-1 Spread Spectrum Network Diagram 23
Figure 7-1 Control Elements of iDirect’s ATDMA System 36
Figure 7-2 Fade Slope Distribution at Various Fade Levels (ITU-R Rec P.1623-1) 40
Figure 8-1 Enabling Multicast Fast Path Encryption 52
Figure 8-2 Protocol Processor GKD Tab 57
Figure 8-3 Network Information Tab 58
Figure 8-4 Protocol Processor Options File with GKD Node Definitions 59
Figure 9-1 Group QoS Structure 76
Figure 9-2 Physical Segregation Scenario 79
Figure 9-3 CIR Per Application Scenario 80
Figure 9-4 Tiered Service Scenario 81
Figure 9-5 Third Level VLAN Scenario 83
Figure 9-6 Shared Remote Scenario 84
Figure 9-7 Remote Service Group Scenario 86
Figure 9-8 Scaled Aggregate CIRs Below Partition’s CIR 88
Figure 9-9 Scaled Aggregate CIRs Exceed Partition’s CIR 89
Figure 9-10 Bandwidth Allocation Fairness Relative to CIR 90
Figure 9-11 Bandwidth Allocation Fairness Relative to Nominal MODCOD 91
Figure 10-1 Optimal C/N Detection Range 94
Figure 10-2 Skewed C/N Detection Range: Initial Transmit Power Too High 95
Figure 10-3 Skewed Detection Range: Initial Transmit Power Too Low 95
Figure 11-1 TDMA Frame Format 97
Figure 11-2 iBuilder: Maximum Speed and Guard Interval for Inroute Group 100
Figure 11-3 Uplink Power Control During Remote Fade 102
Figure 11-4 iMonitor UCP Statistics 104
Figure 11-5 Remote Upstream Acquisition Statistics 106
Figure 12-1 Active, Idle and Dormant State Change Diagram 108
Figure 12-2 Configuring Active, Idle and Dormant States 108
Figure 12-3 Upstream Service Level with Trigger State Change Selected 110
Trang 19List of Figures
Figure 14-1 Global NMS Database Relationships 117
Figure 14-2 Sample Global NMS Network Diagram 118
Figure 16-1 Protocol Processor Architecture 124
Figure 17-1 Sample Distributed NMS Configuration 125
Figure 18-1 DVB-S2 TRANSEC Frame Structure 130
Figure 18-2 Disguising Which Key is Used for a Burst 132
Figure 18-3 Code Field 132
Figure 18-4 Generating the Upstream Initialization Vector 133
Figure 18-5 Upstream ACQ Burst Obfuscation 135
Figure 18-6 Key Distribution Protocol 136
Figure 18-7 Key Roll Data Structure 137
Figure 18-8 Host Keying Protocol 138
Figure 21-1 iMonitor Probe: Remote Power Section 161
Figure 21-2 Remote VSAT Tab: Entering the Initial Transmit Power Offset 161
Figure 21-3 Absolute vs Generated G/T Contours for Two Beams 162
Figure 23-1 Spectral Mask Illustrating 20% and 5% Roll-Off Factors 171
Figure 23-2 Adjacent Carrier Interference Example 174
Figure 26-1 NMS Database Replication Architecture 182
Figure 26-2 NMS Database Replication from a Single Primary NMS Server 184
Figure 26-3 NMS Database Replication on a Distributed NMS 186
Figure 26-4 Enabling NMS Database Replication to a Backup Server 189
Figure 26-5 Replication Conditions Viewed in iMonitor 192
Figure 26-6 Replication Error Resulting in Active Condition in iMonitor 192
Figure 28-1 Line Card Failover Sequence of Events 199
Figure 30-1 Example of a Virtual Router 207
Figure 30-2 Example VRRP Configuration in iBuilder 210
Figure 30-3 Changing the Frequency of Router Priority Messages 213
Figure 30-4 Changing a Remote’s Router Priority Message Timeout 213
Figure 30-5 Example of LAN Port Monitoring Configuration for Multiple Ports in iBuilder 215
Figure 30-6 Example LAN Port Monitoring Configuration for Single Port in iBuilder 215
Figure 30-7 VRRP and Remote LAN Status Events in iMonitor 216
Figure 31-1 Transparent Layer 2 Emulation 220
Figure 31-2 L2oS Reference Model 221
Figure 31-3 L2oS Reference Model Applied to iDirect 222
Figure 31-4 SDT Mode = VLAN 223
Figure 31-5 SDT Mode = QinQ (Double Tagged) 223
Figure 31-6 SDT Mode = Access (Remote Side Only) 224
Figure 31-7 L2oS Forwarding Rules 231
Figure 31-8 Enabling L2oS 234
Figure 31-9 iBuilder Protocol Processor L2oS Tab 235
Trang 20List of Figures
Figure 31-10 iBuilder Remote L2oS Tab 236
Figure 31-11 L2oS Advanced Header Compression 238
Figure 31-12 X7 Switch Configuration 240
Figure 31-13 Assigning a Layer 2 VLAN ID to an X7 Port 241
Figure 31-14 Classifiers for Layer 2 Traffic 242
Figure 31-15 Configuring IPv6 Packet Classifier in iBuilder 243
Figure 31-16 VPWS Service with Remote Single End Points 245
Figure 31-17 VPWS Service with IPv6 Traffic 246
Figure 31-18 VPWS Service with Multiple Remote VLANs 247
Figure 31-19 VPWS Service with Multiple VLANs 248
Figure 31-20 VPLS Service with Remote-to-Remote Routing 249
Figure 31-21 VPWS Service with Remote-to-Remote Routing by Upstream Router 250
Figure 31-22 Hub-Side QinQ and Remote VLAN 251
Figure 31-23 BGP Peering 252
Figure 31-24 MPLS with VRF Lite Over the Air 253
Figure 31-25 Layer 2/Layer 3 Hybrid Mode with VLAN Tagging at Hub 253
Figure 31-26 Layer 2/Layer 3 Hybrid Mode with QinQ Tagging at Hub 254
Figure 33-1 System Architecture 268
Figure B-1 NMS-Server Architecture 273
Trang 21List of Tables
List of Tables
Table 2-1 DVB-S2 Short Frame MODCODs 8
Table 2-2 ACM MODCOD Scaling Factors 15
Table 4-1 Spread Spectrum: TDMA Upstream Specifications 25
Table 4-2 Spread Spectrum: SCPC Upstream Specifications 25
Table 5-1 Multichannel Receive Line Card Parameters (XLC-M and eM0DM) 29
Table 5-2 Multichannel Receive Line Card Parameters (ULC-R and DLC-R) 30
Table 6-1 Single Channel vs Multichannel SCPC 32
Table 7-1 Fade Slope Values Used For Calculations 41
Table 7-2 Example of M1 Margin and Measurement Spacing Settings 41
Table 7-3 Sample Adaptive Inroute Group Configuration 45
Table 8-1 Supported MCFPE Configurations 61
Table 19-1 Power Consumption: Normal Operations vs Remote Sleep Mode 145
Table 23-1 Increasing Information Rate by Reducing Guard Band 173
Table 23-2 DVB-S2 Guard Band Constraints 173
Table 29-1 NMS Server Ports 201
Table 29-2 pp_controller Ports 202
Table 29-3 GKD Server Ports 203
Table 29-4 samnc Ports 203
Table 29-5 Protocol Processor Port Ranges 203
Table 29-6 Port Designations for NMS/Upstream Router Traffic 204
Table 30-1 PP Routing Table Operations: LAN Port Monitoring and VRRP 214
Table 31-1 SDT Support Matrix 224
Table 31-2 Maximum Number of Layer 3 SVNs Per Network (Relative to Network Size) 225
Table 31-3 IPv4 Header Compression 228
Table 31-4 IPv4 Header Compression with IP Extensions 228
Table 31-5 IPv6 Header Compression 229
Table 31-6 IPv6 Header Compression with IP Extensions 229
Table 31-7 BFD Options Trade-offs 233
Table 31-8 Header Compression Examples 239
Table B-1 API Processes 274
Trang 22List of Tables
Trang 23About
Purpose
The Technical Reference Guide provides detailed technical information on iDirect technology
and major features as implemented in iDX Release 3.5.x
Audience
The Technical Reference Guide is intended for iDirect Network Operators, network architects,
and anyone upgrading to iDX Release 3.5.x
Contents
The Technical Reference Guide contains the following major sections:
• iDirect System Overview
• DVB-S2 in iDirect Networks
• Modulation Modes and FEC Rates
• iDirect Spread Spectrum Networks
• Multichannel Line Cards
• SCPC Return Channels
• Adaptive TDMA
• Multicast Fast Path
• QoS Implementation Principles
• TDMA Initial Transmit Power
• Uplink Control Process
• Remote Idle and Dormant States
• Verifying Error Thresholds Using IP Packets
• Global NMS Architecture
• Security Best Practices
• Global Protocol Processor Architecture
Trang 24• Distributed NMS Server
• Transmission Security (TRANSEC)
• Remote Sleep Mode
• Remote Acquisition
• Automatic Beam Selection
• Hub Geographic Redundancy
• Carrier Occupied Bandwidth
• Alternate Downstream Carrier
• Transmit Key Line
• NMS Database Replication
• Feature and Chassis Licensing
• Hub Line Card Failover
• NMS, PP and GKD Server Port Assignments
• VRRP and Remote LAN Port Monitoring
• Layer 2 over Satellite
• Acquisition Invitation Improvements
Document Conventions
This section illustrates and describes the conventions used throughout this document
Command Used when the user is required to
enter a command at a command line prompt or in a console.
Enter the command:
Used when specifying names of commands, menus, folders, tabs, dialogs, list boxes, and options.
1 To add a remote to an inroute group, right-click
the Inroute Group and select Add Remote.
The Remote dialog box has a number of selectable tabs across the top The Information
user-tab is visible when the dialog box opens.
Hyperlink Used to show all hyperlinked text
within a document or external links such as web page URLs.
For instructions on adding a line card to the network tree, seeAdding a Line Card on page 108.
Trang 25Getting Help
The iDirect Technical Assistance Center (TAC) and the iDirect Government Technical
Assistance Center (TAC) are available to provide assistance 24 hours a day, 365 days a year Software user guides, installation procedures, FAQs, and other documents that support iDirect and iDirect Government products are available on the respective TAC Web site:
• Access the iDirect TAC Web site at http://tac.idirect.net
• Access the iDirect Government TAC Web site at http://tac.idirectgov.com
The iDirect TAC may be contacted by telephone or email:
• iDirect: techpubs@idirect.net
• iDirect Government: techpubs@idirectgov.com
For sales or product purchasing information contact iDirect Corporate Sales at the following telephone number or e-mail address:
• Telephone: 703.648.8000
• E-mail: sales@idirect.net
NOTE: A Note is a statement or other notification that adds, emphasizes, or
clarifies essential information of special importance or interest
CAUTION: A Caution highlights an essential operating or maintenance procedure,
practice, condition, or statement which, if not strictly observed, could result in damage to, or destruction of, equipment or a condition that adversely affects system operation
WARNING: A Warning highlights an essential operating or maintenance
procedure, practice, condition or statement which, if not strictly observed, could result in injury or death or long term health hazards
Trang 26Document Set
The following iDirect documents are available at http://tac.idirect.net and contain
information relevant to installing and using iDirect satellite network software and equipment
• Release Notes
• Software Installation Guide or Network Upgrade Procedure Guide
• iBuilder User Guide
• iMonitor User Guide
• Installation and Commissioning Guide for Remote Satellite Routers
• Features and Chassis Licensing Guide
• Software Installation Checklist/Software Upgrade Survey
• Link Budget Analysis Guide
• TRANSEC User Guide
• Technical Note on Setting Up Universal Line Cards (ULCs)
Trang 27System Overview
1 iDirect System Overview
This chapter presents a high-level overview of iDirect Networks It provides a sample iDirect network and describes the network architectures supported by iDirect
System Overview
An iDirect network is a satellite network with a Star topology in which a Time Division Multiplexed (TDM) broadcast downstream channel from a central hub location is shared by a number of remote sites Each remote transmits to the hub either on a shared Deterministic-TDMA (D-TDMA) upstream channel with dynamic timeplan slot assignments or on a dedicated SCPC return channel
The iDirect Hub equipment consists of one or more iDirect Hub Chassis with Universal Line Cards, one or more Protocol Processors (PP), a Network Management System (NMS) and the appropriate RF equipment Each remote site consists of an iDirect broadband satellite router and the appropriate external VSAT equipment
TDMA upstream carriers are configured in groups called Inroute Groups Multiple Inroute Groups can be associated with one downstream carrier Any remote configured to transmit to the hub on a TDMA upstream carrier is part of an Inroute Group The specific TDMA upstream carrier on which the remote transmits at any given time is determined dynamically during operation A remote that transmits on a dedicated SCPC return channel is not associated with
an Inroute Group Instead, the dedicated SCPC upstream carrier is directly assigned to the remote and to the hub line card that receives the carrier
Prior to iDX Release 3.2, all TDMA upstream carriers in an Inroute Group were required to have the same symbol rate, modulation and error coding With the introduction of Adaptive TDMA in iDX Release 3.2, the symbol rate and MODCOD of the carriers in an Inroute Group may vary from carrier to carrier Remotes in an Inroute Group move from carrier to carrier in real time based on network conditions Furthermore, with Adaptive TDMA, the individual carrier MODCODs can adjust over time to optimize network performance for changing network conditions Adaptive TDMA allows for significantly less fade margin in the network design and optimal use of upstream bandwidth during operation
Figure 1-1 on page 2 shows an example of an iDirect network The network consists of one downstream carrier; two Inroute Groups providing the TDMA return channels for a total of
1200 remotes; and three remotes transmitting dedicated SCPC return channels to the hub
Trang 28System Overview
Figure 1-1 Sample iDirect Network
iDirect software has flexible controls for configuring Quality of Service (QoS) and other traffic-engineered solutions based on end-user requirements and operator service plans Network configuration, control, and monitoring functions are provided by the integrated NMS.The iDirect software provides numerous features, including:
• Packet-based and network-based QoS, including Layer 2 and Layer 3 packet
classification
• TCP acceleration (IPv4)
• Multicast support
• End-to-end VLAN tagging
Layer 3 TCP/IP networks also support a long list of IP features, including DNS, DHCP, RIPv2, IGMP, GRE tunneling, and cRTP Layer 2 Ethernet-based networks provide Layer 3 protocol transparency and simplified operation for applications such as Virtual Private Networks
For a complete list of available features in all iDirect releases, see the iDirect Software Feature Matrix available on the TAC Web site.
Trang 29IP Network Architecture
IP Network Architecture
The examples in this section apply to traditional iDirect TCP/IP networks which transport IPV4 traffic over the satellite link Layer 2 networks, which transport Ethernet frames over satellite, are discussed in Layer 2 over Satellite on page 219 Since Layer 3 protocols are transparent to a Layer 2 network, a Layer 2 network can support Layer 3 protocols (such as IPv6 and BGP) that are not supported in an iDirect TCP/IP network
An iDirect network interfaces to the external world over Ethernet ports on the Remote Satellite Routers and the Protocol Processor servers at the hub The examples in Figure 1-2 on page 3, Figure 1-3 on page 4, and Figure 1-4 on page 5 illustrate the IP level configurations available to a Network Operator for Layer 3 networks
The iDirect system allows a mix of networks that use traditional IP routing and VLAN based configurations This provides support for customers with conflicting IP address ranges It also allows multiple independent customers at individual remote sites by configuring multiple VLANs on the same remote
Figure 1-2 iDirect IP Architecture – Multiple VLANs per Remote
Trang 30IP Network Architecture
Figure 1-3 iDirect IP Architecture – VLAN Spanning Remotes
Trang 31IP Network Architecture
Figure 1-4 iDirect IP Architecture – Classic IP Configuration
Trang 32IP Network Architecture
Trang 33• Improved inner coding: Low-Density Parity Coding
• Greater variety of modulations: QPSK, 8PSK, 16APSK, 32APSK
• Dynamic variation of the encoding on broadcast channel: Adaptive Coding and Modulation
These improvements lead to greater efficiencies and flexibility in the use of available bandwidth iDirect supports DVB-S2 in both TRANSEC and non-TRANSEC networks
DVB-S2 Key Concepts
A BBFRAME (Baseband Frame) is the basic unit of the DVB-S2 protocol Short frame size is supported
Each frame type is defined in the DVB-S2 standard in terms of the number of coded bits: short frames contain 16200 coded bits; long frames contain 64800 coded bits
MODCOD refers to the combinations of Modulation Types and Error Coding schemes supported by the
DVB-S2 standard The higher the MODCOD, the greater the number of bits per symbol (or bits per second per Hz (bps/Hz)) The modulation types specified by the standard are:
The DVB-S2 standard does not support every combination of modulation and coding DVB-S2 specifies the short frame MODCODs shown in Table 2-1 on page 8 In general, the lower the MODCOD, the more robust the error correction, and the lower the efficiency in bps/Hz The higher the MODCOD, the less robust the error correction, and the greater the efficiency in bps/Hz Long frames are not supported
Trang 34DVB-S2 Key Concepts
DVB-S2 defines three methods of applying modulation and coding to a data stream:
• ACM (Adaptive Coding and Modulation) specifies that every BBFRAME can be transmitted on a
different MODCOD Remotes receiving an ACM carrier cannot anticipate the MODCOD of the next BBFRAME A DVB-S2 demodulator such as those used by iDirect remotes must be designed to handle dynamic MODCOD variation
• CCM (Constant Coding and Modulation) specifies that every BBFRAME is transmitted at the same
MODCOD using long frames Long BBFRAMEs are not used in iDirect Instead, a constant MODCOD can be achieved by setting the Maximum and Minimum MODCODs of the outbound carrier to the
same value (See the iBuilder User Guide for details on configuring DVB-S2 carriers.)
Table 2-1 DVB-S2 Short Frame MODCODs
Trang 35DVB-S2 in iDirect
Figure 2-1 shows the bandwidth scale factor normalized to a maximum MODCOD 32APSK-8/9 For example, 8PSK Rate 3/5 requires 2.5 more bandwidth than 32APSK Rate 8/9 for a given information rate
Figure 2-1 Bandwidth Scale Factor normalized to max MODCOD 32APSK-8/9
DVB-S2 in iDirect
Beginning with iDX Release 3.2, iDirect only supports DVB-S2 downstream carriers Networks with iNFINITI downstream carriers are only supported in earlier releases All iDirect hardware supported in
this release can operate in a DVB-S2 network The iBuilder User Guide lists all available line card and
remote model types
iDirect DVB-S2 networks support ACM on the downstream carrier with all modulations up to 32APSK An iDirect DVB-S2 network always uses short DVB-S2 BBFRAMES iDirect also allows the Network Operator to configure multiple multicast streams and specify the multicast MODCOD of each stream
32APSK Support in DVB-S2 Downstream
Beginning with iDX Release 3.5.x, 32APSK Short Frame MODCODs are enabled on the DVB-S2 waveform extending the available outbound Adaptive Coding and Modulation (ACM) range This feature is
supported only on ULC-T/DLC-T Hub transmit linecards and X7, X1, and 9-series Remote platforms for the supported symbol rates of 1 to 451 Msps and Roll-off factors (ROF) of 52, 10, 15 and 20% All DVB-S2 capable remotes that only support 16APSK-8/9 maximum can co-exist in a network with 32APSK capable
Trang 3632APSK Support in DVB-S2 Downstream
terminals and are restricted in MODCOD accordingly For information on SNR threshold performance and available code-rates for 32APSK, see the iDX 3.5.x Link Budget Analysis (LBA) Guide On iDX pre-3.5.x Releases, XLC-11 and eM1D1 line cards support only up to 16APSK MODCODs, from 1 to 45 Msps
Remote LNB Consideration
It is recommended to provide high quality LNBs that have good frequency stability and phase noise over operational temperature range to meet the LBA performance of 32APSK MODCODs The LNB selection is critically important for meeting the 32APSK link performance The following guidelines are
recommended for all RF frequency bands:
LNB Frequency Stability (Overall): ± 3 ppm
LNB Phase Noise:
Mobility and Fade Considerations
Doppler effects due to terminal mobility affects the minimum symbol rate and constellations supported
in combination with RF performance of the link ACM SNR signaling for rain fade is extended to signal fades up to 20 dB operating point for 32APSK capable terminals The limit still remains at 15 dB for terminals that do not support 32APSK
For Low-Speed Communications on the Move (LS-COTM) inclusive of maritime, land-mobile and train terminals, restricted to 350 Km/hr and 1g acceleration, the minimum symbol rate supporting 32APSK constellation is 1 Msps
For High-Speed Communications on the Move (HS-COTM) aeronautical terminals with up to 1600 Km/hr and 2g acceleration, the minimum symbol rate is 5 Msps for supporting 32APSK constellation - Lower symbol rates down to 1 Msps can be used in certain HS-COTM applications with MODCODs restricted to 8PSK/16APSK range, based on RF performance of the link
Transponder Consideration
Linear and Non-linear distortions affects DVB-S2 LBA performance in single carrier use cases for full transponder operation Multiple carrier per transponder use cases are not affected usually by these distortions
1 A license is required on ULC-Ts to operate>15 Msps; DLC-Ts support up to 45 Msps without a license
2 Symbol rate restriction for 5% ROF mode at 10 Msps (min)
Trang 3732APSK Support in DVB-S2 Downstream
The Linear Pre-distortion (LPD) feature, introduced in iDX Release 3.5.x, will be able to mitigate the performance loss caused by transponder filters This feature equalizes the channel response to recover performance close to LBA threshold levels on a linear channel With LPD enabled, network performance improvement up to 1.5 dB in 16APSK and up to 3 dB in 32APSK modes can be achieved on a linear channel for the case of benign transponder models In addition, a complete loss of channel performance can be avoided on cases where linear distortions are severe, such as in certain older generation C and Ku-band transponders The LPD feature is only available on ULC-T/DLC-T line cards and are enabled
based on the channel conditions determined during commissioning of the network Contact your iDirect Sales Representative to analyze and assess the benefits of enabling LPD on your network.
DVB-S2 Downstream
A DVB-S2 downstream can only be configured as ACM An ACM downstream is not constrained to operate
at a fixed modulation and coding Instead, the modulation and coding of the downstream varies within a configurable range of MODCODs In iDirect, CCM is configured by limiting the MODCOD range to a single MODCOD
An iDirect DVB-S2 downstream contains a continuous stream of Physical Layer Frames (PLFRAMEs) The PLHEADER indicates the type of modulation and error correction coding used on the subsequent data It also indicates the data format and frame length Refer to Figure 2-2
Figure 2-2 Physical Layer Frames
The PLHEADER always uses /2 BPSK modulation Like most DVB-S2 systems, iDirect injects pilot symbols within the data stream The overhead of the DVB-S2 downstream varies between 2.65% and 3.85%.The symbol rate remains fixed on the DVB-S2 downstream Variation in throughput is realized through DVB-S2 support, and the variation of MODCODs in ACM Mode The maximum possible throughput of the DVB-S2 carrier (calculated at 45 Msym/s and highest MODCOD 32APSK 8/9) is approximately 185 Mbps Multiple protocol processors may be required to support high traffic to multiple remotes
iDirect uses DVB-S2 “Generic Streams” with a proprietary variation of the LEGS (Lightweight
Encapsulation for Generic Streams) protocol for encapsulation of downstream data between the DVB-S2 line cards and remotes LEGS maximizes the efficiency of data packing into BBFRAMES on the
downstream For example, if a time plan only takes up 80% of a BBFRAME, the LEGS protocol allows the line card to include a portion of another packet that is ready for transmission in the same frame This results in maximum use of the downstream bandwidth
PLHEADER: signals MODCOD and frame length (always S/2 BPSK)
Pilot symbols:
unmodulated carrier
Data symbols: QPSK, 8PSK, 16APSK, or 32APSK
Trang 3832APSK Support in DVB-S2 Downstream
ACM Operation
Adaptive Coding and Modulation (ACM) allows remotes operating in better signal conditions to receive data on higher MODCODs by varying the MODCOD of data targeted to each remote to match its current receive capabilities
Not all data is sent to each remote at its most efficient MODCOD Important system information (such as time plan messages), as well as broadcast traffic, is transmitted at the minimum MODCOD configured for the outbound carrier This allows all remotes in the network, even those operating at the minimum MODCOD, to receive this information reliably
The protocol processor determines the maximum MODCOD for all data sent to the DVB-S2 line card for transmission over the outbound carrier However, the line card does not necessarily respect these MODCOD assignments In the interest of downstream efficiency, some data scheduled for a high MODCOD may be transmitted at a lower one as an alternative to inserting padding bytes into a BBFRAME When assembling a BBFRAME for transmission, the line card first packs all available data for the chosen MODCOD into the frame If there is space left in the BBFRAME, and no data left for transmission at that MODCOD, the line card attempts to pack the remainder of the frame with data for higher MODCODs This takes advantage of the fact that a remote can demodulate any MODCOD in the range between the carrier’s minimum MODCOD and the remote current maximum MODCOD
The maximum MODCOD of a remote is based on the latest Signal-to-Noise Ratio (SNR) reported by the remote to the protocol processor The SNR thresholds per MODCOD are determined during hardware qualification for each remote model type The Spectral Efficiency of iDirect remotes at the threshold
SNR for each MODCOD is documented in the iDirect Link Budget Analysis Guide.
The hub adjusts the MODCODs of the transmissions to the remotes by means of the feedback loop shown
in Figure 2-3 on page 13 Each remote continually measures its downstream SNR and reports the current value to the protocol processor When the protocol processor assigns data to an individual remote, it uses the last reported SNR value to determine the highest MODCOD on which that remote can receive data without exceeding a specified BER The protocol processor includes this information when sending outbound data to the line card The line card then adjusts the MODCOD of the BBFRAMES to the targeted remotes accordingly
NOTE: The line card may adjust the MODCOD of the BBFRAMEs downward for
downstream packing efficiency
Trang 3932APSK Support in DVB-S2 Downstream
Figure 2-3 and Figure 2-4 show the operation of the SNR feedback loop and the behavior of the line card and remote during fast fade conditions Figure 2-3 shows the basic SNR reporting loop described above
Figure 2-3 Feedback Loop from Remote to Protocol Processor
Figure 2-4page 13 shows the back-off mechanism that exists between the line card and protocol
processor to prevent data loss The protocol processor decreases the maximum data sent to the line card for transmission based on a measure of the number of remaining untransmitted bytes on the line card These bytes are scaled according to the MODCOD on which they are to be transmitted, since bytes destined to be transmitted at lower MODCODs will take longer to transmit than bytes destined to be transmitted on a higher MODCODs
Figure 2-4 Feedback Loop with Back-Off from Line Card to Protocol Processor
Remote
Rx Line card
SNR measured and reported to PP
New MODCOD Incoming user
data
internal queue SNR compared to
SNR threshold:
new MODCOD selected
Downstream throughput (varies based on MODCOD assigned )
Remote
Rx Line Card
SNR measured and reported to PP
New MODCOD Incoming user
data
Tx ine card queue too full? Allocate less user data
internal queue SNR compared to
SNR threshold:
New MODCOD selected
Tx line card reports internal queue fullness
to PP
Reduction in downstream data
Downstream throughput (varies based on MODCOD assigned)
Trang 4032APSK Support in DVB-S2 Downstream
Quality of Service in DVB-S2 ACM Networks
iDirect QoS for DVB-S2 downstream carriers is basically identical to QoS for fixed MODCOD downstream carriers (See QoS Implementation Principles on page 65.) However, with DVB-S2 in ACM Mode, the same amount of user data (in bits per second) occupies more or less downstream bandwidth, depending on the MODCOD at which it is transmitted This is true because user data transmitted at a higher MODCOD requires less bandwidth than it does at a lower MODCOD
When configuring QoS in iBuilder, a Network Operator can define a Maximum Information Rate (MIR)
and/or a Committed Information Rate (CIR) at various levels of the QoS tree (See the iBuilder User Guide for definitions of CIR and MIR.) For an ACM outbound, the amount of bandwidth granted for a
configured CIR or MIR is affected by both the MODCOD that the remote is currently receiving and a number of parameters configurable in iBuilder The remainder of this section discusses the various parameters and options that affect DVB-S2 bandwidth allocation and how they affect the system performance
Remote Nominal MODCOD
The Network Operator can configure a Nominal MODCOD for DVB-S2 remotes operating in ACM mode The Nominal MODCOD is the Reference Operating Point (ROP) for the remote By default, a remote Nominal MODCOD is equal to the DVB-S2 carrier’s Maximum MODCOD The Nominal MODCOD is typically determined by the link budget but may be adjusted after the remote is operational
In a fixed network environment, the Nominal MODCOD is typically chosen to be the Clear Sky MODCOD of the remote In a mobile network where the Clear Sky MODCOD depends on the position of the remote terminal, the Nominal MODCOD may be any point in the beam coverage at which the service provider chooses to guarantee the CIR
The CIR and MIR granted to the remote are limited by the remote Nominal MODCOD The remote is allowed to operate at MODCODs higher than the Nominal MODCOD (as long as it does not exceed the configured Remote Maximum MODCOD described below), but is not granted additional higher CIR or MIR when operating above the Nominal MODCOD
Remote Maximum MODCOD
The Network Operator can also configure a Maximum MODCOD for DVB-S2 remotes operating in ACM mode By default, a remote Maximum MODCOD is equal to the DVB-S2 carrier’s Maximum MODCOD iBuilder allows the operator to limit the Maximum MODCOD for a remote to a value lower than the DVB-S2 carrier’s Maximum MODCOD and higher than or equal to the remote Nominal MODCOD This is important if the network link budget supports higher MODCODs but some remote LNBs do not have the phase stability required for the higher MODCODs For example, a DRO LNB cannot support 16APSK due to phase instability at higher MODCODs
Note that a remote Maximum MODCOD is not the same as a remote Nominal MODCOD The remote is allowed to operate above its Nominal MODCOD as long as it does not exceed the remote Maximum MODCOD A remote is never allowed to operate above its Maximum MODCOD
Fixed Bandwidth Operation
During a rain fade, the CIR or MIR granted to a remote are scaled down based on the remote Nominal MODCOD This provides a graceful degradation of CIR and MIR during the fade while consuming the same satellite bandwidth as at the Nominal MODCOD