TCP/IP 路由技术 （第2卷）（英文版）
Part I Exterior Gateway Protocols
Chapter 1 Exterior Gateway Protocol
The Origins of EGP
Operation of EGP
EGP Topology Issues
EGP Functions
EGP Message Formats
Shortcomings of EGP
Configuring EGP
Case Study: An EGP Stub Gateway
查看完整
Chapter 1 Exterior Gateway Protocol
The Origins of EGP
Operation of EGP
EGP Topology Issues
EGP Functions
EGP Message Formats
Shortcomings of EGP
Configuring EGP
Case Study: An EGP Stub Gateway
查看完整
Jeff Doyle，CCIE #1919， is a Professional Services Consultant with Juniper Networks， Inc. in Denver，Colorado. Specializing in IP routing protocols and MPLS Traffic Engineering， Jeff has helped design andimplement large-scale Internet service provider networks throughout North America， Europe， and Asia.Jeff has also lectured on advanced networking technologies at service provider forums such as the NorthAmerican Network Opera…
查看完整
查看完整
《TCP/IP 路由技术 (第2卷)(英文版)(精)》深入系统地阐述了TCP/IP路由技术，内容包括几种重要的网络协议，如外部网关协议（EGP）、边界网关协议（BGP4），以及相应的高级IP路由技术与应用——网络地址转换、IP组播路由技术、IPv6技术、路由器管理等。《TCP/IP 路由技术 (第2卷)(英文版)(精)》共分9章，首先介绍并讨论了有关主题的基本原理，接着是设计用来展示实际网络环境中相关概念的一系列配置范例，最后提供给读者经实践验证过的故障排除方法以解决网络可能会出现的问题。重点介绍了自治系统之间的路由选择策略以及诸如组播和IPv6等更具挑战性的路由选择和实施技术。
《TCP/IP 路由技术 (第2卷)(英文版)(精)》内容全面，可读性强，含有协议配置、网络实施、故障排除等方面的大量实例，是备战CCIE认证考试的经典之作，适合准备参加CCIE考试的人员、网络与通信系统工程技术人员阅读。
《TCP/IP 路由技术 (第2卷)(英文版)(精)》内容全面，可读性强，含有协议配置、网络实施、故障排除等方面的大量实例，是备战CCIE认证考试的经典之作，适合准备参加CCIE考试的人员、网络与通信系统工程技术人员阅读。
Part I Exterior Gateway Protocols
Chapter 1 Exterior Gateway Protocol
The Origins of EGP
Operation of EGP
EGP Topology Issues
EGP Functions
EGP Message Formats
Shortcomings of EGP
Configuring EGP
Case Study: An EGP Stub Gateway
Case Study: An EGP Core Gateway
Case Study: Indirect Neighbors
Case Study: Default Routes
Troubleshooting EGP
Interpreting the Neighbor Table
Case Study: Converging at the Speed of Syrup
End Notes
Looking Ahead
Review Questions
Configuration Exercises
Troubleshooting Exercise
Chapter 2 Introduction to Border Gateway Protocol 4
Classless Interdomain Routing
A Summarization Summary
Classless Routing
Summarization: The Good, the Bad, and the Asymmetric
The Internet: Still Hierarchical After All These Years
CIDR: Reducing Routing Table Explosion
CIDR: Reducing Class B Address Space Depletion
Difficulties with CIDR
Who Needs BGP?
A Single-Homed Autonomous System
Multihoming to a Single Autonomous System
Multihoming to Multiple Autonomous Systems
A Note on “Load Balancing”
BGP Hazards
BGP Basics
BGP Message Types
The BGP Finite State Machine
Path Attributes
Administrative Weight
AS_SET
The BGP Decision Process
Route Dampening
IBGP and IGP Synchronization
Managing Large-Scale BGP Peering
Peer Groups
Communities
Route Reflectors
Confederations
BGP Message Formats
The Open Message
The Update Message
The Keepalive Message
The Notification Message
End Notes
Looking Ahead
Recommended Reading
Review Questions
Chapter 3 Configuring and Troubleshooting Border Gateway Protocol 4
Basic BGP Configuration
Case Study: Peering BGP Routers
Case Study: Injecting IGP Routes into BGP
Case Study: Injecting BGP Routes into an IGP
Case Study: IBGP without an IGP
Case Study: IBGP Over an IGP
Case Study: EBGP Multihop
Case Study: Aggregate Routes
Managing BGP Connections
Routing Policies
Resetting BGP Connections
Case Study: Filtering Routes by NLRI
Case Study: Filtering Routes by AS_PATH
Case Study: Filtering with Route Maps
Case Study: Administrative Weights
Case Study: Administrative Distances and Backdoor Routes
Case Study: Using the LOCAL_PREF Attribute 241
Case Study: Using the MULTI_EXIT_DISC Attribute
Case Study: Prepending the AS_PATH
Case Study: Route Tagging
Case Study: Route Dampening
Large-Scale BGP
Case Study: BGP Peer Groups
Case Study: BGP Communities
Case Study: Private AS Numbers
Case Study: BGP Confederations
Case Study: Route Reflectors
Looking Ahead
Recommended Reading
Command Summary
Configuration Exercises
Troubleshooting Exercises
Part II Advanced IP Routing Issues
Chapter 4 Network Address Translation
Operation of NAT
Basic NAT Concepts
NAT and IP Address Conservation
NAT and ISP Migration
NAT and Multihomed Autonomous Systems
Port Address Translation
NAT and TCP Load Distribution
NAT and Virtual Servers
NAT Issues
Header Checksums
Fragmentation
Encryption
Security
Protocol-Specific Issues
Configuring NAT
Case Study: Static NAT
Case Study: Dynamic NAT
Case Study: A Network Merger
Case Study: ISP Multihoming with NAT
Port Address Translation
Case Study: TCP Load Balancing
Case Study: Service Distribution
Troubleshooting NAT
End Note
Looking Ahead
Command Summary
Configuration Exercises
Troubleshooting Exercises
Chapter 5 Introduction to IP Multicast Routing
Requirements for IP Multicast
Multicast IP Addresses
Group Membership Concepts
Internet Group Management Protocol (IGMP)
Cisco Group Membership Protocol (CGMP)
Multicast Routing Issues
Multicast Forwarding
Multicast Routing
Sparse Versus Dense Topologies
Implicit Joins Versus Explicit Joins
Source-Based Trees Versus Shared Trees
Multicast Scoping
Operation of the Distance Vector Multicast Routing Protocol (DVMRP)
Neighbor Discovery and Maintenance
The DVMRP Routing Table
DVMRP Packet Forwarding
DVMRP Message Formats
Operation of Multicast OSPF (MOSPF)
MOSPF Basics
Inter-Area MOSPF
Inter-AS MOSPF
MOSPF Extension Formats
Operation of Core-Based Trees (CBT)
CBT Basics
Finding the Core
CBT Designated Routers
Member and Nonmember Sources
CBT Message Formats
Introduction to Protocol Independent Multicast (PIM)
Operation of Protocol Independent Multicast, Dense Mode (PIM-DM)
PIM-DM Basics
Prune Overrides
Unicast Route Changes
PIM-DM-Designated Routers
PIM Forwarder Election
Operation of Protocol Independent Multicast, Sparse Mode (PIM-SM)
PIM-SM Basics
Finding the Rendezvous Point
PIM-SM and Shared Trees
Source Registration
PIM-SM and Shortest Path Trees
PIMv2 Message Formats
End Notes
Looking Ahead
Recommended Reading
Command Summary
Review Questions
Chapter 6 Configuring and Troubleshooting IP Multicast Routing
Configuring IP Multicast Routing
Case Study: Configuring Protocol-Independent Multicast, Dense Mode (PIM-DM)
Configuring Protocol-Independent Multicast, Sparse Mode (PIM-SM)
Case Study: Multicast Load Sharing
Troubleshooting IP Multicast Routing
Using mrinfo
Using mtrace and mstat
Looking Ahead
Configuration Exercises
Troubleshooting Exercises
Chapter 7 Large-Scale IP Multicast Routing
Multicast Scoping
Case Study: Multicasting Across Non-Multicast Domains
Connecting to DVMRP Networks
Inter-AS Multicasting
Multiprotocol Extensions for BGP (MBGP)
Operation of Multicast Source Discovery Protocol (MSDP)
MSDP Message Formats
Case Study: Configuring MBGP
Case Study: Configuring MSDP
Case Study: MSDP Mesh Groups
Case Study: Anycast RP
Case Study: MSDP Default Peers
Command Summary
End Notes
Looking Ahead
Review Questions
Chapter 8 IP Version 6
Design Goals of IPv6
Improve Scalability
Ease of Configuration
Security
Current State of IPv6
IPv6 Specification (RFCs)
Vendor Support
Implementations
IPv6 Packet Format
The IPv6 Address
Address Structure
IPv6 Header
IPv6 Functionality
Enabling IPv6 Capability on a Cisco Router
ICMPv6
Neighbor Discovery
Autoconfiguration
Routing
The Anycast Process
Multicast
Quality of Service
Transition from IPv4 to IPv6
Dual Stacks
DNS
IPv6 Tunneled in IPv4
Network Address Translation-Protocol Translation
End Notes
Looking Ahead
Recommended Reading
Review Questions
Chapter Bibliography
Chapter 9 Router Management
Policies and Procedure Definition
Service Level Agreements
Change Management
Escalation Procedures
Updating Policies
Simple Network Management Protocol
Overview of SNMP
CiscoWorks
Router Configuration for SNMP
RMON
Overview of RMON
Router Configuration for RMON
Logging
Syslog
Overview of Syslog
Router Configuration for Syslog
Network Time Protocol
Overview of NTP
Router Configuration for NTP
Accounting
IP Accounting
NetFlow
Configuration Management
Fault Management
Performance Management
Security Management
Password Types and Encryption
Controlling Interactive Access
Minimizing Risks of Denial-of-Service Attacks
TACACS+
RADIUS
Secure Shell
Designing Servers to Support Management Processes
Network Robustness
HSRP
Lab
Recommended Reading
End Notes
Looking Ahead
Command Summary
Review Questions
Configuration Exercises
Bibliography
Part III Appendixes
Appendix A The show ip bgp neighbors Display
Appendix B A Regular-Expression Tutorial
Literals and Metacharacters
Delineation: Matching the Start and End of Lines
Bracketing: Matching a Set of Characters 816
Negating: Matching Everything Except a Set of Characters
Wildcard: Matching Any Single Character
Alternation: Matching One of a Set of Characters
Optional Characters: Matching a Character That May or May Not Be There
Repetition: Matching a Number of Repeating Characters
Boundaries: Delineating Literals
Putting It All Together: A Complex Example
Recommended Reading
Appendix C Reserved Multicast Addresses
Internet Multicast Addresses
References
People
Appendix D Answers to Review Questions
Answers to Chapter 1 Review Questions
Answers to Chapter 2 Review Questions
Answers to Chapter 5 Review Questions
Answers to Chapter 7 Review Questions
Answers to Chapter 8 Review Questions
Answers to Chapter 9 Review Questions
Appendix E Answers to Configuration Exercises
Answers to Chapter 1 Configuration Exercises
Answers to Chapter 3 Configuration Exercises
Answers to Chapter 4 Configuration Exercises
Answers to Chapter 6 Configuration Exercises
Answers to Chapter 9 Configuration Exercises
Appendix F Answers to Troubleshooting Exercises
Answer to Chapter 1 Troubleshooting Exercise
Answers to Chapter 3 Troubleshooting Exercises
Answers to Chapter 4 Troubleshooting Exercises
Answers to Chapter 6 Troubleshooting Exercises
Index
^ 收 起
Chapter 1 Exterior Gateway Protocol
The Origins of EGP
Operation of EGP
EGP Topology Issues
EGP Functions
EGP Message Formats
Shortcomings of EGP
Configuring EGP
Case Study: An EGP Stub Gateway
Case Study: An EGP Core Gateway
Case Study: Indirect Neighbors
Case Study: Default Routes
Troubleshooting EGP
Interpreting the Neighbor Table
Case Study: Converging at the Speed of Syrup
End Notes
Looking Ahead
Review Questions
Configuration Exercises
Troubleshooting Exercise
Chapter 2 Introduction to Border Gateway Protocol 4
Classless Interdomain Routing
A Summarization Summary
Classless Routing
Summarization: The Good, the Bad, and the Asymmetric
The Internet: Still Hierarchical After All These Years
CIDR: Reducing Routing Table Explosion
CIDR: Reducing Class B Address Space Depletion
Difficulties with CIDR
Who Needs BGP?
A Single-Homed Autonomous System
Multihoming to a Single Autonomous System
Multihoming to Multiple Autonomous Systems
A Note on “Load Balancing”
BGP Hazards
BGP Basics
BGP Message Types
The BGP Finite State Machine
Path Attributes
Administrative Weight
AS_SET
The BGP Decision Process
Route Dampening
IBGP and IGP Synchronization
Managing Large-Scale BGP Peering
Peer Groups
Communities
Route Reflectors
Confederations
BGP Message Formats
The Open Message
The Update Message
The Keepalive Message
The Notification Message
End Notes
Looking Ahead
Recommended Reading
Review Questions
Chapter 3 Configuring and Troubleshooting Border Gateway Protocol 4
Basic BGP Configuration
Case Study: Peering BGP Routers
Case Study: Injecting IGP Routes into BGP
Case Study: Injecting BGP Routes into an IGP
Case Study: IBGP without an IGP
Case Study: IBGP Over an IGP
Case Study: EBGP Multihop
Case Study: Aggregate Routes
Managing BGP Connections
Routing Policies
Resetting BGP Connections
Case Study: Filtering Routes by NLRI
Case Study: Filtering Routes by AS_PATH
Case Study: Filtering with Route Maps
Case Study: Administrative Weights
Case Study: Administrative Distances and Backdoor Routes
Case Study: Using the LOCAL_PREF Attribute 241
Case Study: Using the MULTI_EXIT_DISC Attribute
Case Study: Prepending the AS_PATH
Case Study: Route Tagging
Case Study: Route Dampening
Large-Scale BGP
Case Study: BGP Peer Groups
Case Study: BGP Communities
Case Study: Private AS Numbers
Case Study: BGP Confederations
Case Study: Route Reflectors
Looking Ahead
Recommended Reading
Command Summary
Configuration Exercises
Troubleshooting Exercises
Part II Advanced IP Routing Issues
Chapter 4 Network Address Translation
Operation of NAT
Basic NAT Concepts
NAT and IP Address Conservation
NAT and ISP Migration
NAT and Multihomed Autonomous Systems
Port Address Translation
NAT and TCP Load Distribution
NAT and Virtual Servers
NAT Issues
Header Checksums
Fragmentation
Encryption
Security
Protocol-Specific Issues
Configuring NAT
Case Study: Static NAT
Case Study: Dynamic NAT
Case Study: A Network Merger
Case Study: ISP Multihoming with NAT
Port Address Translation
Case Study: TCP Load Balancing
Case Study: Service Distribution
Troubleshooting NAT
End Note
Looking Ahead
Command Summary
Configuration Exercises
Troubleshooting Exercises
Chapter 5 Introduction to IP Multicast Routing
Requirements for IP Multicast
Multicast IP Addresses
Group Membership Concepts
Internet Group Management Protocol (IGMP)
Cisco Group Membership Protocol (CGMP)
Multicast Routing Issues
Multicast Forwarding
Multicast Routing
Sparse Versus Dense Topologies
Implicit Joins Versus Explicit Joins
Source-Based Trees Versus Shared Trees
Multicast Scoping
Operation of the Distance Vector Multicast Routing Protocol (DVMRP)
Neighbor Discovery and Maintenance
The DVMRP Routing Table
DVMRP Packet Forwarding
DVMRP Message Formats
Operation of Multicast OSPF (MOSPF)
MOSPF Basics
Inter-Area MOSPF
Inter-AS MOSPF
MOSPF Extension Formats
Operation of Core-Based Trees (CBT)
CBT Basics
Finding the Core
CBT Designated Routers
Member and Nonmember Sources
CBT Message Formats
Introduction to Protocol Independent Multicast (PIM)
Operation of Protocol Independent Multicast, Dense Mode (PIM-DM)
PIM-DM Basics
Prune Overrides
Unicast Route Changes
PIM-DM-Designated Routers
PIM Forwarder Election
Operation of Protocol Independent Multicast, Sparse Mode (PIM-SM)
PIM-SM Basics
Finding the Rendezvous Point
PIM-SM and Shared Trees
Source Registration
PIM-SM and Shortest Path Trees
PIMv2 Message Formats
End Notes
Looking Ahead
Recommended Reading
Command Summary
Review Questions
Chapter 6 Configuring and Troubleshooting IP Multicast Routing
Configuring IP Multicast Routing
Case Study: Configuring Protocol-Independent Multicast, Dense Mode (PIM-DM)
Configuring Protocol-Independent Multicast, Sparse Mode (PIM-SM)
Case Study: Multicast Load Sharing
Troubleshooting IP Multicast Routing
Using mrinfo
Using mtrace and mstat
Looking Ahead
Configuration Exercises
Troubleshooting Exercises
Chapter 7 Large-Scale IP Multicast Routing
Multicast Scoping
Case Study: Multicasting Across Non-Multicast Domains
Connecting to DVMRP Networks
Inter-AS Multicasting
Multiprotocol Extensions for BGP (MBGP)
Operation of Multicast Source Discovery Protocol (MSDP)
MSDP Message Formats
Case Study: Configuring MBGP
Case Study: Configuring MSDP
Case Study: MSDP Mesh Groups
Case Study: Anycast RP
Case Study: MSDP Default Peers
Command Summary
End Notes
Looking Ahead
Review Questions
Chapter 8 IP Version 6
Design Goals of IPv6
Improve Scalability
Ease of Configuration
Security
Current State of IPv6
IPv6 Specification (RFCs)
Vendor Support
Implementations
IPv6 Packet Format
The IPv6 Address
Address Structure
IPv6 Header
IPv6 Functionality
Enabling IPv6 Capability on a Cisco Router
ICMPv6
Neighbor Discovery
Autoconfiguration
Routing
The Anycast Process
Multicast
Quality of Service
Transition from IPv4 to IPv6
Dual Stacks
DNS
IPv6 Tunneled in IPv4
Network Address Translation-Protocol Translation
End Notes
Looking Ahead
Recommended Reading
Review Questions
Chapter Bibliography
Chapter 9 Router Management
Policies and Procedure Definition
Service Level Agreements
Change Management
Escalation Procedures
Updating Policies
Simple Network Management Protocol
Overview of SNMP
CiscoWorks
Router Configuration for SNMP
RMON
Overview of RMON
Router Configuration for RMON
Logging
Syslog
Overview of Syslog
Router Configuration for Syslog
Network Time Protocol
Overview of NTP
Router Configuration for NTP
Accounting
IP Accounting
NetFlow
Configuration Management
Fault Management
Performance Management
Security Management
Password Types and Encryption
Controlling Interactive Access
Minimizing Risks of Denial-of-Service Attacks
TACACS+
RADIUS
Secure Shell
Designing Servers to Support Management Processes
Network Robustness
HSRP
Lab
Recommended Reading
End Notes
Looking Ahead
Command Summary
Review Questions
Configuration Exercises
Bibliography
Part III Appendixes
Appendix A The show ip bgp neighbors Display
Appendix B A Regular-Expression Tutorial
Literals and Metacharacters
Delineation: Matching the Start and End of Lines
Bracketing: Matching a Set of Characters 816
Negating: Matching Everything Except a Set of Characters
Wildcard: Matching Any Single Character
Alternation: Matching One of a Set of Characters
Optional Characters: Matching a Character That May or May Not Be There
Repetition: Matching a Number of Repeating Characters
Boundaries: Delineating Literals
Putting It All Together: A Complex Example
Recommended Reading
Appendix C Reserved Multicast Addresses
Internet Multicast Addresses
References
People
Appendix D Answers to Review Questions
Answers to Chapter 1 Review Questions
Answers to Chapter 2 Review Questions
Answers to Chapter 5 Review Questions
Answers to Chapter 7 Review Questions
Answers to Chapter 8 Review Questions
Answers to Chapter 9 Review Questions
Appendix E Answers to Configuration Exercises
Answers to Chapter 1 Configuration Exercises
Answers to Chapter 3 Configuration Exercises
Answers to Chapter 4 Configuration Exercises
Answers to Chapter 6 Configuration Exercises
Answers to Chapter 9 Configuration Exercises
Appendix F Answers to Troubleshooting Exercises
Answer to Chapter 1 Troubleshooting Exercise
Answers to Chapter 3 Troubleshooting Exercises
Answers to Chapter 4 Troubleshooting Exercises
Answers to Chapter 6 Troubleshooting Exercises
Index
^ 收 起
Jeff Doyle，CCIE #1919， is a Professional Services Consultant with Juniper Networks， Inc. in Denver，Colorado. Specializing in IP routing protocols and MPLS Traffic Engineering， Jeff has helped design andimplement large-scale Internet service provider networks throughout North America， Europe， and Asia.Jeff has also lectured on advanced networking technologies at service provider forums such as the NorthAmerican Network Operators Group （NANOG） and the Asia Pacific Regional Internet Conference onOperational Technologies （APRICOT）. Prior to joining Juniper Networks， Jeff was a Senior Network Sys-tems Consultant with International Network Services. Jeff can be contacted at jeff@juniper.net.Jennifer DeHaven Carroll， is a principal consultant with Lucent technologies and is a Cisco CertifiedInternetwork Expert （CCIE # 1402）. She has planned， designed， and implemented many large networksover the past 13 years. She has also developed and taught theory and Cisco implementation classes on allIP routing protocols. Jenny can be reached at jennifer.carroll@ieee.org.About the Technical Reviewers
Henry Benjamin， CCIE #4695， CCNA， CCDA， B. Eng.， is a Cisco certified Interuet Expert and an IT Net-work Design Engineer for Cisco Systems， Inc. He has more than eight years of experience in Cisco net-works， including planning， designing， and implementing large IP networks running IGRP， EIGRP， andOSPF. Currently Henry is working for the IT design team internally at Cisco in Sydney， Australia. Henryholds a Bachelor of Engineering degree from Sydney University.Peter J. Moyer， CCIE #3286， is a Professional Services Consultant for Juniper Networks， where hedesigns and implements large-scale ISP networks. In addition to his consulting work， Peter has developedand delivered advanced IP training courses and IP network design seminars to Juniper customers andpartners. He has presented at networking conferences on such advanced topics as MPLS. Before joiningJuniper， Peter was a Senior Network Consultant for International Network Services （INS）， where hedesigned and implemented large-scale enterprise networks. Peter holds a Bachelor of Science degree inComputer and Information Science from the University of Maryland.
^ 收 起
Henry Benjamin， CCIE #4695， CCNA， CCDA， B. Eng.， is a Cisco certified Interuet Expert and an IT Net-work Design Engineer for Cisco Systems， Inc. He has more than eight years of experience in Cisco net-works， including planning， designing， and implementing large IP networks running IGRP， EIGRP， andOSPF. Currently Henry is working for the IT design team internally at Cisco in Sydney， Australia. Henryholds a Bachelor of Engineering degree from Sydney University.Peter J. Moyer， CCIE #3286， is a Professional Services Consultant for Juniper Networks， where hedesigns and implements large-scale ISP networks. In addition to his consulting work， Peter has developedand delivered advanced IP training courses and IP network design seminars to Juniper customers andpartners. He has presented at networking conferences on such advanced topics as MPLS. Before joiningJuniper， Peter was a Senior Network Consultant for International Network Services （INS）， where hedesigned and implemented large-scale enterprise networks. Peter holds a Bachelor of Science degree inComputer and Information Science from the University of Maryland.
^ 收 起
《TCP/IP 路由技术 (第2卷)(英文版)(精)》深入系统地阐述了TCP/IP路由技术，内容包括几种重要的网络协议，如外部网关协议（EGP）、边界网关协议（BGP4），以及相应的高级IP路由技术与应用——网络地址转换、IP组播路由技术、IPv6技术、路由器管理等。《TCP/IP 路由技术 (第2卷)(英文版)(精)》共分9章，首先介绍并讨论了有关主题的基本原理，接着是设计用来展示实际网络环境中相关概念的一系列配置范例，最后提供给读者经实践验证过的故障排除方法以解决网络可能会出现的问题。重点介绍了自治系统之间的路由选择策略以及诸如组播和IPv6等更具挑战性的路由选择和实施技术。
《TCP/IP 路由技术 (第2卷)(英文版)(精)》内容全面，可读性强，含有协议配置、网络实施、故障排除等方面的大量实例，是备战CCIE认证考试的经典之作，适合准备参加CCIE考试的人员、网络与通信系统工程技术人员阅读。
《TCP/IP 路由技术 (第2卷)(英文版)(精)》内容全面，可读性强，含有协议配置、网络实施、故障排除等方面的大量实例，是备战CCIE认证考试的经典之作，适合准备参加CCIE考试的人员、网络与通信系统工程技术人员阅读。
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