Introduction
CHAPTER 1: Network Technologies, Topologies, and Types
Wired and Wireless Network Topologies
Bus Topology
Ring Topology
Star Topology (Hub-and-Spoke)
Mesh Topology
Hybrid Topology
Bringing Wireless to a Topology
Infrastructure Wireless Topology
Ad Hoc Wireless Topology
Wireless Mesh Topology
Network Types and Characteristics
To Server or Not
LANs
WLANs
WANs
MANs
CANs
SANs
PANs
SDWANs
MPLS
mGRE
Network Links and Concepts
DSL Internet Access
Cable Broadband
The Public Switched Telephone Network
Leased Lines
T3 Lines
Metro-Optical
Satellite Internet Access
Termination Points
Demarc, Demarc Extension, and Smart Jacks
CSUs/DSUs
Verify Wiring Installation and Termination
Virtual Networking
What's Next?
CHAPTER 2: Models, Ports, Protocols, and Network Services
The OSI Networking Model
The OSI Seven-Layer Model
Physical Layer (Layer 1)
Data Link Layer (Layer 2)
Network Layer (Layer 3)
Transport Layer (Layer 4)
Session Layer (Layer 5)
Presentation Layer (Layer 6)
Application Layer (Layer 7)
OSI Model Summary
Comparing OSI to the Four-Layer TCP/IP Model
Identifying the OSI Layers at Which Various Network Components Operate
Data Encapsulation/Decapsulation and OSI
Ports and Protocols
Connection-Oriented Protocols Versus Connectionless Protocols
Internet Protocol
Transmission Control Protocol
How TCP Works
User Datagram Protocol
Internet Control Message Protocol
IPSec
Generic Routing Encapsulation
File Transfer Protocol
Secure Shell
Secure File Transfer Protocol
Telnet
Simple Mail Transfer Protocol
Domain Name System (DNS)
Dynamic Host Configuration Protocol (DHCP)
Trivial File Transfer Protocol
Hypertext Transfer Protocol
Network Time Protocol (NTP)
Post Office Protocol Version 3/Internet Message Access Protocol Version 4
Simple Network Management Protocol
Components of SNMP
SNMP Management Systems
SNMP Agents
Management Information Bases
SNMP Communities
SNMPv3
Lightweight Directory Access Protocol
Hypertext Transfer Protocol Secure
Server Message Block
Syslog
SMTP TLS
LDAPS
IMAP over SSL
POP3 over SSL
SQL, SQLnet, and MySQL
Remote Desktop Protocol
Session Initiation Protocol
Understanding Port Functions
Network Services
Domain Name Service (DNS)
The DNS Namespace
Types of DNS Entries
DNS Records
DNS in a Practical Implementation
Dynamic Host Configuration Protocol
The DHCP Process
DHCP and DNS Suffixes
DHCP Relays and IP Helpers
Network Time Protocol
What's Next?
CHAPTER 3: Addressing, Routing, and Switching
IP Addressing
IPv4
IP Address Classes
Subnet Mask Assignment
Subnetting
Identifying the Differences Between IPv4 Public and Private Networks
Private Address Ranges
Classless Interdomain Routing
Default Gateways
Virtual IP
IPv4 Address Types
Unicast Address
Broadcast Address
Multicast
IPv6 Addressing
Where Have All the IPv4 Addresses Gone?
Identifying IPv6 Addresses
IPv6 Address Types
Global Unicast Addresses
Link-Local Addresses
Site-Local Addresses
Neighbor Discovery
Comparing IPv4 and IPv6 Addressing
Assigning IP Addresses
Static Addressing
Dynamic Addressing
BOOT Protocol (BOOTP)
Automatic Private IP Addressing
Identifying MAC Addresses
NAT and PAT
NAT
PAT
SNAT
DNAT
Managing Routing and Switching
The Default Gateway
Routing Tables
Static Routing
Default Route
Switching Methods
Packet Switching
Circuit Switching
Comparing Switching Methods
Dynamic Routing
Distance-Vector Routing
Link-State Routing
Hybrid Routing Protocols
Network Traffic
Routing Metrics
Virtual Local-Area Networks
VLAN Membership
VLAN Segmentation
The Spanning Tree Protocol
Interface Configuration and Switch Management
MDI-X
Trunking
Port Mirroring
Port Authentication
Power over Ethernet (PoE and PoE+)
MAC Address Table
Switch Management
Managed and Unmanaged
Quality of Service
Traffic Shaping
Access Control Lists
ARP and RARP
What's Next?
CHAPTER 4: Network Implementations
Common Networking Devices
Firewall
IDS/IPS
Router
Switch
Hub and Switch Cabling
Multilayer Switch
Hub
Bridge
DSL and Cable Modems
Access Point
Media Converter
Voice Gateway
Repeater
Wireless LAN Controller
Load Balancer
Proxy Server
VPN Concentrators and Headends
Networked Devices
Networking Architecture
Three-Tiered Architecture
Core Layer
Distribution/Aggregation Layer
Access/Edge Layer
Software-Defined Networking
Application Layer
Control Layer
Infrastructure Layer
Management Plane
Spine and Leaf
Traffic Flows
Datacenter Location Types
Storage-Area Networks
iSCSI
Fibre Channel and FCoE
Network-Attached Storage
What's Next?
CHAPTER 5: Cabling Solutions and Issues
General Media Considerations
Broadband Versus Baseband Transmissions
Simplex, Half-Duplex, and Full-Duplex Modes
Data Transmission Rates
Types of Network Media
Twisted-Pair Cabling (Copper)
Coaxial Cables
Twinaxial Cables
Fiber-Optic Cables
Plenum Versus PVC Cables
Types of Media Connectors
BNC Connectors
RJ-11 Connectors
RJ-45 Connectors
F-Type Connectors and RG-59 and RG-6 Cables
Fiber Connectors
Transceivers
Media Couplers/Converters
TIA/EIA 568A and 568B Wiring Standards
Straight-Through Versus Crossover Cables
Rollover and Loopback Cables
Components of Wiring Distribution
Network Cross-Connects
Horizontal Cabling
Vertical Cables
Patch Panels
Fiber Distribution Panels
66 and 110 Blocks (T568A, T568B)
MDF and IDF Wiring Closets
Ethernet Copper and Fiber Standards
10BASE-T
100BASE-TX
1000BASE-T
10GBASE-T
40GBASE-T
1000BASE-LX and 1000BASE-SX
10GBASE-LR and 10GBASE-SR
Multiplexing Options
Troubleshooting Common Cable Connectivity Issues
Limitations, Considerations, and Issues
Throughput, Speed, and Distance
Cabling Specifications/Limitations
Cabling Considerations
Cabling Applications
Attenuation and dB Loss
Interference
Incorrect Pinout
Bad Ports
Open/Short
LED Status Indicators
Incorrect Transceivers
Duplexing Issues
TX/RX Reversed
Dirty Optical Cables
Common Tools
Cable Crimpers, Strippers, and Snips/Cutters
Punchdown Tools
Tone Generator
Loopback Adapter
OTDR
Multimeter
Cable Tester
Wire Map
Tap
Fusion Splicer
Spectrum Analyzer
Fiber Light Meter
What's Next?
CHAPTER 6: Wireless Solutions and Issues
Understanding Wireless Basics
Wireless Channels and Frequencies
Cellular Technology Access
Speed, Distance, and Bandwidth
Channel Bonding
MIMO/MU-MIMO/Directional/Omnidirectional
Antenna Ratings
Antenna Coverage
Establishing Communications Between Wireless Devices
Configuring the Wireless Connection
Troubleshooting Wireless Issues
Site Surveys
Factors Affecting Wireless Signals
Interference
Reflection, Refraction, and Absorption
Troubleshooting AP Coverage
What's Next?
CHAPTER 7: Cloud Computing Concepts and Options
Cloud Concepts
Service Models
Software as a Service
Platform as a Service
Infrastructure as a Service
Desktop as a Service
Deployment Models
Private Cloud
Public Cloud
Hybrid and Community Clouds
Infrastructure as Code
Connectivity Options
Multitenancy
Elasticity
Scalability
Security Implications
The Relationship Between Resources
What's Next?
CHAPTER 8: Network Operations
Organizational Documents and Policies
Wiring and Port Locations
Troubleshooting Using Wiring Schematics
Physical and Logical Network Diagrams
Baseline Configurations
Policies, Procedures, Configurations, and Regulations
Policies
Password-Related Policies
Procedures
Change Management Documentation
Configuration Documentation
Regulations
Labeling
High Availability and Disaster Recovery
Backups
Full Backups
Differential Backups
Incremental Backups
Snapshots
Backup Best Practices
Using Uninterruptible Power Supplies
Why Use a UPS?
Power Threats
Beyond the UPS
Cold, Warm, Hot, and Cloud Sites
High Availability and Recovery Concepts
Active-Active Versus Active-Passive
Monitoring Network Performance
Common Performance Metrics
SNMP Monitors
Management Information Base (MIB)
Network Performance, Load, and Stress Testing
Performance Tests
Load Tests and Send/Receive Traffic
Stress Tests
Performance Metrics
Network Device Logs
Security Logs
Application Log
System Logs
History Logs
Log Management
Patch Management
Environmental Factors
What's Next?
CHAPTER 9: Network Security
Common Security Concepts
Access Control
Mandatory Access Control
Discretionary Access Control
Rule-Based Access Control
Role-Based Access Control
Defense in Depth
Network Segmentation
Screened Subnet
Separation of Duties
Honeypots
RADIUS and TACACS+
Kerberos Authentication
Local Authentication
Lightweight Directory Access Protocol
Using Certificates
Auditing and Logging
Multifactor Authentication Factors
Additional Access Control Methods
802.1X
Extensible Authentication Protocol (EAP)
Network Access Control (NAC)
MAC Filtering
Risk Management
Penetration Testing
Security Information and Event Management
Common Networking Attacks
Denial-of-Service and Distributed Denial-of-Service Attacks
Types of DoS Attacks
Other Common Attacks
Social Engineering
Logic Bomb
Rogue DHCP
Rogue Access Points and Evil Twins
Advertising Wireless Weaknesses
Phishing
Ransomware
DNS Poisoning
ARP Cache Poisoning
Spoofing
Deauthentication
Brute Force
On-Path Attack
VLAN Hopping
ARP Spoofing
Vulnerabilities and Prevention
Network Hardening and Physical Security
Disposing of Assets
Implementing Physical Security
Lock and Key
Swipe Card and PIN Access
Biometrics
Two-Factor and Multifactor Authentication
Secured Versus Unsecured Protocols
Hardening Best Practices
Wireless Security
MAC Filtering
Antenna Placement and Power Levels
Isolation
Preshared Keys
Geofencing
Captive Portal
IoT Access Considerations
Remote-Access Methods
Remote File Access
VPNs
Components of the VPN Connection
VPN Connection Types
VPN Pros and Cons
IPSec
SSL/TLS/DTLS
Site-to-Site and Client-to-Site
Virtual Desktops
HTTPS/Management URL
Authentication and Authorization Considerations
Out-of-Band Management
What's Next?
CHAPTER 10: Network Troubleshooting
Troubleshooting Steps and Procedures
Identify the Problem
Identify Symptoms
Determine Whether Anything Has Changed
Duplicate the Problem if Possible
Approach Multiple Problems Individually
Establish a Theory of Probable Cause
Test the Theory to Determine the Cause
Establish a Plan of Action
Implement the Solution or Escalate
Determine Whether Escalation Is Necessary
Verify Full System Functionality
Document Findings, Actions, Outcomes, and Lessons
Software Troubleshooting Tools
Wi-Fi Analyzer
Protocol Analyzer
Bandwidth Speed Tester
Port Scanner
iperf
NetFlow Analyzer
TFTP Server
Terminal Emulator
IP Scanner
Command-Line Tools
The Trace Route Utility (tracert/traceroute)
ping
The Destination Host Unreachable Message
The Request Timed Out Message
The Unknown Host Message
The Expired TTL Message
Troubleshooting with ping
hostname
ARP
arp ping
The netstat Command
netstat -e
netstat -a
netstat -r
netstat -s
telnet
ipconfig
ifconfig
nslookup
dig
The tcpdump Command
The route Utility
nmap
Basic Network Platform Commands
Troubleshooting General Networking Issues
Common Considerations
Common Problems to Be Aware Of
Collisions
Broadcast Storm
Multicast Flooding
Asymmetrical Routing
Switching Loops
Routing Loops
Missing Route
Low Optical Link Budget
Incorrect VLAN
DNS Issues
Incorrect Gateway
Incorrect Subnet Mask
Duplicate or Incorrect IP Address
Duplicate MAC Addresses
Expired IP Address
Rogue DHCP Server
Certificate Issues
NTP Issues/Incorrect Time
DHCP Scope Exhaustion
Blocked Ports, Services, or Addresses
Incorrect Firewall Settings
Incorrect ACL Settings
Unresponsive Service
BYOD Challenges
Licensed Feature Issues
Hardware Failure
Network Performance Issues
What's Next?
Glossary
