Course Content
Networking Today
0/7
Network Components
Network Representations and Topologies
Common Types of Networks
Internet Connections
Reliable Networks
Network Security Basic
Network Trends
Basic Switch and End Device Configuration
0/7
Cisco IOS Access
Cisco IOS Navigation
Cisco IOS Command Structure
Basic Cisco Device Configuration
Save Cisco IOS Configurations
Ports and Addresses
Configure IP Addressing
Protocols and Models
0/7
The Rules in Network Communications
Protocols
Protocol Suites
Standards Organizations
Reference Models
Data Encapsulation
Data Access
Physical Layer
0/6
Purpose of the Physical Layer
Physical Layer Characteristics
Copper Cabling
UTP Cabling
Fiber-Optic Cabling
Wireless Media
Data Link Layer
0/3
Purpose of the Data Link Layer
WAN and LAN topologies
Data Link Frame
Ethernet Switching
0/4
Ethernet Frames
Ethernet MAC Address
The MAC Address Table
Switch Speeds and Forwarding Methods
Network Layer
0/5
Network Layer Characteristics
IPv4 Packet
IPv6 Packet
How a Host Routes
Router Routing Tables
Number Systems
0/2
Binary Number System
Hexadecimal Number System
Address Resolution
Explain how ARP and ND enable communication on a network
0/3
MAC and IP
ARP
Neighbor Discovery
Basic Router Configuration
0/3
Configure Initial Router Settings
Configure Interfaces
Configure the Default Gateway
IPv4 Addressing
0/7
IPv4 Address Structure
IPv4 Unicast, Broadcast, and Multicast
Types of IPv4 Addresses
Network Segmentation
Subnet an IPv4 Network
VLSM
Structured Design
IPv6 Addressing
0/8
IPv4 Issues
IPv6 Address Representation
IPv6 Address Types
GUA and LLA Static Configuration
Dynamic Addressing for IPv6 GUAs
Dynamic Addressing for IPv6 LLAs
IPv6 Multicast Addresses
Subnet an IPv6 Network
ICMP
0/2
ICMP Messages
Ping and Traceroute Testing
Transport Layer
0/7
Transportation of Data
TCP Overview
UDP Overview
Port Numbers
TCP Communication Process
Reliability and Flow Control
UDP Communication
Application Layer
0/7
Application, Presentation, and Session
Peer-to-Peer
Web Protocols
Email Protocols
Dynamic Host Configuration Protocol (DHCP)
Domain Name Service
File Sharing Services
Network Security Fundamentals
0/4
Security Threats and Vulnerabilities
Network Attacks
Network Attack Mitigation
Device Security
Build a Small Network
0/7
Devices in a Small Network
Small Network Applications and Protocols
Scale to Larger Networks
Verify Connectivity
Host and IOS Commands
Troubleshooting Methodologies
Troubleshooting Scenarios
Basic Device Configuration
0/5
Configure a Switch with Initial Settings
Configure Switch Ports
Secure Remote Access
Basic Router Configuration
Verify Directly Connected Networks
CCNA: Switching, Routing, and Wireless Essentials
The second course in the CCNA curriculum focuses on switching technologies and router operations that support small-to-medium business networks and includes wireless local area networks (WLAN) and security concepts.
0/15
Switching Concepts
VLANs
Inter-VLAN Routing
STP
Etherchannel
DHCPv4
SLAAC and DHCPv6 Concepts
FHRP Concepts
LAN Security Concepts
Switch Security Configuration
WLAN Concepts
WLAN Configuration
Routing Concepts
IP Static Routing
Troubleshoot Static and Default Routes
CCNA: Enterprise Networking, Security, and Automation
The third CCNA course describes the architectures and considerations related to designing, securing, operating, and troubleshooting enterprise networks – including wide area network (WAN) technologies & quality of service (QoS) mechanisms for secure remote access, along with software-defined networking, virtualization, & automation concepts supporting network digitization.
0/14
Single-Area OSPFv2 Concepts
Single-Area OSPFv2 Configuration
Network Security Concepts
ACLs Concepts
ACLS for IPv4 Configuration
NAT for IPv4
WAN Concepts
VPN and IPsec Concepts
QoS Concepts
Network Management
Network Design
Network Troubleshooting
Network Virtualization
Network Automation
CCNA Course
About Lesson

Types of IPv4 Addresses

Explain public, private, and reserved IPv4 addresses.

Public and Private IPv4 Addresses

  • As defined in in RFC 1918, public IPv4 addresses are globally routed between internet service provider (ISP) routers.
  • Private addresses are common blocks of addresses used by most organizations to assign IPv4 addresses to internal hosts.
  • Private IPv4 addresses are not unique and can be used internally within any network.
  • However, private addresses are not globally routable.
Network Address and Prefix RFC 1918 Private Address Range
10.0.0.0/8 10.0.0.0 – 10.255.255.255
172.16.0.0/12 172.16.0.0 – 172.31.255.255
192.168.0.0/16 192.168.0.0 – 192.168.255.255

Routing to the Internet

  • Network Address Translation (NAT) translates private IPv4 addresses to public IPv4 addresses. NAT is typically enabled on the edge router connecting to the internet. It translates the internal private address to a public global IP address.

Special Use IPv4 Addresses

  • Loopback addresses
    • 127.0.0.0 /8 (127.0.0.1 to 127.255.255.254)
    • Commonly identified as only 127.0.0.1
    • Used on a host to test if TCP/IP is operational.

  • Link-Local addresses
    • 169.254.0.0 /16 (169.254.0.1 to 169.254.255.254)
    • Commonly known as the Automatic Private IP Addressing (APIPA) addresses or self-assigned addresses.
    • Used by Windows DHCP clients to self-configure when no DHCP servers are available.

Legacy Classful Addressing

  • RFC 790 (1981) allocated IPv4 addresses in classes
    • Class A (0.0.0.0/8 to 127.0.0.0/8)
    • Class B (128.0.0.0 /16 – 191.255.0.0 /16)
    • Class C (192.0.0.0 /24 – 223.255.255.0 /24)
    • Class D (224.0.0.0 to 239.0.0.0)
    • Class E (240.0.0.0 – 255.0.0.0)

  • Classful addressing wasted many IPv4 addresses. Classful address allocation was replaced with classless addressing which ignores the rules of classes (A, B, C).

Assignment of IP Addresses

  • The Internet Assigned Numbers Authority (IANA) manages and allocates blocks of IPv4 and IPv6 addresses to five Regional Internet Registries (RIRs). The Internet Assigned Numbers Authority (IANA) manages and allocates blocks of IPv4 and IPv6 addresses to five Regional Internet Registries (RIRs).

Other related topics

Topic Title Topic Objective
IPv4 Address Structure Describe the structure of an IPv4 address including the network portion, the host portion, and the subnet mask.
IPv4 Unicast, Broadcast, and Multicast Compare the characteristics and uses of the unicast, broadcast, and multicast IPv4 addresses.
Types of IPv4 Addresses Explain public, private, and reserved IPv4 addresses.
Network Segmentation Explain how subnetting segments a network to enable better communication.
Subnet an IPv4 Network Calculate IPv4 subnets for a /24 prefix.
VLSM Variable length subnet mask is a computer networking technique to divide an IP network into subnets with different subnet masks

Other useful information

Join the conversation
Previous
Next