This document provides an overview of IP addressing concepts including assigning IP addresses, creating subnets, IPv4 and IPv6 addressing, and TCP/IP protocols. Key topics covered include the classes of IP addresses, dotted decimal notation, subnetting, public and private IP addresses, protocols like ICMP, ARP, RARP, DHCP, Telnet, and FTP.

1. Unit05:
IP Addressing

2. Overview
• IP
• Assigning IP Addresses
• Creating a Subnet
• IPv6

3. IP Addresses
IP Address
192.168.1.180
IP Address
192.168.1.180
IP Address
192.168.2.182
IP Address
192.168.2.182
IP Address
192.168.2.180
IP Address
192.168.2.180
IP Address
192.168.2.181
IP Address
192.168.2.181
IP Address
192.168.1.182
IP Address
192.168.1.182
IP Address
192.168.1.181
IP Address
192.168.1.181

4. IPv4
• Each IP address is composed of two portions
– one that identifies the network
– the other that identifies the host
• Class A addresses have a first octet value between 1
and 126.
• Class B addresses have a first octet value between 128
and 191. The addresses beginning with 127 are
reserved for loopback testing. You can test this by
pinging 127.0.0.1 on any computer.
• Class C addresses have a first octet value between 192
and 223

5. Classes of IP Addresses
Class C
Network ID Host ID
1 1 0
xw y z
Class B
Network ID Host ID
1 0
xw y z
Class A
Network ID Host ID
0
xw y z

6. Dotted Decimal Notation
11 11 11 11 11 11 11 11
8 Bits
255 Decimal Value
128128 6464 3232 1616 88 44 22 11

7. Subnet
Subnet 1
131.107.10.0
Main network
131.107.12.0
Subnet 2
131.107.3.0
131.107.10.12131.107.10.12
131.107.12.31131.107.12.31
131.107.3.27131.107.3.27
131.107.12.7131.107.12.7

8. Using CIDR
220.78.175.0
220.78.168.0
Subnet mask Subnet mask (binary)Network ID
11011100 01001110
10101000 00000000
Starting network ID
11011100 01001110
10101111 00000000
Ending network ID
Class C
Example
Class C
Example
255.255.248.0
Subnet mask Subnet mask (binary)Network ID
11111111 11111110
11111000 00000000
220.78.168.0
CIDR EntryCIDR Entry

9. Guidelines for IP Addressing
When assigning network and host IDsWhen assigning network and host IDs
Do not use 127 for a network IDDo not use 127 for a network ID
Do not use all 1’s for network and host IDDo not use all 1’s for network and host ID
Do not use all 0’s for the network IDDo not use all 0’s for the network ID
Use a host ID that is unique to the local network IDUse a host ID that is unique to the local network ID

10. IPv6
• Internet Protocol version 6 (IPv6) was designed by the
Internet Engineering Task Force (IETF) to overcome the
limitations of IPv4 addresses
• An IPv6 address is 128 bits in length
• Example : 402A:0:2F7C:1:8BB:FFE3:728D:95A

11. IPv6
• Unicast
– addresses identify a single interface and are used when a single host
sends a message to another single host.
• Multicast
– addresses identify multiple interfaces when a single host is sending
messages to many hosts.
• Anycast
– addresses identify a single interface among many interfaces and are
used when a single host sends a message to the nearest interface
available.
• Site-local
– addresses are available to any private network to use internally without
the need to register the address. They are used for networks that aren’t
connected to the Internet, or for networks that aren’t directly reachable
because of a firewall.
• The loopback
– address is 0:0:0:0:0:0:0:1 (also written as ::1). Loopback addresses
identify a logical loopback interface, which allows the node to send
packets to itself for testing purposes

12. Default Gateways
• Default gateway is an IP address of a router that is designated for
any traffic for which the route is unknown
• When a network router receives data, and it has an address for a
default gateway, it follows this process:
– The router looks at the IP header to determine the destination
IP address.
– The router determines whether the destination IP address is
on the same network segment the data was received from.
– If the destination IP address is for a different network, the
router looks in its routing table for a route to that address.
– If the router does not have a route listed for that destination
network, it selects the default gateway address.

13. Public and Private IP
Public addressesPublic addresses
Private addressesPrivate addresses
Do not have to be registered
Can be assigned by the network administrator
Are used on computers that are not accessed by the
Internet 10.x.y.z 172.16-32.x.y 192.168.x.y
Do not have to be registered
Can be assigned by the network administrator
Are used on computers that are not accessed by the
Internet 10.x.y.z 172.16-32.x.y 192.168.x.y
Are assigned by an ISP
Consist of unique class-based blocks
Are kept to a limited number
Are assigned by an ISP
Consist of unique class-based blocks
Are kept to a limited number

14. TCP/IP Protocol Functions
• ICMP
• FTP
• ARP
• DHCP
• RARP
• DHCP

15. ICMP
• Internet Control Message Protocol
(ICMP)
• An Internet layer protocol that reports on the
success or failure of data delivery
• ICMP announcements provide critical
information for troubleshooting network
problems

16. ARP
• Address Resolution Protocol (ARP)
• An Internet layer protocol that obtains the
MAC (physical) address of a host, or
node, then creates a database that maps
the MAC address to the host’s IP (logical)
address

17. RARP
• Reverse Address Resolution Protocol
(RARP)
• Allow the client to send a broadcast
message with its MAC address and
receive an IP address in reply
• RARP was originally developed as a
means for diskless workstations

18. DHCP
• Dynamic Host Configuration Protocol (DHCP)
•An automated means of assigning a
unique IP address to every device on a
network
•DHCP does not require a table of IP and
MAC addresses on the server
•DHCP does require configuration of DHCP
service on a DHCP server

19. TELNET
• A terminal emulation protocol used to log on to
remote hosts using the TCP/IP protocol suite
• Using Telnet, a TCP connection is established
and keystrokes on the user’s machine act like
keystrokes on the remotely connected machine
• Telnet is notoriously insecure

20. FTP
•Used to send and receive files via TCP/IP
•FTP commands will work from your operating
system’s command prompt
•Many FTP hosts accept anonymous logins