1. Networking for Home and Small Businesses – Chapter 5
Network Addressing
Networking for Home and Small Businesses – Chapter 5

2. Purpose of an IP Address
A logical network address that identifies a host
A host (end-user) must have a NIC card
workstations
servers
printers
router interface
Each packet will contain a source and destination IP address
Packet Tracer Activity – Section 2

3. IP addresses 32 binary digits 4 octets Dotted decimal notation
IP Version 4
most common form of IP addresses
Over 4 billion possible IP addresses

4. Binary Numbers The IP address is made up of binary numbers (1 or 0)
Humans must be able to talk computer language to send data
We do this by converting our numbering system (Base 10 to binary)
Let’s try some . . .
Convert 140 to binary
Convert 10 to binary
Convert to Base 10
Convert to Base 10
Time to play a game -- Online Activity – Section 3

5. Parts of an IP Address Hierarchial Similar to your phone number
made up of 2 parts
network
host
determined by IP class
Similar to your phone number
Area code = network
phone number = host

6. Purpose of the Subnet Mask
Helps identify network bits (all 1s) and host bits
Boolean math or “ANDING”
What happens if both source and destination IP are on the same network??

7. Types of IP Addresses Class A Range 1-127 N.H.H.H
First bit in octet will be a 0
Default subnet mask
can create over 16 million host addresses
224 – 2 = 16,777,214 to be exact
why do you subtract 2???
Used in large organizations

8. Types of IP Addresses Class B Range 128-191 N.N.H.H
First bit in octet will be a 1
Default subnet mask
can create over 65,000 host addresses
216 – 2 = 65,534 to be exact
Used in medium-sized organizations

9. Types of IP Addresses Class C Range 192 -223 N.N.N.H
First two bits in octet will be a 11
Default subnet mask
can create 254 hosts
28 – 2 = 254 to be exact
Used in small organizations

10. Types of IP Addresses Class D Class E Range 224 - 239
used for multicasting
not for commercial use
Class E
Range
reserved for experimental use

11. Private IP Addresses Helps avoid the problem of limited IP addresses
Allows hosts to communicate locally without each device needing a public IP address
Not routed on the Internet; blocked by the ISP router
Private address ranges assigned by RFC 1918
Request for comment
all classes can be used for any size network
most use Class A

12. Unicast Address Most common type of address
Intended for a specific host
Must have both destination IP and MAC in the header

13. Broadcast Address All ones in the host portion of the IP address
Class C address: (N.N.N.H)
Broadcast address:
MAC address all Fs
FF-FF-FF-FF-FF-FF

14. Multicast Address Send packet to a group of devices
Must use multicast address range
Range –
Used for remote gaming
MAC address begins with: E

15. Using Static IP Addressing
Manually configured by the network administrator
Advantages
useful for printers, servers, etc
increased control of resources (security)
Disadvantages
time consuming

16. Using Dynamic IP Addressing
Automatic assignment of IP addresses
Useful if frequent change in users (wireless hotspot)
Uses DHCP (Dynamic Host Configuration Protocol) server
IP addresses leased for a period of time
if host is removed from the network (turned off), the IP address goes back into the pool of IP address
Preferred method for large networks
reduces the burden of network support

17. Configuring DHCP
If host is configured as DHCP client, it will not have a
IP address
Subnet Mask
Default Gateway
Clients send a DHCP address
Broadcast IP and MAC
only DHCP server replies
Server responds with DHCP offer of an IP address
Host/client sends DHCP request asking server to use the IP address
Server responds with DHCP acknowledgment

18. Obtaining an IP address from DHCP server
Multifunction device (Linksys Router) provides services to clients (SOHO network)
Configuring the DHCP server
Enter router default IP address and subnet mask for internal interface
IP =
Subnet Mask =
On DHCP screen
check range
number of users
lease time (24 hours by default)

19. Purpose of a Gateway
Used by the router to provide the path through which hosts on one network can communicate with hosts on a different network
Default gateway address
IP address of the router interface
If DHCP is being used
the DHCP server will automatically send the correct IP interface to the host to use as the default gateway

20. Address Assignment ISR (Integrated Services Router) Default IP address
Class C Private Address
Configured on router interface
Internal hosts must be assigned addresses within the same network

21. Address Management Direct Connection
direct connection from PC to ISP through modem
public address assigned to the host
Connection through Integrated Router
more than one host needs access to the Internet
modem connected to ISR
Connection through Gateway Device
ISR and modem in one unit
connect directly to ISP

22. Using NAT with a Home or Small Business Network
NAT (Network Address Translation)
Translates private IP addresses into unique public address for Internet communication
Only packets destined for different network use NAT