Chapter 8
Intro to Routing & Switching

Upon completion of this chapter, you should be able
to:
 Describe the structure of an IPv4 address.
 Describe the purpose of the subnet mask.
 Compare the characteristics and uses of the unicast,
broadcast and multicast IPv4 addresses.
 Compare the use of public and private addresses.
 Explain the need for IPv6 addressing.
 Describe the representation of an IPv6 address.
 Describe types of IPv6 network addresses.
 Configure global unicast addresses.
 Describe multicast addresses.
 Describe the role of ICMP in an IP network.
 Use ping & traceroute to test network connectivity.
8.1
 Each
host needs IP to communicate
 Logical address
 Assigned to the NIC

Computers, network printer, router interfaces
 Remember

Packet has source & destination IP
 What
protocol translates the name to the IP
address?

DNS
 What

53
port does it use?
 Logical
(not physical like MAC)
 IPv4 has 32 bits, 4 octets


8 bits in each octet
11111111.10101010.11001100.00100101
 Convert

192.101.28.36
 Value

that to decimal:
in each octet from 0-255
That’s a total of 256 numbers.
 Add

up the values of the binary 1’s
128
64
32
16
8
4
2
1
1
0
0
1
1
1
0
0
156
 11100101

229
 8.1.1.4

Add up the bit values to come up with the
decimal answer
 8.1.1.7

Decimal to Binary Conversions
Convert the decimal number to bits
 8.1.1.8

Binary to Decimal Conversions
Binary Game
Create an account on cisco.com
 How

32
 How

many bits in an IPv4 address?
many octets? How many bits in each?
4 octets; 8 bits in each
 What
can be the decimal value range of each
octet?

0-255
 How

256
many numbers is 0-255?
8.2
 Network


Identifies network to the router
Router cares about this part
 Host


portion
portion
Identifies the specific host
Router doesn’t care about this part

Hierarchical Addressing
 192.175.36.9
 Subnet




Mask
Helps router decide which network packet is on
Helps show which part of IP is network & host
32 bits
192.168.6.5 255.255.255.0
 Binary
1’s - ID the network portion
 Binary 0’s - ID the host portion
 199.81.210.17
 255.255.255.240
 What
network does this belong to?
 What

is the purpose of the subnet mask?
To help the router identify the destination
network
A
packet enters a router. Which address does
it look at?

Destination IP
 What
process does it do with the destination
IP & the subnet mask?

ANDs it
 What

is the result of the ANDing?
The destination network
 SM
helps tells us how many hosts are on that
network




255.255.255.00000000
Binary 0= identifies # of hosts on that network
8 ZEROS is 28=256
Subtract 2 for useable number


Unusable:
 00000000 (.0) is the network ID
 11111111 (.255) is the broadcast address for a
network
Total Useable is 254
 SM


128= 10000000
27= 128-2 is 126 hosts
 SM



255.255.255.224
224= 11100000
25= 32-2 is 30 hosts
 SM

255.255.255.128
255.255.240.0
.240.0= 11110000.00000000
212= 4096-2 is 4094 hosts
 One



PC is 192.168.18.107 255.255.255.0
What is network does it belong to?
How many useable hosts?
Give PC’s addresses.
8.1.4
 Class
A
Large organizations
 1-126
 Default SM= 255.0.0.0



How many hosts available?





One octet for network, 3 octets for hosts
224= over 16 million
10.52.33.7
N.H.H.H
255.0.0.0
120.111.99.87
 15.7.92.5
255.0.0.0
 15=
Class A
 Default SM for Class A= 255.0.0.0
 Network portion of address= 15.
 Host portion= .7.92.5
 Network ID= 15.0.0.0

All zero’s in the host portion
 Broadcast

address= 15.255.255.255
All binary one’s in the host portion
 Class
B
Medium organizations
 128-191
 Default SM= 255.255.0.0



How many hosts available?





Two octets for network, 2 octets for hosts
216= over 65,000
130.52.33.7
N.N.H.H
255.255.0.0
185.111.99.87
 167.101.52.36
255.255.0.0
 167=
Class B
 Default SM for Class B= 255.255.0.0
 Network portion of address= 167.101
 Host portion= .52.36
 Network ID= 167.101.0.0

All zero’s in the host portion
 Broadcast

address= 167.101.255.255
All binary one’s in the host portion
 Class
C
Small organizations
 192-223
 Default SM= 255.255.255.0



How many hosts available?





Three octets for network, 1 octet for hosts
28= 256-2 (254 useable)
199.52.33.7
N.N.N.H
255.255.255.0
220.111.99.87
 210.44.200.89
255.255.255.0
 210=
Class C
 Default SM for Class C= 255.255.255.0
 Network portion of address= 210.44.200
 Host portion= .89
 Network ID= 210.44.200.0

All zero’s in the host portion
 Broadcast

address= 210.44.200.255
All binary one’s in the host portion
 Class


D is multicast (one to a group)
224.0.0.0- 239.255.255.255
 Class


D not for hosts
E not for hosts
For testing only
240-255
 All
0’s in host portion(s) = network ID
 All 1’s in host portion(s)= broadcast
CAN NOT USE THESE ADDRESSES FOR HOSTS!
 Address
 What
168.19.203.12 255.255.0.0
class?
 What are the network portions?
 What are the host portions?
 What is the network address/ID?
 What is the broadcast address?
 What is the first usable address?
 8.1.2.8
Lab
 8.1.2.9
ANDing Activity

Determine the network address
 Lots
of Practice!
Which version IP addresses are we dealing
with?
IPv4
How many bits in an IP address?
32
How many octets in an IP address?
4
Which part of this address is the host portion?
199.81.71.6
6
Which network does this belong on? 201.14.6.5
255.255.255.0
201.14.6.0 network
How many total hosts can be on that network?
Useable?
256
254, why?
8.1.4
 Some
addresses are reserved & can not be routed
across Internet
 You can have a public IP for network/servers &
private for hosts inside

Saves IP addresses
Address
Class
Address Range
A
B
C
10.0.0.0- 10.255.255.255
172.16.0.0- 172.31.255.255
192.168.0.0- 192.168.255.255
 If
host does not connect DIRECTLY to
Internet, it can have a private IP
 Router
BLOCKS private IP’s
 Great Security!!!
 Private IP’s can not
 127.0.0.0
testing
 169
be seen from Internet
range is reserved for loopback
is APIPA (local link)- no IP received from
DHCP server
 8.1.4.2

Decide to pass or block the IP depending upon if
it’s private or public
 8.1.4.7

Pass or Block IP Addresses
Public or Private
Drag each IP to public or private
 Handout

Host, Network#, or Broadcast address, Class,
default SM, usable/unusable for hosts
 What

10
 What

is unique about the private addresses?
They are not routable
 What

is the private range for C?
192.168
 What

is the private range for B?
172.16- 172.31
 What

is the private range for class A?
does it mean if your address is 169?
APIPA; you did not get an IP from DHCP server
8.1.3
 One-to-one
or Source to destination
 One-to-all
(source to all) in segment
 All hosts will look at it
 All 1’s in host portion(s) of address
 Broadcast IP & MAC (all F’s)
 Default Broadcasts



A- 10.255.255.255 255.0.0.0
B- 172.16.255.255 255.255.0.0
C- 192.168.1.255 255.255.255.0
 One-to-group
 Class
D 224.0.0.0- 239.255.255.255
 Multicast MAC begins with 01-00-5E
 Where


is it used?
Gaming
Distance learning
 Unicast,
Multicast, or Broadcast
 8.1.3.6


Unicast, Broadcast, Multicast
Look at the destination IP & click the devices
that will receive it
Try it several time
 Handout
 DOS



Netstat –e
Do this every 10 seconds
Pay attention to non-unicast packets
160.50.23.6 255.255.0.0; What network is this on?
160.50.0.0
Which default SM has the most hosts?
Class A 255.0.0.0
Over 16 million!
How many useable hosts in a Class C?
254
220.101.5.90 255.255.255.0; What network is this
on?
220.101.5.0
What are the private IP addresses?
10, 172.16-172.31, 192.168.
What is the MAC broadcast frame in hex?
FF-FF-FF-FF-FF-FF
What is the MAC for a multicast?
01-00-5E
One to one communication is…
Unicast
To send a unicast message, which addresses do
you need?
Source & dest. IP & MAC
 Complete
 Take
the study guide handout
the quiz on netacad.com
 Jeopardy
review
In this chapter, you learned:
Chapter 8
Intro to Routing & Switching