Fundamentals of NetworkingDiscovery 1, Chapter 5Network Addressing
Objectives
•Describe the purpose of an IP Address and Subnet Mask and how they are used on the Internet
•Describe the types of IP Addresses available•Describe the methods of obtaining an IP Address•Describe the use of NAT on a home or small business
network using an ISR
IP Addresses
&
Subnet Masks
Purpose of an IP Address
•Each host needs IP to communicate• Logical address•Assigned to the NIC▫Computers, network printer, router interfaces
•Remember▫Packet has source & destination IP
Everything is IP
Complete Packet Tracer 5.1.1.2“Connecting to a Web Server Using IP”
IP Address Facts
• Logical (not physical like MAC)• IPv4•32 bits, 4 octets▫8 bits in each octet▫11111111.10101010.11001100.00100101
•Written in decimal▫192.101.28.36
•Value in each octet from 0-255▫That’s a total of 256 numbers.
Convert binary to decimal
•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
Binary/Decimal Conversions
•How to Do Conversions Handout
•Binary & Decimal Conversions Practice
•Binary Game in Curriculum 5.1.2.3
Review
Parts of an IP Address•Network portion▫ Identifies network to the router▫Router cares about this part
•Host portion▫ Identifies the specific host▫Router doesn’t care about this part
Hierarchical Addressing
•192.175.36.9
Activity
IP & Subnet Mask Interaction
•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
What network are these on?ANDing
ANDing- What network?
•199.81.210.17•255.255.255.240
•What network does this belong to?
Review
How many hosts? Unsubnetted
•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
How many total & useable hosts?•SM 255.255.255.128▫128= 10000000▫27= 128-2 is 126 hosts
•SM 255.255.255.224▫224= 11100000▫25= 32-2 is 30 hosts
•SM 255.255.240.0▫.240.0= 11110000.00000000▫212= 4096-2 is 4094 hosts
Figure It Out
•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.
Binary/Dec/Hex
•Hex= MAC address•0-9, A-F (10-15)•AB
Handout & Lab
•5.1.4 Lab (No Calculator)
•Homework- Decimal/Hex/Binary Conversion
Review1. Which version IP addresses are we dealing with?
▫ IPv42. How many bits in an IP address?
▫ 323. How many octets in an IP address?
▫ 44. Which part of this address is the host portion?
199.81.71.6▫ 6
Review
1. Which network does this belong on? 201.14.6.5 255.255.255.0▫ 201.14.6.0 network
2. How many total hosts can be on that network? Useable?▫ 256▫ 254, why?
Types of
IP Addresses
IP Classes & Default SM
•Class A▫ Large organizations▫1-127▫Default SM= 255.0.0.0
One octet for network, 3 octets for hosts▫How many hosts available?
224= over 16 million▫10.52.33.7▫N.H.H.H▫255.0.0.0▫120.111.99.87
Class A Example
•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
IP Classes & Default SM
•Class B▫Medium organizations▫128-191▫Default SM= 255.255.0.0
Two octets for network, 2 octets for hosts▫How many hosts available?
216= over 65,000▫130.52.33.7▫N.N.H.H▫255.255.0.0▫185.111.99.87
Class B Example
•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
IP Classes & Default SM
•Class C▫Small organizations▫192-223▫Default SM= 255.255.255.0
Three octets for network, 1 octet for hosts▫How many hosts available?
28= 256-2 (254 useable)▫199.52.33.7▫N.N.N.H▫255.255.255.0▫220.111.99.87
Class C Example
•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
Other IP Classes & More•Class D & E not for commercial use▫D is multicast (one to a group)▫224.0.0.0- 239.255.255.255
•All 0’s in host portion(s) = network ID•All 1’s in host portion(s)= broadcast•CAN NOT USE THOSE FOR HOSTS!
IP Cheat Sheet
Handouts
•Activity on 5.2.1.2
• Lots of Practice!
Public/Private IP’s
Address Class
Address Range
A 10.0.0.0- 10.255.255.255B 172.16.0.0- 172.31.255.255C 192.168.0.0- 192.168.255.255
•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
Private IP’s• 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 be seen from Internet
•127.0.0.0 range is reserved for loopback testing
Private Nets- 5.2.2.3 Activity
Review
Unicast Address Communication•One-to-one or Source to destination
Broadcast Address Communication•One-to-all or 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
Broadcast Address Communication
Multicast Address Communication•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
Multicast Communication
Which one, based on the MAC?
•Unicast, Multicast, or Broadcast
Activity & Handout
•5.2.3.4•Handout•DOS▫Netstat –e▫Do this every 10 seconds▫Pay attention to non-unicast packets
Review1. 160.50.23.6 255.255.0.0; What network is this on?
▫ 160.50.0.02. Which default SM has the most hosts?
▫ Class A 255.0.0.0▫ Over 16 million!
3. How many useable hosts in a Class C?▫ 254
4. 220.101.5.90 255.255.255.0; What network is this on?▫ 220.101.5.0
Review1. What are the private IP addresses?
▫ 10, 172.16-172.31, 192.168.2. What is the MAC broadcast frame in hex?
▫ FF-FF-FF-FF-FF-FF3. What is the MAC for a multicast?
▫ 01-00-5E4. One to one communication is…
▫ Unicast5. To send a unicast message, which addresses do you
need?▫ Source & dest. IP & MAC
How IP
Addresses Are
Obtained
Assigning IP Addresses•Static▫Manually type in IP
Address▫Good for printers or
servers Devices people access
all the time You wouldn’t want
their address changing!
▫Good documentation!!!!
Assigning IP Addresses•Dynamic▫Assigned auto by DHCP
server▫Assigns IP, SM, DG,
more▫Good for larger
networks or with mobile/new devices
▫Leased addresses
Assigning IP Addresses
•Admins have a pool of IP addresses▫DHCP assigns from the pool
•SOHO routers usually have DHCP
•Medical field-▫Legal requirement▫Must track who is on machine▫DHCP server assigns & keeps log of users
DHCP Servers• How you get on the net in a hotel, Starbucks, or BK• Either dedicated server or mixed in another device▫ From ISP or on your ISR
How DHCP Works
Configuring DHCP on Linksys
•192.168.1.1•PacketTracer Lab5.3.3.3
Review1. Which addresses does a host use to discover a
DHCP server?▫ 255.255.255.255▫ FF-FF-FF-FF-FF-FF
2. Who sees that? Who responds?▫ All on the segment▫ The DHCP server
3. What happens to a PC’s IP when you shut down?▫ Goes back to the DHCP pool of addresses
Address
Management
Network Boundaries
The Network In & Out
How to Connect to the ISP
•Directly▫1 PC to a modem▫PC gets address from ISP
• ISR▫Modem to ISR▫Internal PC’s get addresses from ISR
•Gateway Device▫ISR & Modem in one▫Internal gets private IP’s
How to Connect to the ISP
NAT
•Translates private into public addresses•Prevents external from seeing internal
NAT Translation
•A private (local) source IP address is translated to a public (global) address. ▫The process is reversed for incoming packets.▫The integrated router is able to translate many internal
IP addresses to the same public address, by using NAT.
NAT Example
Packet Tracer
•5.4.3.2
Review
1. Which address does the PC need to access the Internet?
▫ Default gateway address of the ISR2. Which devices translates NAT?
▫ ISR
Review- 11 Questions
Advanced Review- 6 Questions
Network AddressingNetworking for Home & Small Business