1. IP Adressing in IPv4 By
Kenneth Lundby

2. IPv4 Addresses Basics about IP addressing Ipv4 classes and structures
NAT
Domain names and IP

3. Basics about IP addressing
Operates in the Network Layer of the OSI model
IPv4 was the first iteration of the protocol to be widely deployed
32 bit addresses
Over 4 billion different addresses

4. IPv4 classes and stucture
32 bit addresses
Divided into 4 octets
Divided into classes
Defines what is the Network-ID and what is the Host-ID
Originally the first octet was the Network ID and the last 3 was the Host ID

5. IPv4 classes and structure
Now we have class A, B & C Networks
Class A: where 112/the first octet is the Network ID, the rest is the Host ID
Class B: The 2 first octets are the Network ID
Class C: The first 3 octets make up the Network ID
In a class A network you can only have 256 networks, while in a Class C network you can have 2 million networks, you can only have 254 hosts on each

6. NAT Network Address Translation
Translation from public to private IP addresses
Resolve issues with to few IP addresses
Private IP addresses:
Class A
Class B
Class C
– Class C

7. NAT You usually only have 1 single public IP address
This would then typically be your Gateway
The gateway handles all traffic in and out
It translates and sends the packets to the right destination

8. Domain names and IP IP addresses are hard for humans to remember
Domain Name Server
Nslookup =
Is like a phone book
Name Servers are distributed over the Internet

9. The End Questions? Resources: