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Network prefix length representation of network masks
Network prefix length representation of default network masks are shown in
Table 3.6. Chapter Three: Advanced Computer Networks

Table 3.6: Network prefix Length representation of network masks
Public and Private IP addressesREADING ONLY
Address class Bits for network mask Network prefix
Class A 11111111 00000000 00000000 00000000 /8
Class B 11111111 11111111 00000000 00000000 /16

Class C 11111111 11111111 11111111 00000000 /24

For instance, the class B network ID Translation (NAT) or Port Address
138.96.0.0 with a default network mask Translation (PAT).
of 255.255.0.0 would be represented in
network prefix notation as 138.96.0.0/16. Dynamic vs. Static IP addresses:
This method of representation is also (a) Dynamic IP (DHCP)
referred to as “Classless Interdomain These addresses are automatically
Routing (CIDR)” notation. assigned by a DHCP server. They can
FOR ONLINE
change over time or when the device
reconnects to the network. They are
When a local network is not connected ideal for most personal devices and
to the Internet, any IP addressing scheme general use.
can be used. For Internet connectivity,
two types of addresses are used: public (b) Static IP
and private addresses. These addresses are manually assigned

Public addresses: Assigned by and does not change. They are essential
InterNIC, these are globally unique and for servers, printers, and other devices
routed across the Internet. For example, that need a constant IP address. They are
useful for devices that require consistent
a CIDR block like 203.0.113.0/24 is access and easy network configuration.
allocated, ensuring proper routing.

Private addresses: Reserved for internal Routing and the default gateway
use, they are not routable on the Internet. When the source and destination are on
Defined in RFC 1918, they include: the same network, IP directly delivers
10.0.0.0/8 for class A ; 172.16.0.0/12 for packets via the local area network
class B ; and 192.168.0.0/16 for class C. (LAN). If the destination is on a different

These addresses are often converted to network, IP sends packets to the default
public addresses using Network Address gateway, a router on the same network.

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