IPv4 Addresses and Cisco Configuration

These flashcards cover key concepts related to IPv4 addresses and Cisco device configuration.

Class A IP Range

0.0.0.0 to 127.255.255.255, usable range is 1.0.0.0 to 126.255.255.255, allows for 16,777,214 hosts.

Class B IP Range

128.0.0.0 to 191.255.255.255, allows for 65,534 hosts.

Class C IP Range

192.0.0.0 to 223.255.255.255, allows for 254 hosts.

Network Address

The first address in a subnet, represents the network itself, where all host bits are 0.

Broadcast Address

The last address in a subnet, used to communicate with all hosts in the network, where all host bits are 1.

Usable Addresses

Total addresses in a subnet minus network and broadcast addresses.

Subnet Mask

Defines the network and host portions of an IP address, expressed in dotted decimal or prefix notation (e.g., /24).

Maximum Number of Hosts Formula

Calculated as 2^N - 2, where N is the number of host bits.

First Usable Address Calculation

Add 1 to the network address.

Last Usable Address Calculation

Subtract 1 from the broadcast address.

CLI Command to Check Interface Status

'show ip interface brief', displays IP address and status of interfaces.

Command to Enter Interface Configuration Mode

'interface [interface name]', e.g., 'interface G0/0'.

Enabling an Interface Command

'no shutdown', used to activate a deactivated interface.

Description Command for Interfaces

'description [text]', used to label the purpose of an interface.

Layer 1 Status

Indicates if the interface is up and physically connected.

Layer 2 Status

Indicates if Layer 2 protocol is functioning properly on the interface.