Cisco 1-3 Review

What is the primary function of an intermediary device in a network?

To connect end devices and direct data across the network.

What does QoS stand for in networking?

Quality of Service

What is the main purpose of Quality of Service (QoS)?

To manage data traffic and prioritize critical communications to reduce packet loss, delay, and jitter.

What are two common security measures used to protect end devices?

Implementing firewalls and installing antivirus software.

What is network security?

The protection of network infrastructure, data, and services from unauthorized access or threats.

What is Cisco IOS?

The Internetwork Operating System used on most Cisco routers and switches.

What are the primary command modes in the Cisco IOS CLI?

User EXEC mode, Privileged EXEC mode, and Global Configuration mode.

Which command is used to enter Privileged EXEC mode from User EXEC mode?

enable

Which command is used to enter Global Configuration mode?

configure terminal

How can an administrator break out of initial configuration dialogs or abort a command?

By using key combinations like Ctrl+C or Ctrl+Shift+6.

What command is used to encrypt all plain-text passwords in Cisco IOS?

service password-encryption

Where are active router and switch configurations stored while the device is powered on?

In RAM as the running-config.

Where are permanent Cisco device configuration files saved to survive reboots?

In NVRAM as the startup-config.

Which command saves the current running configuration to NVRAM?

copy running-config startup-config

What is the default VLAN assigned to all switch ports on a Cisco switch out of the box?

VLAN 1

Which command displays a quick status summary of all switch interfaces and their IP addresses?

show ip interface brief

What is the purpose of configuring 'line vty 0 4' on a Cisco device?

To configure virtual terminal lines for remote management access via Telnet or SSH.

What are three common application layer protocols included in the TCP/IP protocol suite?

HTTP, DNS, and DHCP.

What is the popular mnemonic phrase used to remember the OSI model layers?

All People Seem To Need Data Processing

In the OSI model mnemonic 'All People Seem To Need Data Processing', what does 'All' represent?

Application layer

In the OSI model mnemonic, what does 'People' represent?

Presentation layer

In the OSI model mnemonic, what does 'Seem' represent?

Session layer

In the OSI model mnemonic, what does 'To' represent?

Transport layer

In the OSI model mnemonic, what does 'Need' represent?

Network layer

In the OSI model mnemonic, what does 'Data' represent?

Data Link layer

In the OSI model mnemonic, what does 'Processing' represent?

Physical layer

What is the primary responsibility of the Transport layer in network models?

Logical communication between application processes running on different hosts, ensuring reliable or unreliable delivery.

What is the prompt symbol for User EXEC mode in Cisco IOS?

The greater-than sign (>)

What is the prompt symbol for Privileged EXEC mode in Cisco IOS?

The pound sign (#)

Which command is used to return from Global Configuration mode back to Privileged EXEC mode?

exit

What command allows an administrator to assign a hostname to a Cisco switch?

hostname [name]

What command sets a password for the Privileged EXEC mode?

enable secret [password]

What command configures a message of the day (MOTD) banner on a Cisco device?

banner motd #[message]#

Which command displays the current running configuration file?

show running-config

Which command displays the startup configuration file stored in NVRAM?

show startup-config

What type of memory loses its contents when the Cisco device is powered off?

RAM (Random Access Memory)

What type of memory retains its contents even when power is turned off?

NVRAM (Non-Volatile RAM)

What is the function of flash memory in a Cisco router or switch?

To store the Cisco IOS image file permanently.

What does VLAN stand for in networking?

Virtual Local Area Network

Why are VLANs used in modern switched networks?

To segment networks logically for improved security and performance.

What command is used to create a new VLAN and enter its configuration mode?

vlan [vlan-id]

Which command assigns an IP address to a switch management interface like VLAN 1?

ip address [ip-address] [subnet-mask]

Which command must be entered on an interface to activate it after assigning an IP address?

no shutdown

What does DHCP stand for?

Dynamic Host Configuration Protocol

What is the main function of DHCP?

To automatically assign IP addresses and network configuration parameters to devices.

What does DNS stand for in networking protocols?

Domain Name System

What is the primary role of DNS?

To resolve human-readable domain names into numerical IP addresses.

What is the function of the Network layer in the OSI model?

Path determination and packet forwarding (routing) across different networks.

What is the function of the Data Link layer in the OSI model?

Physical addressing (MAC addresses) and error detection across a local link.

What is the function of the Physical layer in the OSI model?

Transmission of raw binary bits over a physical medium (cables, wireless).

What is the main security difference between SSH and Telnet?

SSH encrypts remote management traffic, whereas Telnet transmits data in clear text.

Which command is used to test end-to-end network connectivity?

ping

What command is used to trace the path a packet takes to a destination?

traceroute

What is the primary purpose of a default gateway?

To connect a local network to remote networks and route external traffic.

How many bits make up a standard MAC address?

48 bits

What protocol is used to securely manage Cisco network devices remotely?

SSH (Secure Shell)