Network Configuration Concepts

What is the purpose of an A record?

Maps a hostname to an IPv4 address

What is the purpose of an AAAA record?

Maps a hostname to an IPv6 address

What is the purpose of a CNAME record?

Creates an alias for another hostname

What is the purpose of an MX record?

Identifies mail servers responsible for receiving email

What is the purpose of a TXT record?

Stores text-based information for a domain

What is the purpose of a PTR record?

Maps an IP address to a hostname for reverse DNS lookups

Which DNS record is used for reverse DNS lookups?

PTR

Which DNS record stores SPF information?

TXT

Which DNS record does not direct network traffic?

TXT

Which DNS record is commonly used for domain verification and security information?

TXT

Which DNS record maps a hostname to a 32-bit address?

A record

Which DNS record maps a hostname to a 128-bit address?

AAAA record

What does SPF stand for?

Sender Policy Framework

What is the purpose of SPF?

Specifies which servers are authorized to send email for a domain

What type of DNS record stores SPF information?

TXT record

What email attack does SPF help prevent?

Email spoofing

What does DKIM stand for?

DomainKeys Identified Mail

What is the purpose of DKIM?

Adds a digital signature to outgoing emails

What does DKIM verify?

Message integrity. Sender authenticity

What does DMARC stand for?

Domain-based Message Authentication Reporting and Conformance

What is the purpose of DMARC?

Tells mail servers what to do if SPF or DKIM checks fail

What DMARC policies can be configured?

None. Quarantine. Reject

What additional feature does DMARC provide?

Reports to domain owners

What is the memory trick for SPF?

Sender

What is the memory trick for DKIM?

Signature

What is the memory trick for DMARC?

Decision

What is a DHCP lease?

The temporary time a device can use an assigned IP address

What happens when a DHCP lease expires?

The device must renew its IP address

What is a DHCP reservation?

A permanent IP assignment based on a device's MAC address

Which devices commonly use DHCP reservations?

Servers. Printers. Cameras

What is a DHCP scope?

The range of IP addresses DHCP can assign

What is a DHCP exclusion?

Addresses removed from the DHCP pool so they cannot be assigned automatically

Why are DHCP exclusions used?

To protect addresses intended for static devices

Which devices commonly use excluded IP addresses?

Servers. Routers. Printers. Access points

True or False: DHCP exclusions prevent clients from receiving statically assigned addresses.

True

What is a VLAN?

A logical grouping of devices that acts as the same network

What are the benefits of VLANs?

Better security. Reduced broadcasts. Easier management

What problem do VLANs solve?

Logical network separation

What is a VPN?

An encrypted connection across a public network

What are common uses of VPNs?

Remote access. Secure public Wi-Fi connections. Access to company resources

What are the benefits of a VPN?

Encryption. Privacy. Secure remote access

What is the main purpose of a VLAN?

Logically separates networks

What is the main purpose of a VPN?

Provides a secure encrypted tunnel

What phrase helps remember A records?

Address equals IPv4

What phrase helps remember AAAA records?

AAAA equals IPv6

What phrase helps remember CNAME records?

Nickname or alias

What phrase helps remember MX records?

Mail exchange

What phrase helps remember TXT records?

Text information only

What phrase helps remember a DHCP lease?

Temporary rental

What phrase helps remember a DHCP reservation?

Permanent assignment

What phrase helps remember a DHCP scope?

Available address pool

What phrase helps remember a DHCP exclusion?

Keep DHCP away

What phrase helps remember VLAN?

Virtual broadcast domain

What phrase helps remember VPN?

Private tunnel through the Internet