2.6 - Compare & contrast common network configuration concepts Flashcards
What does DNS translate?
2.6 Compare & contrast common network configuration concepts: DNS - Address
FQDNs (aka URLs)
Fully Qualified Domain Name
What are address records aka?
2.6 Compare & contrast common network configuration concepts: DNS - Address
A & AAAA records
(quad A)
What do address records do in DNS?
(A & AAAA)
2.6 Compare & contrast common network configuration concepts: DNS - Address
Link FQDNs with their IP addresses
(Fully Qualified Domain Names)
FQDN like www.dprocomputer.com
What addresses do A records correspond to?
2.6 Compare & contrast common network configuration concepts: DNS - Address
IPv4 addresses
What addresses do AAAA records correspond to?
2.6 Compare & contrast common network configuration concepts: DNS - Address
IPv6 addresses
What do MX records in DNS do?
2.6 Compare & contrast common network configuration concepts: DNS - MX
Gives email servers the destination email server’s FQDN
It essentially directs emails to an email server
What do MX records in DNS require for email destination setup?
2.6 Compare & contrast common network configuration concepts: DNS - MX
Email server with an active address record
What do Pointer (PTR) records in DNS do?
2.6 Compare & contrast common network configuration concepts: DNS
Does reverse lookup (IP to name)
What records are used for forward lookup? & reverse lookup?
For IP/domains
2.6 Compare & contrast common network configuration concepts: DNS
Address & PTR records
Address for forward, PTR for reverse
Meaning of MX record?
2.6 Compare & contrast common network configuration concepts: DNS - MX
Mail Exchanger record
Meaning of TXT record?
2.6 Compare & contrast common network configuration concepts: DNS - TXT
Text record
What are TXT records used for?
2.6 Compare & contrast common network configuration concepts: DNS - TXT
Email security & verification
3 types of TXT records used for spam management?
2.6 Compare & contrast common network configuration concepts: DNS - TXT
- DMARC
- DKIM
- SPF
They’re typically used together
Meaning of DMARC?
2.6 Compare & contrast common network configuration concepts: DNS - TXT
Domain-based Message Authentication, Reporting, & Conformance
Meaning of DKIM?
2.6 Compare & contrast common network configuration concepts: DNS - TXT
DomainKeys Identified Mail
Meaning of SPF?
2.6 Compare & contrast common network configuration concepts: DNS - TXT
Sender Policy Framework
What do SPF records in DNS do?
2.6 Compare & contrast common network configuration concepts: DNS - TXT: SPF
Specifies which email servers are allowed to send emails on behalf of a domain
- If you set up an SPF record for “yourcompany.com” to authorize Gmail’s servers, only emails sent through Gmail’s servers will be approved.
- If an impersonator uses a Microsoft server to send emails claiming to be from “yourcompany.com,” they won’t be approved by your SPF record because it only accepts emails from Gmail’s servers.
What do SPF records prevent?
2.6 Compare & contrast common network configuration concepts: DNS - TXT: SPF
domain name spoofing & unauthorized email sending
What does DKIM in DNS do?
2.6 Compare & contrast common network configuration concepts: DNS - TXT: DKIM
Verifies the authenticity & domain of origin of an email
By using digital signatures
It verifies the email message actually came from the claimed domain & has not been modified during transit
How does DKIM enhance email security?
2.6 Compare & contrast common network configuration concepts: DNS - TXT: DKIM
Ensures emails have not been modified/tampered durng transit
The signature is changed if the email is modified at any point
What does DMARC do?
2.6 Compare & contrast common network configuration concepts: DNS - TXT: DMARC
Specifies actions for unvalidated messages
When are DHCP leases renewed?
2.6 Compare & contrast common network configuration concepts: DHCP - Leases
When device rejoins the network
How do devices maintain the same temporary IP address assigned via DHCP?
2.6 Compare & contrast common network configuration concepts: DHCP - Leases
By periodically checking in with DHCP server
What happens if a device fails to check in with DHCP?
2.6 Compare & contrast common network configuration concepts: DHCP - Leases
Lease expirese & the IP address returns to IP address pool
