Network Services

Question 1

What is the name of the DHCP message that a client sends when it needs to
obtain IP address information? This message is the first step in the four-way
DHCP process.
a. DHCP OFFER
b. DHCP REQUEST
c. DHCP DISCOVER
d. DHCP ACK

Answer 1

Answer: c. The DHCP DISCOVER message is the first step in the four-way
DHCP process. A client broadcasts these messages on the local subnet in an
attempt to find a DHCP server.

Question 2

Where might you set the lease duration for a DHCP server that is servicing
many clients in the network?
a. The zone record
b. Scope options
c. The DHCP forwarder
d. The relay agent

Answer 2

Answer: b. You often use the scope options in DHCP to set things like lease
duration, as well as other pieces of IP configuration information that the client
might need.

Question 3

What type of DNS message is often used to perform reverse lookups?
a. PTR
b. SRV
c. TXT
d. MX

Answer 3

Answer: a. A pointer record in DNS points to a canonical name. This record
type is typically used to perform reverse lookups when required.

Question 4

What value in DNS dictates how long a DNS server or client might cache
DNS name resolution information?
a. Hop count
b. Increment duration
c. Backoff timer
d. TTL

Answer 4

Answer: d. The DNS TTL (time to live) dictates how long devices can cache
the results of name resolutions.

Question 5

What port and protocol are used by NTP? (Choose two.)
a. TCP
b. UDP
c. 69
d. 443
e. 123

Answer 5

Answer: b, e. NTP relies on UDP port 123 in its operation.

Question 6

Which component of NTP is a measure of how far the NTP client is from the
server?
a. Administrative distance
b. Stratum
c. MED
d. Metric

Answer 6

Answer: b. The stratum is a value used in NTP to provide an indicator of how
many hops a client is from the NTP server.