ITN 261 - Mid-Term Correct Answers
2024/2025 Update
scanner identified a vulnerability that does exist
true positive
What is this?
De facto port scanner is this.
Supports multiple scan types
TCP scan types include SYN, Full connect, FIN, XMAS
UDP scans supported
Default scan is about 1000 well-known ports
Nmap
Which of these devices would not be considered part of the Internet of Things?
A. Smartphone
B. Thermostat
C. Light bulb
D. Set-top cable box
A. A smartphone is a general-purpose computing platform with a traditional user interface--screen and
keyboard, so it isn't part of the IoT.
If you wanted a lightweight protocol to send real-time data over, which of these would you use?
A. TCP
B. HTTP
C. ICMP
D. UDP
D. TCP uses a three-way handshake, which is fairly heavyweight. HTTP uses TCP and adds more on top of
it. ICMP is used for control messages. UDP has very little overhead and is commonly used for real-time
data transport. SO THE ANSWER IS UDP
What order, from bottom to top, does the TCP/IP architecture use?
A. Network Access, Network, Transport, Application
B. Link, Internet, Transport, Application
,C. Physical, Network, Session, Application
D. Data Link, Internet, Transport, Application
B. From top to bottom, the TCP/IP architecture is Link, Internet, Transport, Session, and Appplication.
Which of these services would be considered a storage as a service solution?
A. Microsoft Azure
B. iCloud
C. Google Compute
D. DropLeaf
B. While Microsoft Azure and Google Compute have storage capabilities, they aren't storage as a service
solutions. Drop leaf is a typle of table. Dropbox is a storage as a service solution. The only one listed here
that is storage as a solution is iCloud, whick is Apple's cloud storage platform.
The UDP headers contain which of the following fields?
A. Source address, destination address, checksum, length
B. Destination port, source port, checksum, length
C. Flags, source port, destination port, checksum
D. Length, checksum, flags, address
B. The IP headers include addresses. UDP headers use ports. TCP headers use flags, but UDP headers do
not. The UDP headers have the source and destination port fields along with checksum and length.
What are the three steps in the TCP handshake as described by the flags set?
A. SYN, SYN/URG, RST
B. RST, SYN, ACK
C. SYN, SYN/ACK, ACK
D. SYN, SYN/ACK, ACK/URG
C. The three-way handshake is used to establish a connection. The first message has the SYN flag set and
includes the sequence number. The response from the server has the ACK flag set for the SYN message
that was sent from the client. The acknowledgment number is set. Addictionally, in the same message,
the server sends its own SYN flag and sequice number. The client then responds with an ACK message.
So, the sequence is SYN, SYN/ACK, and ACK.
Which of these protocols would be used to communicate with an IoT device?
A. ICMP
B. SMTP
C. Telnet
D. HTTP
D. HTTP is the only option that would be commmonly used to pass messages between a controlling
server and an IoT device.
, Which network topology are you most likely to run across in a large enterprise network?
A. Ring topology
B. Bus topology
C. Full mesh
D. Star-bus hybrid
D. An enterprise would use multiple switches that were all connected to one another over a bus, while
all the endpoints would connect to the switch in a star topology.
If you were to see the subnet mask 255.255.252.0, what CIDR notation (prefix) would you use to indicate
the same thing?
A. /23
B. /22
C. /21
D. /20
B. A /23 network would be 255.255.254.0. A /21 would be 255.255.248. A /20 would be 255.255.240.0.
Only a /22 would give you a 255.255.252.0 subnet mask.
Which of these addresses would be considered a private address (RFC 1918 address)?
A. 172.128.10.5
B. 9.10.10.7
C. 172.20.128.240
D. 250.28.17.10
C. The RFC 1918 address blocks are 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16. The only address
listed that fits into one of those address blocks is 172.20.128.240. The Address block is 172.16.0.0-
172.31.255.255.
If you were looking for the definitive documentation on a protocol, what would you consult?
A. Request for Comments
B. Manual pages
C. Standards
D. IEEE
A. The best place to find definitive documentation about protocols seen on the Internet is in the Request
for Comments (RFC) documents.
The PDU for TCP is called a _______________ .
A. Packet
B. Datagram
C. Frame
D. Segment
D. TCP uses segment for the PDU.