Domain 4 Flashcards
Communication and Network Security
Which of the following protocols is considered connection-oriented?
A. IP
B. ICMP
C. UDP
D. TCP
D. TCP is the only connection-oriented protocol listed. A connection-oriented
protocol provides reliable connectivity and data transmission, while a connectionless
protocol provides unreliable connections and does not promise or ensure data
transmission.
Which of the following shows the layer sequence as layers 2, 5, 7, 4, and 3?
A. Data link, session, application, transport, and network
B. Data link, transport, application, session, and network
C. Network, session, application, network, and transport
D. Network, transport, application, session, and presentation
A. The OSI model is made up of seven layers: application (layer 7), presentation
(layer 6), session (layer 5), transport (layer 4), network (layer 3), data link
(layer 2), and physical (layer 1).
Metro Ethernet is a MAN protocol that can work in network infrastructures
made up of access, aggregation, metro, and core layers. Which of the following
best describes these network infrastructure layers?
A. The access layer connects the customer’s equipment to a service provider’s
aggregation network. Aggregation occurs on a core network. The metro layer
is the metropolitan area network. The core connects different metro networks.
B. The access layer connects the customer’s equipment to a service provider’s core
network. Aggregation occurs on a distribution network at the core. The metro
layer is the metropolitan area network.
C. The access layer connects the customer’s equipment to a service provider’s
aggregation network. Aggregation occurs on a distribution network. The metro
layer is the metropolitan area network. The core connects different access layers.
D. The access layer connects the customer’s equipment to a service provider’s aggregation network. Aggregation occurs on a distribution network. The metro layer is the metropolitan area network. The core connects different metro networks.
D. The access layer connects the customer’s equipment to a service provider’s
aggregation network. Aggregation occurs on a distribution network. The metro
layer is the metropolitan area network. The core connects different metro
networks.
Systems that are built on the OSI model are considered open systems. What does
this mean?
A. They do not have authentication mechanisms configured by default.
B. They have interoperability issues.
C. They are built with internationally accepted protocols and standards so they
can easily communicate with other systems.
D. They are built with international protocols and standards so they can choose what types of systems they will communicate with.
C. An open system is a system that has been developed based on standardized
protocols and interfaces. Following these standards allows the systems to
interoperate more effectively with other systems that follow the same standards
Which of the following protocols work in the following layers: application, data
link, network, and transport?
A. FTP, ARP, TCP, and UDP
B. FTP, ICMP, IP, and UDP
C. TFTP, ARP, IP, and UDP
D. TFTP, RARP, IP, and ICMP
C. These listed protocols work at these associated layers: TFTP
(application), ARP (data link), IP (network), and UDP (transport).
What takes place at the data link layer?
A. End-to-end connection
B. Dialog control
C. Framing
D. Data syntax
C. The data link layer, in most cases, is the only layer that understands the
environment in which the system is working, whether it be Ethernet, Token
Ring, wireless, or a connection to a WAN link. This layer adds the necessary
headers and trailers to the frame. Other systems on the same type of network
using the same technology understand only the specific header and trailer format
used in their data link technology.
What takes place at the session layer?
A. Dialog control
B. Routing
C. Packet sequencing
D. Addressing
A. The session layer is responsible for controlling how applications communicate,
not how computers communicate. Not all applications use protocols that work
at the session layer, so this layer is not always used in networking functions. A
session layer protocol sets up the connection to the other application logically
and controls the dialog going back and forth. Session layer protocols allow
applications to keep track of the dialog.
Which best describes the IP protocol?
A. A connectionless protocol that deals with dialog establishment, maintenance,
and destruction
B. A connectionless protocol that deals with the addressing and routing of packets
C. A connection-oriented protocol that deals with the addressing and routing
of packets
D. A connection-oriented protocol that deals with sequencing, error detection,
and flow control
B. The IP protocol is connectionless and works at the network layer. It adds source
and destination addresses to a packet as it goes through its data encapsulation
process. IP can also make routing decisions based on the destination address.
Which of the following is not one of the messages exchanged during the DHCP
lease process?
i. Discover
ii. Offer
iii. Request
iv. Acknowledgment
A. All of them are exchanged
B. None of them are exchanged
C. i, ii
D. ii, iii
B. The four-step DHCP lease process is
1. DHCPDISCOVER message: This message is used to request an IP address lease from a DHCP server.
2. DHCPOFFER message: This message is a response to a DHCPDISCOVER message, and is sent by one or numerous DHCP servers.
3. DHCPREQUEST message: The client sends this message to the initial DHCP server that responded to its request.
4. DHCPACK message: This message is sent by the DHCP server to the DHCP client and is the process whereby the DHCP server assigns the IP address lease to the DHCP client.
An effective method to shield networks from unauthenticated DHCP clients is
through the use of __________ on network switches.
A. DHCP snooping
B. DHCP protection
C. DHCP shielding
D. DHCP caching
A. DHCP snooping ensures that DHCP servers can assign IP addresses to only
selected systems, identified by their MAC addresses. Also, advance network
switches now have the capability to direct clients toward legitimate DHCP servers
to get IP addresses and to restrict rogue systems from becoming DHCP servers
on the network.
Which of the following is not a characteristic of the IEEE 802.11a standard?
A. It works in the 5-GHz range.
B. It uses the OFDM spread-spectrum technology.
C. It provides 52 Mbps in bandwidth.
D. It covers a smaller distance than 802.11b.
C. The IEEE standard 802.11a uses the OFDM spread-spectrum technology,
works in the 5-GHz frequency band, and provides bandwidth of up to 54 Mbps.
The operating range is smaller because it works at a higher frequency.
Wireless LAN technologies have gone through different versions over the years
to address some of the inherent security issues within the original IEEE 802.11
standard. Which of the following provides the correct characteristics of WPA2 in
Enterprise mode?
A. IEEE 802.1X, WEP, MAC
B. IEEE 802.1X, EAP, TKIP
C. IEEE 802.1X, EAP, WEP
D. IEEE 802.1X, EAP, CCMP
D. Wi-Fi Protected Access 2 requires IEEE 802.1X or preshared keys for
access control, Extensible Authentication Protocol (EAP) or preshared keys
for authentication, and the Advanced Encryption Standard (AES) algorithm in
counter mode with CBC-MAC Protocol (CCMP) for encryption.
Which of the following is not a characteristic of Li-Fi networks?
A. Support for high client densities
B. High latency
C. Constrained coverage area
D. Can work on the infrared spectrum
B. Latency is the delay in data transfers, which is extremely low in Li-Fi networks
How would you best ensure the security of a ZigBee system?
A. Ensure a coordinator acts as a Trust Center
B. Use 256-bit encryption keys
C. Deploy in a ring topology with preassigned slots for each device
D. Use the Symmetric-Key Key Establishment (SKKE) protocol to derive keys
A. Using a Trust Center provides a way to centrally authenticate devices and
securely manage encryption keys, which are 128 bits (not 256). Without a Trust
Center, the SKKE protocol can be used to derive keys, but this approach is not as
secure. ZigBee does not support ring topologies.
Which of the following is a Bluetooth-specific attack that allows unauthorized
read/write access from a wireless device?
A. Bluejacking
B. Replay attack
C. Smurf attack
D. Bluesnarfing
D. Bluesnarfing could allow an attacker to read, modify, or delete calendar
events, contacts, e-mails, text messages, and so on. Bluejacking is the only other
Bluetooth attack option, but this refers to someone sending an unsolicited
message to a device.
What does the IEEE 802.1X standard cover?
A. A Management Frame Protection (MFP) that prevents replay and denial-ofservice (DoS) attacks
B. Wi-Fi Protected Access 2 (WPA2)
C. Security extensions to the physical layer (PHY) and Media Access Control (MAC) sublayer of the data link layer in the OSI model
D. An access control protocol for user authentication and key distribution
D. 802.1X is an access control protocol that can be implemented on both wired
and wireless networks for user authentication and key distribution. MFP is
covered in 802.11w, WPA2 is covered in 802.11i, and the other option (security
extensions) was a distracter
Which of the following is not a disadvantage of satellite networks compared to
terrestrial ones?
A. Latency
B. Cost
C. Bandwidth
D. Video conferencing
C. If you have the budget for it, data rates on satellite networks are comparable
with other modes of communication. These systems, however, are typically more
expensive and have high latencies, which means they are not well suited for
time-sensitive applications, such as voice and video conferencing.
Use the following scenario to answer Questions 8–10. You are planning an upgrade for
the wireless network at one of your manufacturing sites and want to use this as an
opportunity to improve network security. The current system is based on 10-year-old
wireless access points (WAPs) that implement 802.11g. You’re using WPA2 in Personal
mode because you have multiple Industrial Internet of Things (IIoT) devices. You can
update the firmware on the WAPs, but you really think it’s time for an upgrade.
- What could make it harder for you to switch from WPA2 Personal mode to
Enterprise mode?
A. Enterprise mode requires licenses that can be costly.
B. The WAPs may not support Enterprise mode.
C. IIoT devices may not support Enterprise mode.
D. The return on investment is insufficient - What is the best technology to which you should consider upgrading?
A. IEEE 802.16
B. IEEE 802.11w
C. IEEE 802.11f
D. IEEE 802.11ax - The existing wireless network has recently become unusable, and you suspect you
may be the target of a persistent Wi-Fi deauthentication attack. How can you
best mitigate this threat?
A. Deploy WPA3 access points across the facility
B. Perform MAC address filtering to keep the rogue stations off the network
C. Immediately update the firmware on the access points to support 802.11w
D. Change the channel used by the WAPs
- D. If a WAP supports WPA2, it would do so in either Personal or Enterprise
mode as long as it can be connected to the needed backend services (e.g., a
RADIUS server), with no need for additional licensing. Thus, the change would
not typically be expected to have ROI issues. However, many embedded devices,
including IIoT, do not support this mode and would have to be replaced. - D. 802.11ax is the only standard describing a WLAN among the list of
options. 802.16 is used in metropolitan area networks (MANs). 802.11w covers
Management Frame Protection (MFP) in wireless networks. 802.11f deals with
users roaming among access points. - C. 802.11w provides Management Frame Protection (MFP) capabilities that
would mitigate this type of attack. This is included in WPA3, so either answer
would generally work. However, it is probably faster, cheaper, and safer to roll
out 802.11w upgrades first, which would likely have no negative effects on the
networks, while research and planning continue on how to best implement a
WPA3 solution across the enterprise. This is a good example of the types of
ambiguous questions you’ll see on the CISSP exam.
