Domain 4 - Communication & Network Security Flashcards
Gary wants to distribute a large file and prefers a peer-to-peer
CDN. Which of the following is the most common example of
this type of technology?
A. CloudFlare
B. BitTorrent
C. Amazon CloudFront
D. Akamai Edge
B. BitTorrent
B. BitTorrent is an example of a peer-to-peer (P2P) content
delivery network. It is commonly used for legitimate purposes to
distribute large files like Linux ISOs and other freely distributed
software packages and files in addition to its less legitimate uses.
CloudFlare, CloudFront, and Akamai’s Edge are all hosted
CDNs.
During a security assessment of a wireless network, Jim
discovers that LEAP is in use on a network using WPA. What
recommendation should Jim make?
A. Continue to use LEAP. It provides better security than TKIP for WPA networks.
B. Use an alternate protocol like PEAP or EAP-TLS and implement WPA2 if supported.
C. Continue to use LEAP to avoid authentication issues, but move to WPA2.
D. Use an alternate protocol like PEAP or EAP-TLS, and implement Wired Equivalent Privacy to avoid wireless security issues.
B. Use an alternate protocol like PEAP or EAP-TLS and implement WPA2 if supported.
B. LEAP, the Lightweight Extensible Authentication Protocol, is
a Cisco proprietary protocol designed to handle problems with
TKIP. Unfortunately, LEAP has significant security issues as
well and should not be used. Any modern hardware should
support WPA2 and technologies like PEAP or EAP-TLS. Using
WEP, the predecessor to WPA and WPA2, would be a major step
back in security for any network.
Ben has connected his laptop to his tablet PC using an 802.11ac
connection. What wireless network mode has he used to connect
these devices?
A. Infrastructure mode
B. Wired extension mode
C. Ad hoc mode
D. Standalone mode
C. Ad hoc mode
C. Ben is using ad hoc mode, which directly connects two
clients. It can be easy to confuse this with standalone mode,
which connects clients using a wireless access point but not to
wired resources like a central network. Infrastructure mode
connects endpoints to a central network, not directly to each
other. Finally, wired extension mode uses a wireless access point
to link wireless clients to a wired network.
Selah’s and Nick’s PCs simultaneously send traffic by
transmitting at the same time. What network term describes the
range of systems on a network that could be affected by this
same issue?
A. The subnet
B. The supernet
C. A collision domain
D. A broadcast domain
C. A collision domain
C. A collision domain is the set of systems that could cause a
collision if they transmitted at the same time. Systems outside a
collision domain cannot cause a collision if they send at the
same time. This is important, as the number of systems in a
collision domain increases the likelihood of network congestion
due to an increase in collisions. A broadcast domain is the set of
systems that can receive a broadcast from each other. A subnet
is a logical division of a network, while a supernet is made up of
two or more networks
Sarah is manually reviewing a packet capture of TCP traffic and
finds that a system is setting the RST flag in the TCP packets it
sends repeatedly during a short period of time. What does this
flag mean in the TCP packet header?
A. RST flags mean “Rest.” The server needs traffic to briefly
pause.
B. RST flags mean “Relay-set.” The packets will be forwarded
to the address set in the packet.
C. RST flags mean “Resume Standard.” Communications will
resume in their normal format.
D. RST means “Reset.” The TCP session will be disconnected.
D. RST means “Reset.” The TCP session will be disconnected.
D. The RST flag is used to reset or disconnect a session. It can
be resumed by restarting the connection via a new three-way
handshake.
Gary is deploying a wireless network and wants to deploy the
fastest possible wireless technology. Which one of the following
wireless networking standards should he use?
A. 802.11a
B. 802.11g
C. 802.11n
D. 802.11ac
D. 802.11ac
D. He should choose 802.11ac, which supports theoretical
speeds up to 3.4 Gbps. 802.11n supports up to 600 Mbps,
802.11g and 802.11a are only capable of 54 Mbps.
Michele wants to replace FTP traffic with a secure replacement.
What secure protocol should she select instead?
A. TFTP
B. HFTPS
C. SecFTP
D. SFTP
D. SFTP
D. Both FTP/S and SFTP are commonly used as replacement
insecure FTP services. SFTP offers the advantage of using SSH
for transfers, making it easy to use existing firewall rules. TFTP
is trivial FTP, an insecure quick transfer method often used to
transfer files for network devices, among other uses. HFTPS and
SecFTP were made up for this question.
Jake has been told that there is a layer 3 problem with his
network. Which of the following is associated with layer 3 in the
OSI model?
A. IP addresses
B. TCP and UDP protocols
C. MAC addresses
D. Sending and receiving bits via hardware
A. IP addresses
A. The Network layer, or layer 3, uses IP addresses for logical
addressing. TCP and UDP protocols are used at the Transport
layer, which is layer 4. Hardware addresses are used at layer 2,
the Data Link layer, and sending and receiving bits via hardware
is done at the Physical layer (layer 1).
Frank is responsible for ensuring that his organization has
reliable, supported network hardware. Which of the following is
not a common concern for network administrators as they work
to ensure their network continues to be operational?
A. If the devices have vendor support
B. If the devices are under warranty
C. If major devices support redundant power supplies
D. If all devices support redundant power supplies
D. If all devices support redundant power supplies
D. Most networks include many edge devices like wireless
access points and edge switches. These devices often have a
single power supply to balance cost against reliability and will
simply be replaced if they fail. More critical devices like routers
and core switches are typically equipped with redundant power
supplies to ensure that larger segments of the network do not
fail if a component fails. Of course, making sure devices are
supported so they get updates and that they are under warranty
are both common practices for supportable networks.
Brian is selecting an authentication protocol for a PPP
connection. He would like to select an option that encrypts both
usernames and passwords and protects against replay using a
challenge/response dialog. He would also like to reauthenticate
remote systems periodically. Which protocol should he use?
A. PAP
B. CHAP
C. EAP
D. LEAP
B. CHAP
B. The Challenge-Handshake Authentication Protocol, or
CHAP, is used by PPP servers to authenticate remote clients. It
encrypts both the username and password and performs
periodic reauthentication while connected using techniques to
prevent replay attacks. LEAP provides reauthentication but was
designed for WEP, while PAP sends passwords unencrypted.
EAP is extensible and was used for PPP connections, but it
doesn’t directly address the listed items.
Which one of the following protocols is commonly used to
provide back-end authentication services for a VPN?
A. HTTPS
B. RADIUS
C. ESP
D. AH
B. RADIUS
B. The Remote Access Dial In User Service (RADIUS) protocol
was originally designed to support dial-up modem connections
but is still commonly used for VPN-based authentication.
HTTPS is not an authentication protocol. ESP and AH are IPsec
protocols but do not provide authentication services for other
systems.
Isaac wants to ensure that his VoIP session initialization is
secure. What protocol should he ensure is enabled and
required?
A. SVOIP
B. PBSX
C. SIPS
D. SRTP
C. SIPS
C. SIPS, the secure version of the Session Initialization Protocol
for VoIP, adds TLS encryption to keep the session initialization
process secure. SVOIP and PBSX are not real protocols, but
SRTP is the secure version of RTP, the Real time Transport
Protocol.
Internet
|A|
Firewall -|B|- Web Server
Router -|C|- VPN Concentrator
||
Switch
||
Workstations
What type of firewall design is shown in the diagram?
A. A single-tier firewall
B. A two-tier firewall
C. A three-tier firewall
D. A four-tier firewall
B. A two-tier firewall
B. The firewall in the diagram has two protected zones behind
it, making it a two-tier firewall design.
Internet
|A|
Firewall -|B|- Web Server
Router -|C|- VPN Concentrator
Switch
Workstations
If the VPN grants remote users the same access to network and
system resources as local workstations have, what security issue
should Chris raise?
A. VPN users will not be able to access the web server.
B. There is no additional security issue; the VPN
concentrator’s logical network location matches the logical
network location of the workstations.
C. Web server traffic is not subjected to stateful inspection.
D. VPN users should only connect from managed PCs.
D. VPN users should only connect from managed PCs.
D. Remote PCs that connect to a protected network need to
comply with security settings and standards that match those
required for the internal network. The VPN concentrator
logically places remote users in the protected zone behind the
firewall, but that means user workstations (and users) must be
trusted in the same way that local workstations are.
Internet
|A|
Firewall -|B|- Web Server
Router -|C|- VPN Concentrator
Switch
Workstations
If Chris wants to stop cross-site scripting attacks against the web
server, what is the best device for this purpose, and where
should he put it?
A. A firewall, location A
B. An IDS, location A
C. An IPS, location B
D. A WAF, location C
|
C. An IPS, location B
C. An intrusion protection system can scan traffic and stop both
known and unknown attacks. A web application firewall, or
WAF, is also a suitable technology, but placing it at location C
would only protect from attacks via the organization’s VPN,
which should only be used by trusted users. A firewall typically
won’t have the ability to identify and stop cross-site scripting
attacks, and IDS systems only monitor and don’t stop attacks.
Susan is deploying a routing protocol that maintains a list of
destination networks with metrics that include the distance in
hops to them and the direction traffic should be sent to them.
What type of protocol is she using?
A. A link-state protocol
B. A link-distance protocol
C. A destination metric protocol
D. A distance-vector protocol
D. A distance-vector protocol
D. Distance-vector protocols use metrics including the direction
and distance in hops to remote networks to make decisions. A
link-state routing protocol considers the shortest distance to a
remote network. Destination metric and link-distance protocols
don’t exist.
Ben has configured his network to not broadcast an SSID. Why
might Ben disable SSID broadcast, and how could his SSID be
discovered?
A. Disabling SSID broadcast prevents attackers from discovering the encryption key. The SSID can be recovered from decrypted packets.
B. Disabling SSID broadcast hides networks from unauthorized personnel. The SSID can be discovered using a wireless sniffer.
C. Disabling SSID broadcast prevents issues with beacon frames. The SSID can be recovered by reconstructing the BSSID.
D. Disabling SSID broadcast helps avoid SSID conflicts. The SSID can be discovered by attempting to connect to the network.
B. Disabling SSID broadcast hides networks from unauthorized personnel. The SSID can be discovered using a wireless sniffer.
B. Disabling SSID broadcast can help prevent unauthorized
personnel from attempting to connect to the network. Since the
SSID is still active, it can be discovered by using a wireless
sniffer. Encryption keys are not related to SSID broadcast,
beacon frames are used to broadcast the SSID, and it is possible
to have multiple networks with the same SSID.
What network tool can be used to protect the identity of clients
while providing Internet access by accepting client requests,
altering the source addresses of the requests, mapping requests
to clients, and sending the modified requests out to their
destination?
A. A switch
B. A proxy
C. A router
D. A firewall
B. A proxy
B. A proxy is a form of gateway that provides clients with a
filtering, caching, or other service that protects their information
from remote systems. A router connects networks, while a
firewall uses rules to limit traffic permitted through it. A switch
is used to connect systems and does not provide these
capabilities.
Susan wants to secure her communications traffic via multiple
internet service providers as it is sent to her company’s second
location. What technology should she use to protect the traffic
for an always on, always connected link between the sites?
A. FCoE
B. SDWAN
C. A point-to-point IPsec VPN
D. Zigbee
C. A point-to-point IPsec VPN
C. A point-to-point IPsec VPN can provide a secure, encrypted
channel that is established on an ongoing basis between the two
sites, ensuring that Susan’s traffic is not exposed along the path
that it travels. FCoE is Fibre Channel over Ethernet, a storage
protocol. SD-WAN is a software-defined wide area network, and
Zigbee is a low-power wireless protocol. None of these addresses
Susan’s needs.
Melissa wants to combine multiple physical networks in her
organization in a way that is transparent to users but allows the
resources to be allocated as needed for networked services.
What type of network should she deploy?
A. iSCSI
B. A virtual network
C. SDWAN
D. A CDN
B. A virtual network
B. A virtual network can be used to combine existing networks
or to divide a network into multiple segments. Melissa can use a
virtual network to combine existing networks and then use
software-defined networking capabilities to allocate and manage
network resources. iSCSI is a converged storage protocol. An
SD-WAN is a software-defined wide area network, and this
question does not specify LAN or WAN technologies. A CDN is a
content distribution network and helps with load and denial-ofservice attacks.
Which email security solution provides two major usage modes:
(1) signed messages that provide integrity, sender
authentication, and nonrepudiation; and (2) an enveloped
message mode that provides integrity, sender authentication,
and confidentiality?
A. S/MIME
B. MOSS
C. PEM
D. DKIM
A. S/MIME
A. S/MIME supports both signed messages and a secure
envelope method. While the functionality of S/MIME can be
replicated with other tools, the secure envelope is an S/MIMEspecific concept. MOSS, or MIME Object Security Services, and
PEM can also both provide authentication, confidentiality,
integrity, and nonrepudiation, while DKIM, or Domain Keys
Identified Mail, is a domain validation tool
During a security assessment, Jim discovers that the
organization he is working with uses a multilayer protocol to
handle SCADA systems and recently connected the SCADA
network to the rest of the organization’s production network.
What concern should he raise about serial data transfers carried
via TCP/IP?
A. SCADA devices that are now connected to the network can now be attacked over the network.
B. Serial data over TCP/IP cannot be encrypted.
C. Serial data cannot be carried in TCP packets.
D. TCP/IP’s throughput can allow for easy denial-of-service attacks against serial devices.
A. SCADA devices that are now connected to the network can now be attacked over the network.
A. Multilayer protocols like DNP3 allow SCADA and other
systems to use TCP/IP-based networks to communicate. Many
SCADA devices were never designed to be exposed to a network,
and adding them to a potentially insecure network can create
significant risks. TLS or other encryption can be used on TCP
packets, meaning that even serial data can be protected. Serial
data can be carried via TCP packets because TCP packets don’t
care about their content; it is simply another payload. Finally,
TCP/IP does not have a specific throughput as designed, so
issues with throughput are device-level issues.
Alicia’s company has implemented multifactor authentication
using SMS messages to provide a numeric code. What is the
primary security concern that Alicia may want to express about
this design?
A. SMS messages are not encrypted.
B. SMS messages can be spoofed by senders.
C. SMS messages may be received by more than one phone.
D. SMS messages may be stored on the receiving phone.
A. SMS messages are not encrypted.
A. SMS messages are not encrypted, meaning that they could be
sniffed and captured. While using two factors is more secure
than a single factor, SMS is one of the less secure ways to
implement two-factor authentication because of this. SMS
messages can be spoofed, can be received by more than one
phone, and are typically stored on the recipient’s phone. The
primary threat here, however, is the unencrypted message itself.
The Address Resolution Protocol (ARP) and the Reverse
Address Resolution Protocol (RARP) operate at what layer of the
OSI model?
A. Layer 1
B. Layer 2
C. Layer 3
D. Layer 4
B. Layer 2
B. ARP and RARP operate at the Data Link layer, the second
layer of the OSI model. Both protocols deal with physical
hardware addresses, which are used above the Physical layer
(layer 1) and below the Network layer (layer 3), thus falling at
the Data Link layer.
Which of the following is a converged protocol that allows
storage mounts over TCP, and which is frequently used as a
lower-cost alternative to Fibre Channel?
A. MPLS
B. SDN
C. VoIP
D. iSCSI
D. iSCSI
D. iSCSI is a converged protocol that allows locationindependent file services over traditional network technologies.
It costs less than traditional Fibre Channel. VoIP is Voice over
IP, SDN is software-defined networking, and MPLS is
Multiprotocol Label Switching, a technology that uses path
labels instead of network addresses.
What speed and frequency range are used by 802.11n?
A. 5 GHz only
B. 900 MHz and 2.4 GHz
C. 2.4 GHz and 5 GHz
D. 2.4 GHz only
C. 2.4 GHz and 5 GHz
C. 802.11n can operate on both the 2.4 and 5 GHz frequency
range. The 900 MHz range has frequently been used for phones
and non-WiFi wireless networks as well as other amateur radio
uses. Knowing that multiple ranges are available and that they
may behave differently based on how many access points are in
use and whether other devices that may cause interference on
that band are in the area can be important for wireless network
deployments
Which of the following drawbacks is a concern when multilayer
protocols are allowed?
A. A range of protocols may be used at higher layers.
B. Covert channels are allowed.
C. Filters cannot be bypassed.
D. Encryption can’t be incorporated at multiple layers.
B. Covert channels are allowed.
B. Multilayer protocols create three primary concerns for
security practitioners: they can conceal covert channels (and
thus covert channels are allowed), filters can be bypassed by
traffic concealed in layered protocols, and the logical boundaries
put in place by network segments can be bypassed under some
circumstances. Multilayer protocols allow encryption at various
layers and support a range of protocols at higher layers
Ben provides networking and security services for a small chain
of coffee shops. The coffee shop chain wants to provide secure,
free wireless for customers. Which of the following is the best
option available to Ben to allow customers to connect securely to
his wireless network without needing a user account if Ben does
not need to worry about protocol support issues?
A. Use WPA2 in PSK mode.
B. Use WPA3 in SAE mode.
C. Use WPA2 in Enterprise mode.
D. Use a captive portal.
B. Use WPA3 in SAE mode.
B. WPA3’s new SAE (simultaneous authentication of equals)
mode improves on WPA2’s PSK mode by allowing for secure
authentication between clients and the wireless network without
enterprise user accounts. If Ben needed to worry about support
for WPA3, which may not be available to all systems that may
want to connect, he might have to choose WPA2. A captive
portal is often used with open guest networks, and Enterprise
mode requires user accounts.
Chris is building an Ethernet network and knows that he needs
to span a distance of more than 150 meters with his 1000BaseT
network. What network technology should he use to help with
this?
A. Install a repeater, a switch, or a concentrator before 100 meters.
B. Use Category 7 cable, which has better shielding for higher speeds.
C. Install a gateway to handle the distance.
D. Use STP cable to handle the longer distance at high speeds.
A. Install a repeater, a switch, or a concentrator before 100 meters.
A. A repeater, switch, or concentrator will amplify the signal,
ensuring that the 100-meter distance limitation of 1000BaseT is
not an issue. A gateway would be useful if network protocols
were changing, while Cat7 cable is appropriate for a 10 Gbps
network at much shorter distances. STP cable is limited to 155
Mbps and 100 meters, which would leave Chris with network
problems.
Which of the following is not an example of a converged protocol?
A. MIME
B. FCoE
C. iSCSI
D. VoIP
A. MIME
A. Fibre Channel over Ethernet (FCoE), Internet Small
Computer Systems Interface (iSCSI), and Voice over Internet
Protocol (VoIP) are all examples of converged protocols that
combine specialized protocols with standard protocols like
TCP/IP. MIME, Multipurpose Internet Mail Extensions, is not a
converged protocol.
Joanna wants to deploy 4G LTE as an out-of-band management
solution for devices at remote sites. Which of the following
security capabilities is not commonly available from 4G service
providers?
A. Encryption capabilities
B. Device-based authentication
C. Dedicated towers and antennas for secure service subscribers
D. SIM-based authentication
C. Dedicated towers and antennas for secure service subscribers
C. While security features vary from provider to provider,
encryption, device-based authentication (for example, using
certificates), and SIM-based authentication are all common
options for 4G connectivity solutions. Joanna should work with
her provider to determine what capabilities are available and
assess whether they meet her needs.
Sue modifies her MAC address to one that is allowed on a
network that uses MAC filtering to provide security. What is the
technique Sue used, and what nonsecurity issue could her
actions cause?
A. Broadcast domain exploit, address conflict
B. Spoofing, token loss
C. Spoofing, address conflict
D. Sham EUI creation, token loss
C. Spoofing, address conflict
C. The process of using a fake MAC (Media Access Control)
address is called spoofing, and spoofing a MAC address already
in use on the network can lead to an address collision,
preventing traffic from reaching one or both systems. Tokens are
used in token ring networks, which are outdated, and EUI refers
to an Extended Unique Identifier, another term for MAC
address, but token loss is still not the issue. Broadcast domains
refer to the set of machines a host can send traffic to via a
broadcast message.
The company that Kathleen works for has moved to remote
work for most employees and wants to ensure that the
multimedia collaboration platform that they use for voice, video,
and text-based collaboration is secure. Which of the following
security options will provide the best user experience while
providing appropriate security for communications?
A. Require software-based VPN to the corporate network for all use of the collaboration platform.
B. Require the use of SIPS and SRTP for all communications.
C. Use TLS for all traffic for the collaboration platform.
D. Deploy secure VPN endpoints to each remote location and use a point-to-point VPN for communications.
C. Use TLS for all traffic for the collaboration platform.
C. Most modern applications support TLS throughout their
communications allowing clients to securely connect to the
service and to encrypt communications. VPN, either in software
or hardware form, will be more complex and unwieldy.
Software-based VPN would be more flexible, and hardwarebased VPN would be more expensive and more complex. SIPS
and SRTP are appropriate for a VoIP environment, but are not
generally a complete solution for a modern multimedia
collaboration platform like Microsoft Teams, Zoom, or WebEx
Selah wants to provide port-based authentication on her
network to ensure that clients must authenticate before using
the network. What technology is an appropriate solution for this
requirement?
A. 802.11a
B. 802.3
C. 802.15.1
D. 802.1x
D. 802.1x
D. 802.1x provides port-based authentication and can be used
with technologies like EAP, the Extensible Authentication
Protocol. 802.11a is a wireless standard, 802.3 is the standard
for Ethernet, and 802.15.1was the original Bluetooth IEEE
standard.
Chris uses a cellular hot spot to provide internet access when he
is traveling. If he leaves the hot spot connected to his PC while
his PC is on his organization’s corporate network, what security
issue might he cause?
A. Traffic may not be routed properly, exposing sensitive data.
B. His system may act as a bridge from the internet to the local network.
C. His system may be a portal for a reflected DDoS attack.
D. Security administrators may not be able to determine his IP
address if a security issue occurs.
B. His system may act as a bridge from the internet to the local network.
B. When a workstation or other device is connected
simultaneously to both a secure network and a nonsecure
network like the internet, it may act as a bridge, bypassing the
security protections located at the edge of a corporate network.
It is unlikely that traffic will be routed improperly leading to the
exposure of sensitive data, as traffic headed to internal systems
and networks is unlikely to be routed to the external network.
Reflected DDoS attacks are used to hide identities rather than to
connect through to an internal network, and security
administrators of managed systems should be able to determine
both the local and wireless IP addresses his system uses.
Internet -|TCP 80|- Computer B
||
Firewall
Router
Switch — Computer C
|TCP80|
Computer A
What protocol is the messaging traffic most likely to use based
on the diagram?
A. SLACK
B. HTTP
C. SMTP
D. HTTPS
B. HTTP
B. The use of TCP port 80 indicates that the messaging service
is using the HTTP protocol. Slack is a messaging service that
runs over HTTPS, which uses port 443. SMTP is an email
protocol that uses port 25.
Internet -|TCP 80|- Computer B
||
Firewall
Router
Switch — Computer C
|TCP80|
Computer A
- How could Selah’s company best address a desire for secure
messaging for users of internal systems A and C?
A. Use a third-party messaging service.
B. Implement and use a locally hosted service.
C. Use HTTPS.
D. Discontinue use of messaging and instead use email, which
is more secure.
B. Implement and use a locally hosted service.
B. If a business need requires messaging, using a local
messaging server is the best option. This prevents traffic from
traveling to a third-party server and can offer additional benefits
such as logging, archiving, and control of security options like
the use of encryption.
Casey has been asked to determine if Zigbee network traffic can
be secured in transit. What security mechanism does Zigbee use
to protect data traffic?
A. 3DES encryption
B. AES encryption
C. ROT13 encryption
D. Blowfish encryption
B. AES encryption
B. Zigbee uses AES to protect network traffic, providing
integrity and confidentiality controls. It does not use 3DES, and
ROT13 is a simple rotational cipher you might find in a cereal
box or secret decoder ring.
What security control does MAC cloning attempt to bypass for
wired networks?
A. Port security
B. VLAN hopping
C. 802.1q trunking
D. Etherkiller prevention
A. Port security
A. Port security prevents unrecognized or unpermitted systems
from connecting to a network port based on their MAC address.
Cloning a permitted or legitimate MAC address attempts to
bypass this. VLAN hopping and 802.1q trunking attacks attempt
to access other subnets by encapsulating packets so they will be
unwrapped and directed to the other subnet. Etherkiller
prevention is not a security setting or control.
Melissa uses the ping utility to check whether a remote system is
up as part of a penetration testing exercise. If she does not want
to see her own ping packets, what protocol should she filter out
from her packet sniffer’s logs?
A. UDP
B. TCP
C. IP
D. ICMP
D. ICMP
D. Ping uses ICMP, the Internet Control Message Protocol, to
determine whether a system responds and how many hops there
are between the originating system and the remote system.
Melissa simply needs to filter out ICMP to not see her pings.