WGU D315 Network and Security Foundations Exam 284
Questions with Verified Answers
TCP/IP - CORRECT ANSWER model that is a common set of protocol standards
that permits the appropriate transmission of data; used for practical application
when locating specific protocol
TCP/IP layers - CORRECT ANSWER application, transport, network, network
interface
OSI - CORRECT ANSWER model that enables transmission of data among hosts on
a network; widely used in network documentation and discussions
OSI layers - CORRECT ANSWER Application, Presentation, Session, Transport,
Network, Data Link, Physical
Open Systems Interconnection (OSI) - CORRECT ANSWER OSI acronym
TCP and OSI - CORRECT ANSWER set of procedures that sends data from one host
to another. Can be done over the internet, network, or any form of
communication
TCP Network Interface Layer - CORRECT ANSWER Physical cabling and wireless
spectrum
OSI - Physical Layer - CORRECT ANSWER cables and connectors; establishes how a
signal is transmitted via wires or airwaves; responsible for the physical
connections of the devices in a network; use hubs, repeaters, modem devices and
cabling
OSI - Data link layer - CORRECT ANSWER contains network card and Media Access
Control (MAC) address; responsible for error-free delivery of data to the receiving
device or node; switches, bridges, or wireless/wired network cards
,Network Layer (TCP and OSI) - CORRECT ANSWER Internet Protocol and Internet
Control Message Protocol (ICMP); define one protocol versus another for
connecting networks
Transport Layer (TCP and OSI) - CORRECT ANSWER ensures data is transferred to
the correct application; Transmission Control Protocol (TCP) or User Diagram
Protocol (UDP)
Transmission Control Protocol (TCP) - CORRECT ANSWER type of transport layer;
verifies data and resends if not delivered
User Diagram Protocol (UDP) - CORRECT ANSWER type of transport layer;
unreliable to the extent that it does not guarantee redelivery of the data;
preferred in audio streaming
TCP - Application Layer - CORRECT ANSWER HTTP for a web broswer; SMTP for
email; DNS; Secure Shell (SSH); network time protocol (NTP); communication
protocol between nodes
OSI - Session Layer - CORRECT ANSWER establishes the session and ensures things
are working correctly end-to-end
OSI - Presentation Layer - CORRECT ANSWER takes care of data encryption;
translating data from the application layer into format required to transmit data;
OSI - Application Layer - CORRECT ANSWER HTTP; DNS; File transfer protocol
(FTP); responsible for network application; production of data to be transferred
over the network
OSI layers by number - CORRECT ANSWER Physical 1; Data Link 2; Network 3;
Transport 4; Session 5; Presentation 6; Application 7
TCP Transport Layer - CORRECT ANSWER responsible for end-to-end transport
data; TCP and UDP
,TCP Network Layer - CORRECT ANSWER logical transmission protocols for the
whole network; IP, Internet Control Message Protocol (ICMP), address resolution
protocol (ARP)
TCP Network Interface Layer - CORRECT ANSWER establishes how the data should
be physically sent through the network
OSI - Network Layer - CORRECT ANSWER responsible for the transmission of data
between hosts in different networks as well as routing data packets; use routers
and some switches
OSI - Transport Layer - CORRECT ANSWER receives services from network layer
and provides services to the application layer; responsible for reliable delivery of
data; segments and reassembles data in the correct order for it to be sent to the
receiving device; handle reliable delivery of data that are lost or corrupted (TCP
does this); heart of OSI
Switch - CORRECT ANSWER found with OSI data link; standalone or integrated
with other devices; keeps traffic between the source and destination ports from
interfering with other devices on the network;
Router - CORRECT ANSWER found with OSI network layer; connect home network
to the internet; connect web server to database server;
Firewalls - CORRECT ANSWER found in OSI layers data link, network, transport,
session, and application; defines what traffic should go between two networks;
can be software that runs in virtual machine or physical server like hardware
Firewall Layer 4 - CORRECT ANSWER operates the network and transport layers;
Firewall Layer 7 - CORRECT ANSWER operates at session, presentation, and
application layers; decrypt and analyze the content flowing through
Modem - CORRECT ANSWER A device necessary for sending and receiving data.
Allows computers to transport digital information over analog lines, such as
phone or cable lines; DSL or satelite; found in data link and physical
, Repeater - CORRECT ANSWER A device used to strengthen, replicate, and
regenerate signals that are weakened during transmission; range extender is a
form that takes distored Wi-Fi signal and transmits it to the formerly dead zone in
large homes
Hub - CORRECT ANSWER device that connects the router to the network; takes
the data packets from the router and sends them to all devices connected on the
network (e.g. USB hub)
Unshielded Twisted Pair (UTP) - CORRECT ANSWER the tighter the twists of
cables, the lesser electrical interference that occurs and higher the category of
the cable
Cat 3 cables - CORRECT ANSWER oldest UTP; analog phones; 10 mbps
Cat 4 cables - CORRECT ANSWER Token ring cabling. Speeds of 16Mbps
Cat 5 cables - CORRECT ANSWER cable used in 90s and early 2000s; used in
ethernet LANs environments; 100 mbps over 100 meters
Cat 5e cables - CORRECT ANSWER cable that supports gigabit speeds
Cat 6 - CORRECT ANSWER cabling used today; 1 gbps up to 100 meters or 10 gbps
up to 55 meters
Fiber optic cabling - CORRECT ANSWER use light; faster and more durable than
UTP; transfers data digitally; allow virtually no interference
Single-mode cabling - CORRECT ANSWER support narrow range of wavelengths
and higher bandwidths; ideal for submarine cabling across continents; used for
longer distances
Multi-mode cables - CORRECT ANSWER cheaper that single-mode across shorter
distances; from 50 to 100 microns; can run up to a couple thousand meters to a
mile; generally used in LANs
Questions with Verified Answers
TCP/IP - CORRECT ANSWER model that is a common set of protocol standards
that permits the appropriate transmission of data; used for practical application
when locating specific protocol
TCP/IP layers - CORRECT ANSWER application, transport, network, network
interface
OSI - CORRECT ANSWER model that enables transmission of data among hosts on
a network; widely used in network documentation and discussions
OSI layers - CORRECT ANSWER Application, Presentation, Session, Transport,
Network, Data Link, Physical
Open Systems Interconnection (OSI) - CORRECT ANSWER OSI acronym
TCP and OSI - CORRECT ANSWER set of procedures that sends data from one host
to another. Can be done over the internet, network, or any form of
communication
TCP Network Interface Layer - CORRECT ANSWER Physical cabling and wireless
spectrum
OSI - Physical Layer - CORRECT ANSWER cables and connectors; establishes how a
signal is transmitted via wires or airwaves; responsible for the physical
connections of the devices in a network; use hubs, repeaters, modem devices and
cabling
OSI - Data link layer - CORRECT ANSWER contains network card and Media Access
Control (MAC) address; responsible for error-free delivery of data to the receiving
device or node; switches, bridges, or wireless/wired network cards
,Network Layer (TCP and OSI) - CORRECT ANSWER Internet Protocol and Internet
Control Message Protocol (ICMP); define one protocol versus another for
connecting networks
Transport Layer (TCP and OSI) - CORRECT ANSWER ensures data is transferred to
the correct application; Transmission Control Protocol (TCP) or User Diagram
Protocol (UDP)
Transmission Control Protocol (TCP) - CORRECT ANSWER type of transport layer;
verifies data and resends if not delivered
User Diagram Protocol (UDP) - CORRECT ANSWER type of transport layer;
unreliable to the extent that it does not guarantee redelivery of the data;
preferred in audio streaming
TCP - Application Layer - CORRECT ANSWER HTTP for a web broswer; SMTP for
email; DNS; Secure Shell (SSH); network time protocol (NTP); communication
protocol between nodes
OSI - Session Layer - CORRECT ANSWER establishes the session and ensures things
are working correctly end-to-end
OSI - Presentation Layer - CORRECT ANSWER takes care of data encryption;
translating data from the application layer into format required to transmit data;
OSI - Application Layer - CORRECT ANSWER HTTP; DNS; File transfer protocol
(FTP); responsible for network application; production of data to be transferred
over the network
OSI layers by number - CORRECT ANSWER Physical 1; Data Link 2; Network 3;
Transport 4; Session 5; Presentation 6; Application 7
TCP Transport Layer - CORRECT ANSWER responsible for end-to-end transport
data; TCP and UDP
,TCP Network Layer - CORRECT ANSWER logical transmission protocols for the
whole network; IP, Internet Control Message Protocol (ICMP), address resolution
protocol (ARP)
TCP Network Interface Layer - CORRECT ANSWER establishes how the data should
be physically sent through the network
OSI - Network Layer - CORRECT ANSWER responsible for the transmission of data
between hosts in different networks as well as routing data packets; use routers
and some switches
OSI - Transport Layer - CORRECT ANSWER receives services from network layer
and provides services to the application layer; responsible for reliable delivery of
data; segments and reassembles data in the correct order for it to be sent to the
receiving device; handle reliable delivery of data that are lost or corrupted (TCP
does this); heart of OSI
Switch - CORRECT ANSWER found with OSI data link; standalone or integrated
with other devices; keeps traffic between the source and destination ports from
interfering with other devices on the network;
Router - CORRECT ANSWER found with OSI network layer; connect home network
to the internet; connect web server to database server;
Firewalls - CORRECT ANSWER found in OSI layers data link, network, transport,
session, and application; defines what traffic should go between two networks;
can be software that runs in virtual machine or physical server like hardware
Firewall Layer 4 - CORRECT ANSWER operates the network and transport layers;
Firewall Layer 7 - CORRECT ANSWER operates at session, presentation, and
application layers; decrypt and analyze the content flowing through
Modem - CORRECT ANSWER A device necessary for sending and receiving data.
Allows computers to transport digital information over analog lines, such as
phone or cable lines; DSL or satelite; found in data link and physical
, Repeater - CORRECT ANSWER A device used to strengthen, replicate, and
regenerate signals that are weakened during transmission; range extender is a
form that takes distored Wi-Fi signal and transmits it to the formerly dead zone in
large homes
Hub - CORRECT ANSWER device that connects the router to the network; takes
the data packets from the router and sends them to all devices connected on the
network (e.g. USB hub)
Unshielded Twisted Pair (UTP) - CORRECT ANSWER the tighter the twists of
cables, the lesser electrical interference that occurs and higher the category of
the cable
Cat 3 cables - CORRECT ANSWER oldest UTP; analog phones; 10 mbps
Cat 4 cables - CORRECT ANSWER Token ring cabling. Speeds of 16Mbps
Cat 5 cables - CORRECT ANSWER cable used in 90s and early 2000s; used in
ethernet LANs environments; 100 mbps over 100 meters
Cat 5e cables - CORRECT ANSWER cable that supports gigabit speeds
Cat 6 - CORRECT ANSWER cabling used today; 1 gbps up to 100 meters or 10 gbps
up to 55 meters
Fiber optic cabling - CORRECT ANSWER use light; faster and more durable than
UTP; transfers data digitally; allow virtually no interference
Single-mode cabling - CORRECT ANSWER support narrow range of wavelengths
and higher bandwidths; ideal for submarine cabling across continents; used for
longer distances
Multi-mode cables - CORRECT ANSWER cheaper that single-mode across shorter
distances; from 50 to 100 microns; can run up to a couple thousand meters to a
mile; generally used in LANs
