WGU D315 COMPREHENSIVE QUESTIONS
AND SOLUTIONS
◉ OSI Layer 6
Answer: Presentation - Data representation & encryption (SSH,
SSL, IMap, FTP, JPeg)
◉ OSI Layer 5
Answer: Session - Connection maintenance (API's sockets)
◉ OSI Layer 4
Answer: Transport - End to end connection (TCP, UDP)
◉ OSI Layer 3
Answer: Network - Logical addressing for data path using packets
(IP, ICMP, IGMP)
◉ OSI Layer 2
Answer: Data Link - Physical addressing , formatting data in
frames (Switches, Bridges, Ethernet)
◉ OSI Layer 1
,Answer: Physical - Physical transmission of signals, media or
binary raw bits (Coax, Fiber, Wireless)
◉ TCP/IP Layer 4
Answer: Application - OSI layers 7, 6, and 5 - HTTPS, FTP, Telnet,
NTP, DHCP, Ping
◉ TCP/IP Layer 3
Answer: Transport - OSI layer 4 - TCP, UDP (Port address)
◉ TCP/IP Layer 2
Answer: Network - OSI layer 3 - IP, ARP, ICMP, IGMP (IP Address)
◉ TCP/IP Layer 1
Answer: network Interface - OSI layer 1 &2 - Ethernet (MAC
Address)
◉ Hub
Answer: Layer 1 - Connection point for a wired network (Dumb
Device). Not used in IT anymore
◉ Switch
Answer: Layer 2 - Primary device for inter connecting wired
components (Smart Device). Learns which MAC address live on
, which port and keeps a table of a MAC address to port
assignment. Only send data to the correct recipient.
◉ Wireless Access Point
Answer: Layer 2 - Acts as a bridge, It takes all wireless clients and
bridges them to the wired network. Uses MAC addresses to make
forwarding decisions.
◉ Router
Answer: Layer 3 - move data between one IP network to another
◉ Modem
Answer: Layer 2 - allows your ISP to provide service to your house
or business.
◉ Bridge
Answer: Layer 2 - A device that connects multiple networks or
network segments into a single network
◉ Repeater
Answer: Layer 1 - A network node that amplifies incoming signals
and rebroadcast them over a wider area.
◉ Cat 3
Answer: 10 Mbps up to 100m
AND SOLUTIONS
◉ OSI Layer 6
Answer: Presentation - Data representation & encryption (SSH,
SSL, IMap, FTP, JPeg)
◉ OSI Layer 5
Answer: Session - Connection maintenance (API's sockets)
◉ OSI Layer 4
Answer: Transport - End to end connection (TCP, UDP)
◉ OSI Layer 3
Answer: Network - Logical addressing for data path using packets
(IP, ICMP, IGMP)
◉ OSI Layer 2
Answer: Data Link - Physical addressing , formatting data in
frames (Switches, Bridges, Ethernet)
◉ OSI Layer 1
,Answer: Physical - Physical transmission of signals, media or
binary raw bits (Coax, Fiber, Wireless)
◉ TCP/IP Layer 4
Answer: Application - OSI layers 7, 6, and 5 - HTTPS, FTP, Telnet,
NTP, DHCP, Ping
◉ TCP/IP Layer 3
Answer: Transport - OSI layer 4 - TCP, UDP (Port address)
◉ TCP/IP Layer 2
Answer: Network - OSI layer 3 - IP, ARP, ICMP, IGMP (IP Address)
◉ TCP/IP Layer 1
Answer: network Interface - OSI layer 1 &2 - Ethernet (MAC
Address)
◉ Hub
Answer: Layer 1 - Connection point for a wired network (Dumb
Device). Not used in IT anymore
◉ Switch
Answer: Layer 2 - Primary device for inter connecting wired
components (Smart Device). Learns which MAC address live on
, which port and keeps a table of a MAC address to port
assignment. Only send data to the correct recipient.
◉ Wireless Access Point
Answer: Layer 2 - Acts as a bridge, It takes all wireless clients and
bridges them to the wired network. Uses MAC addresses to make
forwarding decisions.
◉ Router
Answer: Layer 3 - move data between one IP network to another
◉ Modem
Answer: Layer 2 - allows your ISP to provide service to your house
or business.
◉ Bridge
Answer: Layer 2 - A device that connects multiple networks or
network segments into a single network
◉ Repeater
Answer: Layer 1 - A network node that amplifies incoming signals
and rebroadcast them over a wider area.
◉ Cat 3
Answer: 10 Mbps up to 100m
