WGU D415 SOFTWARE DEFINED
NETWORKING PA AND OA EXAMINATION
TEST 2026 COMPLETE QUESTIONS AND
SOLUTIONS GRADED A+
⩥ dpctl. Answer: talks to a switch
Switch listens on port 6634
can inspect table flow entries
modify flows
⩥ dpctl commands. Answer: dpctl show tcp:127.0.0.1:6634
dpctl dump-flows tcp:127.0.0.1:6634
dpctl add-flows tcp:127.0.0.1:6634 in_port=1,actions=output:2
Note: switches listen on port 6634
⩥ OpenFlow v1.3 Enhancements. Answer: Action Set
Group: a list of action sets
Each table entry updates fields, modifies action set
⩥ Action Group Options. Answer: 1. Execute all actions in a group
(useful for multicast)
2. Indirect group (exec one defined bucket in a group)
,⩥ Hub. Answer: Forwards all traffic to output ports.
No forwarding information is store in the hub
Every input packet is flooded to all output ports
sudo mn --topo single,3 --mac --switch ovsk --controller remote
⩥ Learning Switch. Answer: Learns forwarding table entries
sudo python pox.py forwarding.l2_learning
⩥ Firewall. Answer: 1. Important to limit data traffic to the controller
2. When controller decides to forward or drop, the switch's flow table
entry is modified
3. Decision is cached at the switch until the flow table entry expires
Flow table entries expire in 30sec
⩥ SDN Firewall. Answer: 1. Customization is easy in SDN
2. Exploration of alternative control program
3. Demonstrate performance benefits of caching at the switch
⩥ OpenDaylight. Answer: Heavy industry involvement
⩥ Hydrogen Release. Answer: OpenDaylight API (REST)
, Service Abstraction Layer
OpenFlow
Switch
⩥ OpenDaylight Details. Answer: Controller written in Java (cross-
platform)
Maven - build system for Java
OSGi - dynamically loaded bundles
⩥ Java Interfaces are used for event listening, specs, forming patterns.
Answer:
⩥ Life of an OpenDaylight packet. Answer: 1. packet arriving at the
switch will be sent to appropriate plugin
2. plugin will parse the packet and generate an event for SAL
3. SAL will dispatch packet to the modules listening to the Datapacket
4. Modules handles packet and Sends packet_out using
iDataPacketService
⩥ Ryu Controller. Answer: Open Stack Neutron agent and OF-Rest
Ryu Applications
Ryu Manager
App Manager
NETWORKING PA AND OA EXAMINATION
TEST 2026 COMPLETE QUESTIONS AND
SOLUTIONS GRADED A+
⩥ dpctl. Answer: talks to a switch
Switch listens on port 6634
can inspect table flow entries
modify flows
⩥ dpctl commands. Answer: dpctl show tcp:127.0.0.1:6634
dpctl dump-flows tcp:127.0.0.1:6634
dpctl add-flows tcp:127.0.0.1:6634 in_port=1,actions=output:2
Note: switches listen on port 6634
⩥ OpenFlow v1.3 Enhancements. Answer: Action Set
Group: a list of action sets
Each table entry updates fields, modifies action set
⩥ Action Group Options. Answer: 1. Execute all actions in a group
(useful for multicast)
2. Indirect group (exec one defined bucket in a group)
,⩥ Hub. Answer: Forwards all traffic to output ports.
No forwarding information is store in the hub
Every input packet is flooded to all output ports
sudo mn --topo single,3 --mac --switch ovsk --controller remote
⩥ Learning Switch. Answer: Learns forwarding table entries
sudo python pox.py forwarding.l2_learning
⩥ Firewall. Answer: 1. Important to limit data traffic to the controller
2. When controller decides to forward or drop, the switch's flow table
entry is modified
3. Decision is cached at the switch until the flow table entry expires
Flow table entries expire in 30sec
⩥ SDN Firewall. Answer: 1. Customization is easy in SDN
2. Exploration of alternative control program
3. Demonstrate performance benefits of caching at the switch
⩥ OpenDaylight. Answer: Heavy industry involvement
⩥ Hydrogen Release. Answer: OpenDaylight API (REST)
, Service Abstraction Layer
OpenFlow
Switch
⩥ OpenDaylight Details. Answer: Controller written in Java (cross-
platform)
Maven - build system for Java
OSGi - dynamically loaded bundles
⩥ Java Interfaces are used for event listening, specs, forming patterns.
Answer:
⩥ Life of an OpenDaylight packet. Answer: 1. packet arriving at the
switch will be sent to appropriate plugin
2. plugin will parse the packet and generate an event for SAL
3. SAL will dispatch packet to the modules listening to the Datapacket
4. Modules handles packet and Sends packet_out using
iDataPacketService
⩥ Ryu Controller. Answer: Open Stack Neutron agent and OF-Rest
Ryu Applications
Ryu Manager
App Manager
