MEF-SDN/NFV Flashcards
- An organization just failed an SEC test audit. Packet flooding and redundancy in an emergency are two problems
cited in the audit. The security staff in the organization is advocating for expensive appliances to be purchased. The
CTO wants the network architect to investigate SDN. Which characteristics of SDN are reasons to adopt the CTO’s
recommendation?
Security-defined interoperability will deliver routes that leverage the existing infrastructure and optimize
traffic
Packet-based routing will be providing a better accounting of all traffic in the network through better audit
log information for the auditors
SDN will deliver better isolation of data plane traffic and will provide more flexibility to address
redundancy needs
The ability to separate control plane from the data plane automatically makes data management easier and
more secure
SDN will deliver better isolation of data plane traffic and will provide more flexibility to address
redundancy needs
- A Service Provider is upgrading a set of SDN Switches in a given region. The maintenance window for network
upgrades is 2 am to 4 am. The downtime must be minimized as much as possible. What should the network
administrator do to minimize the downtime?
Reactively program a flow in the controller to redirect traffic toward the region at 1 am
Proactively program a flow in the controller to redirect traffic away from the region at 1 am
Proactively program a flow in the SDN Switches to redirect traffic away from the region at 1 am
Reactively program a flow in the SDN Switches to redirect traffic toward the region at 1 am
Proactively program a flow in the controller to redirect traffic away from the region at 1 am
- A customer requests its VPN provider to prohibit FTP traffic between its branch offices. The VPN provider’s
network is fully SDN controlled, but does NOT offer a self-service portal to its customers.
Which SDN component does the VPN provider’s SDN support engineer need to interact with?
The policy/intent interface of the SDN Controller
The user interface of the OpenFlow instance
The command line interface (CLI) of the VPN gateways
The SNMP interface of the optical network EMS
The policy/intent interface of the SDN Controller
- The network operator is troubleshooting a connection issue for a user TCP/IP connection through the SDN
Network. Which component implements the routing logic for the IP path?
Control plane in the SDN Switch
Control plane in the SDN Controller
Forwarding plane in the SDN Controller
Forwarding plane in the SDN Switch
Control plane in the SDN Controller
- A media content provider struggles with data growth on its SDN network and adds an SDN controller to distribute
the load and increase robustness. Which communication interface should the SDN controllers use to synchronize
their operation and provide a single controller view to the applications?
Eastbound/Westbound interface
Infrastructure layer interface
Application layer interface
Northbound/Southbound interface
Eastbound/Westbound interface
- A Service Provider plans to provide a service portal to allow customers to interact with an SDN network to be
able to view the status and statistics of their services. Which interface does the service portal use to retrieve this
information?
The SDN Switches east/west interfaces
The SDN Controller northbound interface
The SDN Controller OpenFlow interface
The SDN Switches southbound interface
The SDN Controller northbound interface
- A company is evaluating the move to SDN. The CTO fears that the implementation of the OpenFlow protocol
throughout the environment may have a performance impact that affects business operations. How can the
company mitigate risk while still being able to deploy SDN technologies?
Deploy a separate network for OpenFlow protocol traffic
Find a network edge use case that would allow an interoperable OpenFlow solution to be deployed for
deep packet inspection
Find a hybrid networking solution by deploying custom APIs to manage switch traffic from the nonOpenFlow switches
Deploy an overlay SDN solution like VxLAN.
Deploy a separate network for OpenFlow protocol traffic
- A customer has an existing network and wants to extend it with new OpenFlow switches. What southbound
protocol must customer use to manage the legacy switches?
YANG
OpenFlow
OF-Config
NETCONF
NETCONF
- A Service Provider is implementing an SDN solution. Due to budget constraints, the Service Provider will
implement incremental network upgrades and leverage the legacy switching network. Which southbound protocols
must the SDN Controller support to facilitate this architecture?
Ansible and NETCONF
NFV and OpenFlow
OpenFlow and SNMP
OpenFlow and YANG
OpenFlow and SNMP
- A company is planning to roll out all of its new applications to take advantage of SDN. They need to use
OpenFlow 1.3. The new network equipment will be deployed in three phases. The existing network supports 1,200
nodes. Which critical variable should the network architect consider when specifying the new applications to the
development team?
Whether the application should be data center-based or a cloud-based SDN solution
The nature of the SDN/Virtualization application and infrastructure
The ability for OpenFlow 1.3 to support IPv6 and multicast traffic
The interoperability of the legacy and the OpenFlow 1.3 compatible switches
The interoperability of the legacy and the OpenFlow 1.3 compatible switches
- There is a recurring connectivity failure between an SDN Controller and one of the switches. A Network
Operator is unable to isolate the issue. How should the operator resolve these issues?
Upgrade the SDN Controller to the latest software version
Upgrade the network switch to the latest firmware and OpenFlow protocol version
Identify the issue through the analytics component and follow a more specific troubleshooting process
Move the SDN Controller on a new server in a new location
Upgrade the network switch to the latest firmware and OpenFlow protocol version
- An Enterprise is upgrading a part of its current network of Ethernet switches to SDN with OpenFlow switches.
The Enterprise needs to consider the following:
o The legacy Ethernet part of the network uses VLAN 20
o The new SDN part of the network uses VLAN 10
This file is a study guide in preparation for the MEF-SNCP Exam intended for Globe Telecom employees.
Please do not share outside.
o An OpenFlow-hybrid switch connects the legacy Ethernet part and SDN part to L3 gateway using an IEEE
802.1Q trunk. Which OpenFlow rule should be specified in the hybrid switch to match and forward VLAN
20 traffic to the traditional Ethernet pipeline?
If VLAN ID = 20, forward to ANY port
If VLAN ID = 20, forward to CONTROLLER port
If VLAN ID = 20, forward to IN_PORT port
If VLAN ID = 20, forward to NORMAL port
If VLAN ID = 20, forward to NORMAL port
- A Service Provider offers data and voice services to its customers. The Service Provider offers a link with a
capacity of 10 Gbps between two OpenFlow switches. The Service Provider wants to limit the data traffic to 70%
of the link capacity and leave the remaining capacity for voice services. The network administrator created an
OpenFlow queue that was attached to the port and connected to the link. The link directed all data traffic (NOT
voice) to that queue. What is the proper configuration of the queue?
Minimum rate = 3 Gbps; Maximum rate = 3 Gbps
Minimum rate = 7 Gbps; Maximum rate = 7 Gbps
Minimum rate = 3 Gbps; Maximum rate = 10 Gbps
Minimum rate = 7 Gbps; Maximum rate = 10 Gbps
Minimum rate = 7 Gbps; Maximum rate = 7 Gbps
- A Service Provider offers a data plan to customers that contains the following SLAs: a guaranteed rate of 1
Mbps and a maximum rate of 2 Mbps. The Service Provider deploys OpenFlow switches in their network and
wants to implement the SLAs using OpenFlow meters. Customer traffic is subject to a meter band with 2 meters.
What is the proper configuration of the 2 meters in the meter band?
Meter 1: rate = 1 Mbps, type = DSCP remark; Meter 2: rate = 2 Mbps, type = drop
Meter 1: rate = 1 Mbps, type = drop; Meter 2: rate = 2 Mbps, type = drop
Meter 1: rate = 1 Mbps, type = DSCP remark; Meter 2: rate = 1.5 Mbps, type = DSCP remark
Meter 1: rate = 1 Mbps, type = drop; Meter 2: rate = 2 Mbps, type = DSCP remark
Meter 1: rate = 1 Mbps, type = DSCP remark; Meter 2: rate = 2 Mbps, type = drop
- Network operations wants to confirm that the SDN Controller to SDN Switch communication path is
functional. Which protocol should the operator use to verify latency and continuity?
UDP Connection
Hello Messages
TLS Sequencing
Echo Request/Reply
Echo Request/Reply
- In a mobile network, several base stations are attached to the core via a single mobile backhaul wireless link.
Power is available only at the remote end of the backhaul link. The installation of an SDN switch at the remote
end to connect the base stations via the backhaul link to the network core is the first step toward a dynamically
configurable network. Which approach allows the SDN controller located in the core to control the remote SDN
switch?
The SDN control connection is established in-band and isolated from the data traffic
The SDN switch at the remote location is equipped with a battery backup unit
The SDN control connection uses an unreliable transport protocol (such as UDP)
The SDN control connections are established to both master and slave SDN controller
The SDN control connection is established in-band and isolated from the data traffic
- The Service Provider is deploying this SDN topology with the following configuration:
• OpenFlow channel used to exchange OF messages between the controller and the OF switches is on a dedicated
network using the out-of-band OF switch interface
• The subnet address of this dedicated network is 192.168.1.0/24; controller IP = 192.168.1.100
• The connection to the SDN controller must be secured
After establishing the above connections and rebooting the switches, the OF switches failed to establish
connection with the SDN controller. The IT Administrator suspected that it is a connection URl configuration
problem in the OF switches. What should the IT administrator verify when troubleshooting this problem?
The connection URl configured in both OF switches is TLS:192.168.1.100:6653
The connection URl configured in the first OF switch is TCP:192.168.1.1:6653
The connection URl configured in both OF switches is TLS:192.168.1.1:6653
The connection URl configured in both OF switches is TCP:192.168.1.100:6653
The connection URl configured in both OF switches is TLS:192.168.1.100:6653
- The network engineer wants to design the network to be resilient and be able to continue OpenFlow Switch
forwarding even if communications to the SDN Controller is lost. Which SDN Switch Mode must be enabled?
Fail normal mode
Fail secure mode
Fail switch mode
Fail secure drop mode
Fail secure mode
- A client wants to create a level of network resilience that prevents dynamic SDN traffic sent from the
controller to continue in the Switch OpenFlow Pipeline processing if the switch loses connectivity to the SDN
Controller. The degraded operation will result in the switch continuing to operate in its native underlying switch
or router mode. Which configuration mode will provide this level of functionality?
Fail secure mode
Fail standalone mode
Fail normal mode
Fail secure drop mode
Fail standalone mode
- An SDN network is built using OpenFlow version 1.3 as the Southbound API. Both the master and slave SDN
Controller have experienced a catastrophic failure. The switches are configured in Fail-Secure mode. How will the
forwarding plane behave in this situation?
The SDN Switches will drop all traffic received through the active physical ports
The SDN Switches will only forward new flows through the active physical ports
The SDN Switches will forward all traffic through the active physical ports
The SDN Switches will forward already configured flows through the active physical ports
The SDN Switches will forward already configured flows through the active physical ports
- An Operator is trying to create 6,000 virtualized networks that are interconnected through a common Layer 2
closed user group. The Layer 2 networks must support both unicast and broadcast delivery. Because there is a 4K
limitation when using VLANs, which IP-based overlay can accomplish this task?
VXLAN
IPv6
IPSEC
MPLS
VXLAN
- An SDN application subscribes to Emergency Alert Systems for the locations where SDN Switches are present.
The application receives an earthquake alert. What should the SDN Controller do to mitigate connectivity loss to
customer-facing traffic?
Broadcast the traffic to all SDN Switches in the affected areas
Dispatch a technician to the unaffected area
Redirect the traffic away from the affected areas
Configure more ports on the SDN Switches in the affected areas
Redirect the traffic away from the affected areas
- A user is deploying an SDN solution to upgrade a decade-old legacy routed network. The user prefers to
deploy the SDN network in a mixed mode/hybrid fashion with some devices managed via OpenFlow and other
devices managed via NETCONF/YANG. Which SDN Controller should the user select?
OpenStack
OpenDaylight
Open Source Networking
Open Software Defined System
OpenDaylight
- A network is experiencing long delays in acknowledging communication between the network switches and
the SDN Controllers. The use of multiple protocols between the controllers and the switches is causing an
increase in latency. The SDN Controllers were originally Beacon but have been upgraded to Ryu since Beacon
failed to meet the network’s requirements. Which approach addresses this problem?
Roll back to the Beacon SDN Controller
Implement high availability functionality for all network elements
Fix the APIs for each of the applications on the network
Replace Ryu with two OpenDaylight controllers in active/active mode
Replace Ryu with two OpenDaylight controllers in active/active mode
- Several employees on the same floor report erratic network behavior. The SDN control channel to the switch
on that floor is NOT established. What is the first step the SDN engineer should do to troubleshoot the OpenFlow
connection?
Reboot the SDN Controller and wait for the problem to resolve automatically
Trigger a connection re-establishment from the SDN Controller
Make sure that the SDN Switch has the correct SDN Controller configured
Unplug all cables from the SDN Switch to avoid a security risk
Make sure that the SDN Switch has the correct SDN Controller configured
- The new “Aggregation 2” switch must to be added to handle the traffic growth. The entire network is
controlled through the SDN Controller. Which configuration must be performed to integrate the new Aggregation
2 switch into the SDN network?
Configure the flow tables in the new switch so that traffic is forwarded to the appropriate destination
Configure the activation of the spanning tree protocol because it will automatically set up connectivity
Configure the routing protocol parameters and neighboring nodes and next hops
Configure the SDN controller and the control connection parameters such as encryption, protocol, etc.
Configure the SDN controller and the control connection parameters such as encryption, protocol, etc.
- An organization has assigned the network architect to design an SDN network in a hybrid switch environment.
The network has the following requirements:
• The SDN solution should be OpenFlow 1.3 or later with an open source SDN controller solution
• There has to be encrypted route traffic information between the SDN controllers
What should the architect do to meet the network design requirements?
Replicate the TCAM information in the non-OpenFlow switches to the OpenFlow switches
Mandate that all applications use network overlays to populate the inter-switch links in the network
Recommend that all of the switches meet a tuple-parsing minimum in the packet header that is faster
than traditional non-SDN switches
Recommend the ODL Neutron SDN Controller, since it provides the most thorough addressing of the
requirements
Recommend the ODL Neutron SDN Controller, since it provides the most thorough addressing of the
requirements
- The Service Provider has deployed SD-WAN software in their network. After a controller upgrade, the system
administrator tried to deploy a white box branch device, which failed during the usual deployment procedures.
What could be causing the failure of this deployment?
The underlay network needs to be downgraded to the previous software version
The branch device software needs to be supported by the controller software
The controller and all the white box devices need to be rebooted
The white box device needs to be replaced with a new one
The branch device software needs to be supported by the controller software
- Network Operations wants to be notified whenever a new switch or device is added to the SDN Network.
What type of SDN application is needed?
Reactive application
Proactive application
RESTful application
Preemptive application
Reactive application
- An Operator is upgrading a legacy network to SDN. The upgrade should be transparent to the legacy
networking devices. What should the Operator do to meet this requirement?
Install an SDN Controller supporting OpenFlow and replace the networking devices with devices
supporting OpenFlow
Install a NETCONF Agent on the networking devices and install an SDN Controller supporting
NETCONF/YANG
Install an SDN Controller that can support the legacy southbound interfaces and install the relevant
applications
Install an OpenFlow Agent on the networking devices and install an SDN Controller supporting OpenFlow
Install an SDN Controller that can support the legacy southbound interfaces and install the relevant
applications
- A network company buys another network company. The engineers and architects must determine how to
merge the two networks. Both have an MPLS backbone with the presence of BGP route reflectors and use various
routing protocols in their networks such as IS-IS and OSPF. Both have a mixture of traditional equipment and SDN
equipment. For certain applications, they both use ODL. It is recommended to use an SDN architecture.
Which SDN solution should be used for the merge?
Replace the two local ODL controllers with a central ODL controller using Path Computation Element
Protocol (PCEP) and OpenStack
Create a single Network to Network Interface and use BGP
Update the VNF forwarding graph with a new virtual link
Replace the two local ODL controllers with a central ODL controller using BGP-LS and Path Computation
Element Protocol (PCEP)
Replace the two local ODL controllers with a central ODL controller using BGP-LS and Path Computation Element Protocol (PCEP)
- The CTO and management want the SDN applications introduced into production as soon as possible, even if
there is a risk that the hybrid SDN solution may not scale. The architect has the promises of all the different
vendors - network switch, SDN controller, and SDN applications - that the solution will work. None of those
promises are in writing. What is the most compelling argument for pausing to deploy a formal test lab for SDN
applications?
SDN gives greater management control to the network, so it is important to investigate all aspects of
that management prior to deployment.
Advocate for an agile framework so that any programming modifications can be swiftly modified in the
SDN applications.
As long as the vendors have promised interoperability verbally, what remains is to secure a written SLA
from each of the vendors.
SDN reduces operational expense of running the network, so additional resources can be added to apply
out-of-band management solutions.
SDN gives greater management control to the network, so it is important to investigate all aspects of
that management prior to deployment.
- A company’s network infrastructure has been upgraded to OpenFlow-based white box switches. The network
architect is selecting an open-source SDN controller. The architect has several options, but none fully support the
planned deployment. They all require some extensions. The goal of the deployment is to implement priority
treatment for the network traffic of the company’s CEO, who regularly visits branch offices located in many
locations around the world.
Based on these requirements, which features are most important for this deployment?
Secure north-bound interfaces and automatic conflict detection
Isolation of various tenants and wide-range of accounting and reporting options
Flexible QoS management and a unified network model
Support for multiple SDN control protocols and model-based extensibility
Flexible QoS management and a unified network model