Correct Answer: A

flush()

Pushes buffered data out the Stream; this is NOT guranteed to flush all data, multiple flush() calls may be

required, until needFlush() returns false.

Reference: org.openflow.io, Interface OFMessageOutStream

Correct Answer: D

OpenFlow instance connection interruption mode

You can set the type of behavior when the switch loses connection with the controller.

OpenFlow instance connection interruption mode

fail-secure

If the switch loses connection with all of the controllers, packets and messages destined to the current

controller are dropped. Flows continue to expire according to their time-outs.

Default: fail-secure

Reference: HP OpenFlow Switches

(page 21)

http://h20628.www2.hp.com/km-ext/kmcsdirect/emr_na-c03512348-4.pdf

Correct Answer: D

The Topology service is used to create a network graph and compute the shortest path between two hosts.

Note: Mininet is a network emulator that can create and emulate an entire OpenFlow network locally on

your PC.

Incorrect:

Not C: No need to analyze packages.

Wireshark is a free and open-source packet analyzer. It is used for network troubleshooting, analysis,

software and communications protocol development, and education.

Reference: HP VAN SDN Controller Administrator Guide

Correct Answer: A

Note:

idle_timeout - Number of idle seconds before the flow entry is removed. Defaults to no idle timeout.

priority - When using non-exact (wildcarded) matches, this specifies the priority for overlapping matches.

Higher values are higher priority. Not important for exact or non-overlapping entries.

actions - A list of actions to apply

. output: if no group action is specified, forward the packet on the port specified by the output action

Correct Answer: D

Node Manager

Operation:

Learns and maintains end-host locations in the network. Uses information received from network devices

to maintain the ARP table and end host data.

Uses the Topology Service to determine if a port receiving a packet is an edge port or not.

Learns and maintains end nodes in the controller domain, and associates end nodes with edge ports.

Builds an ARP cache with MAC-IP translations of end hosts.

Maintains ARPs on a per-VID basis.

Provides the edge port details for end hosts.

Reference: HP VAN SDN Controller Administrator Guide

Correct Answer: D

PLUMgrid's proprietary controller is designed to maintain control of its network virtualization solution and is not targeted at controlling external elements today. Like other network virtualization-focused controllers, it provides RESTful APIs in the form of proprietary northbound interfaces.

Reference: SDN Controller Wars 2.0 ON.LAB and Juniper Re-Ignite the Open-Source Battleground. Part 1 of 2 http://www.sdncentral.com/market/controller-onlab-juniper-open-source-sdn-battleground- part1/2013/12/

Correct Answer: B

OpenFlow version 1.3 is the latest version of OpenFlow that has support from switch vendors. It is significantly different from OpenFlow version 1.0 (which was the previous version several vendors supported). Among others, the main features added since then are:

1.1: Support for MPLS, Q-in-Q, VLANs, multipath, multiple tables, logical ports 1.2: Support for extensible headers (in match, packet_in, set_field), IPv6 1.3: Support for tunneling, per-flow traffic meters, Provider Backbone Bridging

Reference: OpenFlow version 1.3 tutorial

Correct Answer: BD

D_ The SDN controller enforces jar-signing validation by default. For an experimental/development environment where unsigned applications need to be deployed, jar- signing validation can be turned off altogether:

Stop the SDN controller: sudo service sdnc stop

2.

Modify the /opt/sdn/virgo/bin/dmk.sh script to include the line "-Dsdn.signedJar=none \"

3.

Start the SDN controller:

sudo service sdnc start

B: Adding Certificates to Jar-Signing Truststore

To deploy other signed applications onto the controller, use the Java keytool to import the public certificate

that was used to sign the application jars into the controller jar-signing truststore (/opt/sdn/admin/

sdnjar_trust.jks):

keytool -importcert -keystore /opt/sdn/admin/sdnjar_trust.jks -file signed_app.cer -alias mysignedcert

The controller needs to be restarted for the new truststore to take effect.

Reference: HP VAN SDN Controller Administrator Guide

Correct Answer: C

In Aggregation mode, all VLANs in the switch are part of an OpenFlow instance. When Aggregation is configured, there is only OpenFlow traffic, no production traffic.

Reference: HP OpenFlow 1.3 Administrator Guide, Wired Switches K/KA/KB/WB 15.15

Correct Answer: A

LLDP is used to discover direct links between switches and BDDP is used to discover the switches in the same broadcast domain.

Note: Using a link-discovery module, the controller generates both LLDP and broadcast packets (referred to as BDDPs) and sends them to all neighboring switches on a regular basis.

Reference: OpenFlow Controller