CS 6250 EXAM 2 STUDY GUIDE: MODULES 7 AND 8 UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

CS 6250 EXAM 2 STUDY GUIDE: MODULES 7 AND 8
UPDATED ACTUAL QUESTIONS AND CORRECT
ANSWERS

Question:
1. Why are traditional networks hard to manage, in the view this lesson presents?
• A. The diversity of devices (routers, switches, middleboxes) and the proprietary, vendor-specific control
software running on each makes consistent network-wide policy hard to express and verify.
• B. Modern devices are too slow at line rate, so operators must continually replace hardware to keep up.
• C. IPv6 transition fundamentally broke the management plane that worked under IPv4.
• D. Open-source software dominates the data plane and lacks the maturity of vendor-shipped systems.
Answer:
A

Question:
2. [T/F] In traditional networks, the control logic and the packet-forwarding logic are tightly integrated
inside the same physical box.
Answer:
True

Question:
3. The history of SDN is often described in three phases. Which list is correct in chronological order?
• A. ARPANET; ATM; MPLS.
• B. Active networks; control/data plane separation; OpenFlow and network operating systems.
• C. Active networks; MPLS; P4 hardware programmability.
• D. OpenFlow; ONOS; SD-WAN deployment.
Answer:
B

Question:
4. [T/F] The conceptual separation of the control plane from the data plane predates OpenFlow by several
years.
Answer:
True

Question:
5. The lesson argues that separating control and data planes enables several benefits at once. Which one is
BEST captured by 'a logically centralized view of the network'?
• A. Forwarding decisions pushed to end hosts.
• B. Each device runs its own routing algorithm independently.
• C. The controller has the whole topology in one place and can compute consistent policies.
• D. The data plane gains write access to global routing tables.
Answer:
C

, Question:
6. In a traditional network, changing routing or security policy across many devices requires per-device
CLI commands. In SDN, the same change is expressed once at the controller. Beyond saving keystrokes,
which OPERATIONAL property does this centralization enable?
• A. Routers no longer need a control plane.
• B. Hardware-level encryption is automatic.
• C. Controller consulted per packet.
• D. Network config becomes centralized software-managed state (Git, CI, rollback).
Answer:
D

Question:
7. Consider an SDN network — where does routing computation occur?
• A. On a logically centralized controller.
• B. Inside each switch.
• C. On end hosts.
• D. At IXP route servers.
Answer:
A

Question:
8. Consider an SDN network where the controller runs remotely. Which architectural property enables
this?
• A. Data plane includes built-in tunnel.
• B. Control plane is software and physically decoupled; can run anywhere reachable.
• C. Routers run controller code locally.
• D. OpenFlow requires co-location.
Answer:
B

Question:
9. [T/F] In traditional networks, separating data plane and control plane conceptually existed — but they
ran inside the same box.
Answer:
True

Question:
10. In the SDN architecture figure, the infrastructure layer is responsible for which function?
• A. Acting as northbound API.
• B. Computing forwarding rules.
• C. Hosting network-control applications.
• D. Forwarding traffic according to controller-installed rules.
Answer:
D