CS 6250 Quiz 2 (All Quizzes) Latest Update | Verified Questions and Correct Answers | Complete

Exam

CS 6250 Quiz 2 (All Quizzes) Latest Update | Verified Questions and Correct Answers | Complete Study Guide – Georgia Institute of Technology 2026/202 ... 7 | GRADED A+ | 100 out of 100 Questions: What are 2 reasons computer networks are complex and difficult to manage that led to the development of SDN? Answer 1. Diversity of network equipment 2. Proprietary technology required for equipment Questions: Why would equipment diversity cause complexity when managing a network? Answer Different software must be used for different protocols (7) Questions: Why do proprietary technologies cause complexity when managing networks? Answer Some equipment (router, switch, etc.) run on closed/proprietary software Configuration interfaces vary as a result. This causes issues for managing devices centrally. (7) Questions: What is the simple idea of SDN that helps make networks more manageable? Answer Separate tasks into control plane and data plane. (7) Questions: What are the 3 phases of history of SDN? Answer 1. Active networks 2. control plane and data plane separation 3. OpenFlow API and network operating systems (7) Questions: What led to the growth of active networks, and what is their goal? Answer 1. the tediousness of standardizing new protocols 2. goal is to open up network control with an API that exposes resources and supports customization of functionalities for subsets of packets passing through network nodes (7) Questions: Why do active networks conflict with idea of E2E? Answer They require customization at network nodes (not simplicity at network core) (7) Questions: What were the two types of programming models in active networking? How are thy different? Answer 1. Capsule model - carries in band data packets - most used in relation to active networking - code distribution ACROSS networks - data plane 2. Programmable router/switch model - out of band mechanisms - decision-making a job for the NETWORK OPERATOR - Difference is where the code to execute at the nodes was carried (7) Questions: What are 4 tech developments that encouraged active networking? Answer 1. reduction in computation cost (more processing can take place in the network) 2. advancement in programming languages 3. advancement in rapid code compilation and formal methods 4. funding agencies promoted interoperability among projects - necessary because there were no short-term use cases (7) Questions: What are 4 problems that encouraged active networking? Answer 1. developing network services took a long time 2. third party interests to dynamically meeting needs of app and network conditions 3. researches needed a network for large-scale experiments 4. disadvantage of diverse models and vendors meant a desire for unified control over middleboxes (7) Questions: What are 3 contributions of SDN? Answer 1. programmable functions in network = lower barrier to innovation 2. network virtualization and ability to demultiplex based on packet headers 3. vision of unified architecture for middlebox orchestration (7) Questions: Which plane are active networks associated with? Answer Data plane (7) Questions: What plane do programmable functions in active networks focus on increasing programmability, and why? Answer - Data plane - isolate experimental traffic from normal traffic (7) Questions: What were some downfalls of active networking? Answer - it was too ambitions - didn't emphasize performance and security - it didn't solve any short term problems - end users need to be ale to write in java (7) Questions: Did active network do anything for performance? Security? Answer No (7) Questions: What challenge did control and data plane separation tackle? Answer Challenging how existing routers and switches tightly integrated the data and control plane (7) Questions: What were 4 tech developments that paved the way for control and data plane separation? Answer 1. packet forwarding (data plane) was implemented in hardware (separate from control plane) 2. ISPs couldn't meet increasing demands for greater reliability and new services b/c of increasing scope and size 3. servers have much more memory and processing resources - routing decisions could be done on one server for one ISP network 4. open-source routing lowers barrier to creating prototypes of centralized routing controllers (7) Questions: How did higher link speeds in backbone networks encourage control and data plane separation? Answer packet forwarding implemented in hardware, separate from control plane (7) Questions: What 2 innovations led to the control and data plane separation? Answer 1. open interface between control and data plane 2. logically centralized control of network(7) Was the network centrally controlled logically, physically, or both under control and data plane separation? Answer LOGICALLY centrally controlled(7) What are 3 ways control plane and data plane separation differed form active networks? Answer 1. Spurred innovation for network ADMINS instead of users 2. emphasized programmability in CONTROL domain instead of data domain 3. worked towards NETWORK-WIDE visibility and control rather than device level configurations(7) Was visibility and control at network level or device level for active networks? Control/data plane separation? Device level Network level (7) Was programmability in control domain or data domain for active networks? Control/data plane separation? Data domain control domain (7) Was innovation for network admins or users for active networks? Control/data plane separation? Users Admins (7) What are 5 use cases for control plane/data plane? 1. path selection based on network traffic load 2. minimized disruptions during planned routing changes 3. redirecting or dropping suspected attack traffic 4. allow customer networks more control over network flow 5. offer value added services for virtual private network customers (7) Were control plane and data plane separation efforts focused on managing routing WITHIN ONE ISP? No some wanted to enable flexible route control across many ASes (7) What 2 concepts resulted from control and data plane separation? 1. LOGICALLY centralized control w/ open interface to data plane 2. DISTRiBUTED state management (7) Was control plane/data plane separation logically distributed? No logically CENTRALIZED (7) Was control plane/data plane state management distributed or centralized? Distributed (7) Why was OpenFlow built on existing hardware? What was the weakness of this? Enabled immediate deployment Less flexibility (7) How does an openflow switch work? Switch has TABLE OF PACKET HANDLING RULES each rule has a pattern, list of actions, set of counters, and priority when packet is received, the switch: - determines highest priority matching rule - performs action - increments counter (7) What happens when an openflow switch receives a packet? - determines highest priority matching rule - performs action - increments counter (7) Which SDN tech was adopted in the industry: active networks, control/data plane separation, Openflow? Openflow (7) What are 3 tech developments that encouraged openflow? 1. programmers could control some forwarding behavior (b/c of switch chipset vendors) 2. companies could build switches without designing their own DATA PLANE 3. early versions of openflow were built on tech that switches ALREADY SUPPORTED - just a firm upgrade (7) Were early versions of openflow built from the ground up? No, built on tech that switches already supported (7) Was it difficult to integrate openflow? Why? No, built on already supported tech (7) What were 3 use cases for openflow? 1. large scale experiments on network 2. managing traffic at large scales in data-center networks 3. investing in programmers to write control programs, and less in proprietary switches that couldn't support new features (7) Did openflow prevent small players from being competitve? Why No, became more competitive b/c they could just focus on writing control programs instead of proprietary switches (7) What are 3 key effects of openflow? 1. GENERALIZATION of network devices and functions 2. Vision of NETWORK OPERATING SYSTEM 3. DISTRIBUTE STATE MANAGEMENT techniques (7) What does the control plane do? Logic that controls forwarding behavior of routers such as ROUTING PROTOCOLS and NETWORK MIDDLEBOX configurations DICTATES forwarding behavior (7) What does the data plane do? PERFORMS actual forwarding as dictated by control plane IP FORWARDING and LAYER 2 SWITCHING (7) What are 2 reasons to separate control and data plane? 1. independent evolution and development of both planes - ex. routing algorithms can improve WITHOUT AFFECTING EXISTING ROUTERS 2. Control from HIGH LEVEL software program - SDN uses software to COMPUTE forwarding tables - software to CONTROL router's behavior - DEBUGGING IS EASIER (7) What are 4 areas the separation of control/data plane helps? 1. Data centers - network management is easier 2. routing - SDN makes it easier to update state - more control over path selection 3. enterprise networks - SDN improves security applications - drop traffic at strategic locations 4. research networks - research can coexist w/ production networks (7) what are 2 important functions of network layer? 1. forwarding - determine which output link a packet should be sent to using forwarding table - LOCAL function implemented in HARDWARE - data plane - nanoseconds 2. determines path from sender to receiver across the network (usually with routing algorithms)

CS 6250 Quiz 2 (All Quizzes) Latest Update | Verified Questions and Correct Answers | Complete

Exam

Continue Reading This Document

Available in 12 Bundle

Reviews 0

Exam Details

Specifications

Seller Details

Recommended Documents

CS 6250 Quiz 8 Exam guide...

CS 6250 Quiz 4 Exam Prep...

CS 6250 Quiz 1 & Quiz 2 (...

Agile Safe 5.1 SPC Test-w...

AZ-104 Renewal Exam Quest...

What Students Are Saying About Us

Create Your Free Account

Welcome Back