exam2.docx

Exam: Software-Defined Networks (SDN) Question 1: Which of the following statements are true about SDNs (software-defined networks)? Select all that apply.\" Question 2: In an SDN-controlled network, the rules for forwarding packets can be computed based on which of the following? Select all tha...

Exam: Software-Defined Networks (SDN) Question 1: Which of the following statements are true about SDNs (software-defined networks)? Select all that apply.\" Question 2: In an SDN-controlled network, the rules for forwarding packets can be computed based on which of the following? Select all that apply. Question 3: Which of the following functions are typically associated with the control plane in a network? Select all that apply. Question 4: The following figure represents an overview of the SDN paradigm. Which component would go in box 1? D. Host Info Question 5: The following figure represents an overview of the SDN paradigm. Which component would go in box 2?  Question 6: The following figure represents an overview of the SDN paradigm. Which component would go in box 3? A diagram of a network controller Description automatically generated Question 7: The following figure represents an overview of the SDN paradigm. Which component would go in box 4?  Question 8: An IXP cannot offer peering without an SDX-enabled architecture. Question 9: Traffic engineering is an example application of an SDX-enabled architecture. Question 10: Within an SDX architecture, each AS can drop, forward, or modify its own traffic. Question 11: An AS participant needs to coordinate \"offline\" with other AS participants before advertising a path. Question 12: BGP is the default routing protocol, but it has limitations that make routing unreliable and sometimes difficult to manage. Which of the following statements are true about the BGP protocol? Select all that apply. Question 13: Choose which of the following statements are true about the P4 model and the P4 language. Select all that apply. Question 14: The figure below shows the landscape of the SDN architecture decomposed into layers. Match the missing components with their respective names. Which component would go in box 1? Question 15: The figure below shows the landscape of the SDN architecture decomposed into layers. Match the missing components with their respective names. Which component would go in box 2? Question 16: The figure below shows the landscape of the SDN architecture decomposed into layers. Match the missing components with their respective names. Which component would go in box 3?  Question 17: Choose which of the following statements are true about OpenFlow. Select all that apply. Question 18: What is possible for participant ASes using an SDX architecture? Select all that apply. Question 19: BGP Blackholing is a technique used to safeguard against which event? Question 20: Under which attack is traffic intercepted by a malicious actor and manipulated before it reaches the receiving host? Question 21: What property of secure communication is violated when a message is intercepted, but not changed, by an unintended third party? Question 22: Which property of secure communication is primarily compromised when an attacker successfully carries out a Denial of Service (DoS) attack? Question 23: Assume that your host interacts with an HTTP server. You want to detect if the HTTP server is part of a Fast Flux Service Network (FFSN). Which of the following will strengthen the belief that DNS abuse is taking place via FFSN? Select all that apply. Question 24: Consider the diagram below. The attacker uses a router to announce the prefix 10.10.0.0/16 that belongs to AS1, with a new origin AS4, pretending that the prefix belongs to AS4. This new announcement causes a conflict of origin for the ASes that receive it (Multiple Origin AS or MOAS). As a result of the new announcement, AS2, AS3, and AS5 receive the false advertisement and they compare it with the previous entries in their RIB. Which ASes will believe the false advertisement? Select all that apply. Question 25: Consider the figure below, where we see an attack scenario where a legitimate path is hijacked. The attacker manipulates received updates before propagating them to neighbors. AS1 advertises the prefix 10.10.0.0/16. AS2 and AS3 legitimately receive and propagate the path for the prefix. At AS4, the attacker compromises the update for the path by changing it to 4.1, and propagates it to the neighbors AS3, AS2, and AS5. Therefore, it claims that it has a direct link to AS1. Which ASes will believe this false advertisement? Select all that apply.  Question 26: In a prefix hijacking scenario, how can the victim AS use Prefix De-aggregation to defend against the attack? Question 27: What method does Mitigation with Multiple Origin AS use to ensure that BGP hijacking is thwarted? Question 28: Consider the BGP Blackholing technique in the image below. The provider of the victim AS1 is also the blackholing provider. When the victim AS2 detects that it is under a DDoS attack, what will AS2 do? Question 29: Consider the BGP Blackholing technique in an IXP infrastructure. If AS2, which is a member of an IXP infrastructure, is under attack, which of the following events will happen as part of the IXP-based BGP blackholing?  Question 30: Which DNS censorship method discards all network traffic going to a set of specific IP addresses? Question 31: The Great Firewall of China uses DNS poisoning to block access to certain websites. Does this process lead to overblocking? Question 32: Which DNS censorship method involves a proxy examining and discarding objectionable content? Question 33: Which TCP flag does the Great Firewall of China use to block connections? Question 34: Consider the Augur system, which uses a strategy based on IP ID to detect whether blocking is occurring. The scenario below shows all the steps that the measurement machine takes. The IP ID is initially 6, and the final IP ID is 8. What does the measurement machine detect? Question 35: Consider three different kinds of multimedia applications: (1) streaming video, (2) a photo gallery that displays a new image every second, and (3) an audio player. Order the applications from least to greatest by their bit rate requirement. Question 36: What is a key feature of streaming stored video in multimedia applications? Question 37: In the context of Voice over IP (VoIP) applications, which of the following statements best describes the concept of \"effective packet loss\"? Question 38: Which quality-of-service metric for VoIP is impacted by the time it takes to encode the audio? Question 39: Which quality-of-service metric for VoIP is improved by using an appropriately sized buffer at the end system? Question 40: The TCP receive buffer and the media player\'s client buffer are the same thing. Question 41: Consider the prescribed methods for managing packet loss with VoIP. Which method increases bandwidth consumption? Question 42: Consider the prescribed methods for managing packet loss with VoIP. Which method guesses the lost packet? Question 43: Which is the correct method to calculate the buffer-filling rate in a video buffer? Question 44: Where is the bottleneck that causes packet loss and increased latency? Question 45: Which of the following statements describes the trend of the evolution of Internet topology? Question 46: An end-user directly interacts with the authoritative DNS server. True or false? Question 47: Can CDN cluster selection be influenced by factors other than geographical proximity and server health? Question 48: Which layer of the Internet stack does the DNS protocol belong to? Question 49: Consider the iterative DNS query. Also assume all caches are empty. Select the DNS servers in the order that they are used to complete the DNS resolution for a domain. Question 50: Which of the following practices allows for a single IP address to be allocated to different devices across multiple locations?