CS4220: Computer Networks - Final Exam

What is the temporary storage called in which recently contacted MAC addresses are stored? ARP cache Proxy ARP RARP cache ARP file

ARP cache

What is the name of the relationship between two OSPF devices that are connected together and exchange link-state information? Group of answer choices Peering Adjacency Autonomous systems Attachments

Adjacency

Which of the following applies to a client-server network? (Choose two.) Administration of client/server is centralized using a dedicated administration server. The users must login to gain access using credentials administered on the server. Client-server networks are primarily used for decentralized management. Client/server networks are not commonly used by businesses.

Administration of client/server is centralized using a dedicated administration server. The users must login to gain access using credentials administered on the server.

A broadcast may cause a network slow-down. True or False? Justify your answer in 3 sentences. hint - start by defining broadcast transmissions and go from there.

Broadcast transmissions hit all devices: Data is sent to everyone, not just the intended. Processing and examination by all devices: Every device on the network has to pause amd process and examine the broadcasted data. Network congestion and slow-downs; Excessive broadcasts can clog up the network, using bandwidth and resources. Negative impact on overall network performance: In larger networks, this can lead to a slowdown, affecting performance. ( I didn't know how to do this in 3 sentences I am sorry).

One of the key features in the Transport layer is error control. Select each option that is true about error control. Group of answer choicesChecks for errors in the data receivedOften completed using checksumsFormat-preserving encryptionEnsures data integrity

Checks for errors in the data received Often completed using checksums Ensures data integrity

If a PC on an Ethernet network attempts to communicate with a host on a different subnet, what destination IP address and destination MAC address will be placed in the packet/frame header sent by the PC? Group of answer choices Dest. IP: IP address of remote host. Dest. MAC: MAC address of local PC. Dest. IP: IP address of remote host. Dest. MAC: MAC address of default gateway. Dest. IP: IP address of default gateway. Dest. MAC: MAC address of default gateway. Dest. IP: IP address of remote host. Dest. MAC: MAC address of remote host.

Dest. IP: IP address of default gateway. Dest. MAC: MAC address of default gateway.

A router first looks for what piece of information before making a forwarding decision? Group of answer choices Source IP address in a packet Destination MAC address in a frame Destination IP address in a packet Destination Port number in a segment

Destination IP address in a packet

What is the purpose of ECE and CWR in the TCP header? ECE signals the TCP receiver to slow down, while CWR signals the TCP sender to stop sending packets. ECE signals the TCP receiver to slow down, while CWR signals the TCP sender to slow down as well. ECE signals the TCP sender to speed up, while CWR signals the TCP receiver to slow down ECE signals the TCP sender to slow down, while CWR signals the TCP receiver to stop sending packets.

ECE signals the TCP receiver to slow down, while CWR signals the TCP sender to slow down as well.

All of the following network issues need to be addressed for quality of service, except one. Which of the below options is not a primary consideration when analyzing QoS?

Ensuring encryption is applied to data at rest

You recently designed a network. Given what you learned in that activity, what devices and services did you find as critical to have included in your network design? Provide three facts about network design that you discovered.

I think in between class and learning some basic fundamentals at my internship over the past two semesters, I would focus on these 3 aspects: Firewall to enhance security Firewalls monitor and control network traffic, and they are acting as a barrier to unauthorized access and threats. Segmentation improvement Network segmentation enhances security and performance - they are dividing it into manageable segments. Redundancy helps with reliability Redundant components, like backup routers or switches - they increase network reliability and also minimize downtime.

What networking device often uses data signatures to identify suspicious traffic to help stop attacks? Group of answer choicesProxy ServerWireless LAN ControllerMedia ConverterIDS

IDS (Intrusion Detection System)

For IPv6, which of the following can be used to enhance security while avoiding deploying a DHCP server?

IPSec

Select each option considered a network hardening best practice? Choose 3. Group of answer choices Implement role-based access Apply patches and updates Disable unneeded services Use of default passwords

Implement role-based access Apply patches and updates Disable unneeded services

Which of the following statements accurately describe wireless network modes? Infrastructure MIMO MANET Ad hoc WAN

Infrastructure

What are the three principles of cybersecurity? Select 3. Integrity Availability Non-repudiation Confidentiality Encryption Authorization

Integrity Availability Confidentiality

An administrator suspects an employee is bypassing policy to visit unauthorized websites during work hours. Besides consulting a proxy service, which of the following would reveal websites in the recent DNS cache? NSlookup /search Ipconfig /displaydns Ipconfig /review NSlookup /mx

Ipconfig /displaydns

What is the purpose of RTP in VoIP? Group of answer choices It manages the dial plan. It connects the VoIP phone to an analog phone. It works with a PBX. It carries voice and video.

It carries voice and video.

Which term describes the difference in latency between packet flow from one client to another? Group of answer choicesRound-trip timePacket lossJitterThroughput

Jitter

Match the OSI Layer with the definition. Physical Data Link Network Transport Session Presentation Application

Physical Responsible for the physical transmission of data over the network. Data Link Provides reliable transmission of data over the physical layer by defining protocols for error detection and correction, flow control, and framing. Also has a Media Access Control (MAC) sublayer for addressing devices on the network using the MAC address. Network Provides logical addressing and routing of data packets between different networks. Transport Maintains connections between applications on different devices and defines protocols for breaking data into smaller segments, ensuring reliable delivery. Session Maintains connections between applications on different devices. Presentation Responsible for data representation and encryption. Defines protocols for converting data into a format that can be understood by the application, such as character encoding and compression. Application Provides services to end-user applications, such as email, web browsing, and file transfer. Also responsible for end-to-end delivery of data between applications on different devices and defines protocols for breaking data into smaller segments, ensuring reliable delivery.

Which of the following are true regarding UDP? Flow control Retransmission upon receipt of a bad segment Provide an interface to the IP protocol with the added feature of demultiplexing multiple processes using the ports Optional end-to-end error detection

Provide an interface to the IP protocol with the added feature of demultiplexing multiple processes using the ports Optional end-to-end error detection

What device, configured in the client web browser, can cache web content and also be a URL filter? Group of answer choices Media Converter Wireless LAN Controller IDS Proxy Server

Proxy Server

Fill in the blank to complete the sentence correctly. The _________ address is another name for a MAC address. logical autoconfigured physical abstract

physical

This question is worth extra credit. If you do not opt to answer this question, it will have no impact on your grade. If you make an attempt, the extra points will be added to the score you earned on your final. Partial responses will be awarded partial credit. 1. What is a zero-day attack and why are they particularly effective? //1 pts 2. List and describe the three-way handshake performed in TCP. What does each step of the handshake do? Be specific. //1 pts 3. Describe DNS spoofing. // 1 pt 5. Which IEEE working group standard governs Wireless? //1 pt 6. What did you memorize, that was not asked on the exam, and you would like to share that knowledge for 1 pts of extra credit?

1. It's an attack on a vulnerability that hasn't previously been known or used. They are normally quite effective because there's no prevention, mitigation or responses created for the vulnerability at that time. 2. 1 syn: client initiates connection, sends an initial sequence number. 2 syn-ack: Server responds to the syn, acknowledges initial sequence number of client, sends server's initial sequence number. 3 ack: Asknowledges the server's sequence number, signals ready to transer data and establishes full connection. 3. A form of attack that uses where an actor uses DNS caching to redirect users to fake websites or monitor their connection. 5. ? I think 4 was skipped. IEEE 802.11. 6. Maybe parts of a frame/framing. Or knowing acronyms and what they stand for.

Answer the following questions: 1. What is the host name of your computer? //1 pt 2. What is your MAC address? //1 pt 3. Trace the route a packet would take to arrive at IP 8.8.8.8 // 0 pts 4. What does column five of the results indicate? // 1 pt 5. What is the name associated with the IP 8.8.8.8? //1pt 6. What is 8.8.8.8?//1 pt. EC (the answer is not 'an IP address') 7. Why is 8.8.8.8 used?//1 pt. EC

1. Philbert 2. 60-45-CB-6D-A2-4F 3. Tracing route to dns.google [8.8.8.8]over a maximum of 30 hops: 1 <1 ms <1 ms <1 ms 192.168.227.12 8 ms 6 ms 6 ms 1.kellin.net.5.57.198.in-addr.arpa [198.57.5.1]3 * * * Request timed out.4 * * * Request timed out.5 * * * Request timed out.6 52 ms 51 ms 51 ms 192.178.86.617 31 ms 31 ms 36 ms 142.251.51.2218 37 ms 38 ms 33 ms dns.google [8.8.8.8] Trace complete. 4. Column 5 shows the name associated with the IP5. dns.google is [8.8.8.8] 6. 8.8.8.8 is a public DNS server operated by Google. 7. Used for DNS queries commonly.

What is the network address for APIPA? 169.254.0.0/16 172.16.0.0/16 192.168.0.0/24 10.0.0.0/8

169.254.0.0/16

A source IP Socket address of 192.168.1.10:53 has been detected. What kind of information is being returned to the destination? Ransomware alert An Fully Qualified Domain Name/IP match Spine and Leaf system info A VLAN number

An Fully Qualified Domain Name/IP match

The acronym TCP/IP stands for Transmission Controller Protocol/Intercommunication Protocol. True or False?

False

A multicast is characterized by which of the following? Group of answer choices It uses Class C addressing. It sends transmissions to all of its neighbors. None of these answers are correct. It is used when messages are sent to a specific group of networking devices.

False -Got incorrect

Which of the following is one of the main services provided by sliding windows?

Flow control

What is the name of a network machine deployed to lure attackers away from the real servers and provide tracking information? Sticky MAC Honey pot Sugar trap Port Mirroring

Honey pot

One reason this device is mostly replaced by switches is that it sends all traffic out all ports, thus compromising local security on the affected wires. Which device is this? Group of answer choices Patch Panel Hub Bridge MAU

Hub

Which of the following option are true about multiplexing? Select two. Sends email over connections and reports back the delivery status and any errors Multiple demarcation points are established in a building. Multiple high-speed data streams combined into a single, higher-speed stream ​ Sharing several conversations over connections, virtual circuits, and physical links plays a role in several layers of the network architecture

Multiple high-speed data streams combined into a single, higher-speed stream ​ Sharing several conversations over connections, virtual circuits, and physical links plays a role in several layers of the network architecture

Which of the following statements are true about Network Address Translation (NAT)? Select all that apply. Group of answer choicesNAT allows each computer within a customer network to have a unique IP address.NAT assigns a unique IP address to each home or business for Internet traffic.NAT is used to translate a unique internal IP address to a shared public IP address just before a packet exits the customer network and goes to the ISP.Packets containing private IP addresses can appear on the Internet itself.NAT makes use of three ranges of IP addresses that have been declared as public.

NAT is used to translate a unique internal IP address to a shared public IP address just before a packet exits the customer network and goes to the ISP. Packets containing private IP addresses can appear on the Internet itself. NAT makes use of three ranges of IP addresses that have been declared as public.

Which of the following is a difference between POP3 and IMAP? POP3 stores emails on the local device, while IMAP stores emails on a remote server. POP3 always requires SSL encryption, while IMAP does not support encryption. POP3 is a newer email protocol than IMAP. POP3 allows for synchronization of email across multiple devices, while IMAP does not support synchronization.

POP3 stores emails on the local device, while IMAP stores emails on a remote server.

A site survey has revealed the following potential vulnerabilities to network security and performance at a retail location that in a strip mall. The store is 35 wide by 100 deep. There are adjacent businesses within 60 feet that are using channels 6 and 11. There is a public court for eating located directly across the street. Employees are allowed to BYOD, but there is no desire to create a guest network. What recommendation(s) should be made for this situation? Hint: Two recommendations are suggested. Each suggestion should explain why it is recommended, how it will positively/negatively impact the network, and what the benefit is.

Recommendation 1: Implement Wireless Channel Planning Why it's recommended: Neighboring businesses are using channels 6 and 11, which could lead to interference. How it will positively impact the network: Channel planning involves selecting a non-overlapping channel (i.e. channel 1) to minimize interference, improving overall network performance. What the benefit is: The benefit is a more stable and efficient wireless network, reducing the chances of signal overlap and congestion, providing better connectivity for both employees and customers. Recommendation 2: Enable Wireless Security Protocols, Especially for BYOD Devices Why it's recommended: Employees are allowed to BYOD, creating potential security risks. How it will positively impact the network: Enabling robust wireless security protocols like WPA3 adds an extra layer of protection, preventing unauthorized access and securing sensitive data. What the benefit is: The benefit is enhanced network security, reducing the risk of data breaches or unauthorized access. This is crucial in a retail setting where customer trust and data protection are paramount.

Which policy uses the assignment of rights and permissions based on a job title or a common set of restrictions? Separation of duties Zero Trust Posture assessment Role-based access

Role-based access

To avoid using Telnet, what protocol allows to secure access to remote systems for management purposes? SSH SNMPv1 IMAP IPSec

SSH

You have just opened the box for a new WAP to be part of your guest network. Which of the following are recommended as a minimum set of best practices? Select an encryption protocol that is current and not easily broken Upgrade the firmware Enable the default SSID broadcast Isolate the guest network from the corporate WLAN Change the default administrative SSID and password

Select an encryption protocol that is current and not easily broken Upgrade the firmware Isolate the guest network from the corporate WLAN Change the default administrative SSID and password

Given the Class C network address 192.168.1.0/26 create three subnets that meet the following specifications: Subnet 1 supports 17 hosts Subnet 2 supports 14 hosts Subnet 3 supports 12 hosts Subnet 4 supports the maximum number of hosts possible //not worth points What is the network ID, usable range of IP addresses, and the broadcast of each of the three subnets created? Example of how you could respond to this question: Subnet 1:Network IDUsable Range of IP addressesBroadcast address Subnet 2:Network IDUsable Range of IP addressesBroadcast address Subnet 3:Network IDUsable Range of IP addressesBroadcast address Subnet 4:Network IDUsable Range of IP addressesBroadcast address

Steps Class C network address 192.168.1.0/26. Subnet mask is /26, which means there's 64 IP addresses in each subnet. Find # of subnets required for each situation. Assign subnets consecutively based on the number of hosts needed in each subnet. Calculate network ID, usable range, and broadcast address for each subnet. Each situation answers: Subnet 1: Network ID: 192.168.1.0 Usable Range of IP addresses: 192.168.1.1 to 192.168.1.30 Broadcast address: 192.168.1.31 Subnet 2: Network ID: 192.168.1.32 Usable Range of IP addresses: 192.168.1.33 to 192.168.1.46 Broadcast address: 192.168.1.47 Subnet 3: Network ID: 192.168.1.48 Usable Range of IP addresses: 192.168.1.49 to 192.168.1.60 Broadcast address: 192.168.1.63 Subnet 4 (Maximum hosts possible): Network ID: 192.168.1.64 Usable Range of IP addresses: 192.168.1.65 to 192.168.1.126 Broadcast address: 192.168.1.127

DHCP configurations can exclude IP addresses from the scope of available addresses for the use of statically configured devices. What type of network device could it be useful to exclude from a DHCP configuration? Group of answer choices Sales department laptop Storage server BYOD employee smartphone Thin client in the marketing department

Storage server

Identify the information associated with each protocol and port listed by matching. TCP/ICP FTP -- Is this supposed to be RDP? Port 21 isn't an option... Simple Mail Transfer Protocol Address Resolution Protocol Used to remotely access and manage network devices and systems securely. - Port 22 - Port 25 - Used to map a device's IP address to its physical MAC address on a network. - HTTP - Port 3389 - SSH - The foundation protocol of the internet and most computer networks, responsible for reliably transmitting data packets between devices and across intranetworks.

TCP/ICP- The foundation protocol of the internet and most computer networks, responsible for reliably transmitting data packets between devices and across intranetworks. FTP Port 3389 Simple Mail Transfer Protocol - Port 25 Port 80 - HTTP Address Resolution Protocol - - Used to map a device's IP address to its physical MAC address on a network. Used to remotely access and manage network devices and systems securely. - SSH

Simple Mail Transfer Protocol (SMTP) sends email over connections and reports back the delivery status and any errors. True or False?

True

Site surveys are recommended for large wireless networks but are typically not required or even necessary for small networks with a limited number of access points. True or False?

True

The Bandwidth Delay Product (BDP) is how much data can transit a network at a given time between two points. True or False? Group of answer choicesTrue

True

What protocol does RTP rely on? ICMP UDP OSPF TCP

UDP