Network + v2 - 6.8 Checkpoint Review
What is the primary purpose of a wire map tester? To detect improper termination issues To increase the signal strength in a cable To identify the type of cable used To measure the length of a cable
Correct Answer: To detect improper termination issues Explanation A wire map tester is specifically designed to detect improper termination issues by checking for continuity, shorts, and incorrect pin-outs/terminations, making it an essential tool for ensuring cable integrity. While some advanced cable testers can measure cable length, the primary function of a basic wire map tester is not to measure length but to detect wiring and termination issues. A wire map tester does not have the capability to increase signal strength. Its purpose is to test the physical wiring and termination of cables, not to enhance signal transmission. Identifying the type of cable used is not a function of a wire map tester. This device focuses on detecting wiring and termination problems, not on identifying cable materials or categories. References 2.6.4 Cable Testers 2.6.5 Wire Map Testers and Tone Generators
What does a successful ping command output include? The encryption level of the response The number of encrypted packets The message "Reply from IPAddress" The message "Request timed out"
Correct Answer: The message "Reply from IPAddress" Explanation A successful ping command output shows the message "Reply from IPAddress" along with the time it takes for the server's response to arrive, indicating successful communication with the target host. The ping command does not deal with encryption levels. The "Request timed out" message indicates an unsuccessful ping attempt. The ping command does not provide information about encrypted packets. References 4.4.3 arp 4.4.4 ping 4.4.5 Lab: IPv4 Troubleshooting Tools 4.4.7 Lab: Use IPv4 Test Tools 6.4.8 Lab: Explore DHCP Troubleshooting 6.4.10 Lab: Troubleshoot IP Configuration 2 6.4.11 Lab: Troubleshoot IP Configuration 3 6.5.15 Lab: Troubleshoot DNS Records 6.6.1 Client DNS Issues 6.6.2 Name Resolution Issues 9.4.10 Applied Live Lab: Analyze Network Attacks
A network technician is troubleshooting a newly installed Cat6 cabling system in an office environment. Users are experiencing intermittent network connectivity issues. Upon inspection, the technician notices that the cable bundles are cinched tightly with cable ties in several places along their run. What is the MOST likely cause of the connectivity issues? The use of cable ties is causing Alien Crosstalk. The cable length exceeds the maximum allowed for Cat6. The network is congested due to high traffic. The cables are not compatible with the network equipment.
Correct Answer: The use of cable ties is causing Alien Crosstalk. Explanation The use of cable ties is causing Alien Crosstalk is the correct answer. Cinching cable bundles too tightly with cable ties can cause Alien Crosstalk, where signal traffic from cables in close proximity interferes with each other. This can lead to intermittent connectivity issues as described. While cable length can affect signal quality, the scenario specifically points to the use of cable ties as a significant change, making Alien Crosstalk a more likely cause. Compatibility issues between cables and network equipment would likely result in consistent, not intermittent, connectivity problems. Network congestion might slow down the network but wouldn't typically cause intermittent connectivity issues related to physical cabling. References 2.6.7 Crosstalk Issues
What file in Linux contains the DNS server addresses? /etc/hosts /etc/resolv.conf /etc/network/interfaces /etc/dhcp/dhclient.conf
Correct Answer: /etc/resolv.conf Explanation In Linux, the file /etc/resolv.conf contains the DNS server addresses that the system uses for name resolution. /etc/hosts is used for static mappings of host names to IP addresses. /etc/dhcp/dhclient.conf is used for DHCP client configuration, not specifically for DNS. /etc/network/interfaces is used for network interface configuration, not specifically for DNS. References 6.5.1 Host Names and Domain Names 6.5.2 DNS Hierarchy 6.5.3 Name Resolution Using DNS 6.5.4 Resource Record Types 6.5.5 Host Address and Canonical Name Records 6.5.6 Mail Exchange, Service, and Text Records 6.5.7 Pointer Records 6.5.8 DNS Server Configuration 6.5.9 Internal vs External DNS 6.5.10 DNS Security 6.5.11 Lab: Configure DNS Addresses 6.5.12 Lab: Create Standard DNS Zones 6.5.13 Lab: Create Host Records 6.5.14 Lab: Create CNAME Records 6.5.15 Lab: Troubleshoot DNS Records 6.5.16 Configuring DNS Caching on Linux 6.5.17 Applied Live Lab: Configure DNS Records 6.6.1 Client DNS Issues 6.6.2 Name Resolution Issues 6.6.3 nslookup 6.6.4 dig 6.6.5 Lab: Explore nslookup 6.6.6 Lab: Use nslookup 6.6.7 Applied Live Lab: Report DNS Configuration
A system that contains custom applications routinely crashes. IT decides to upgrade the operating system after speaking with application support personnel, and testing the problem. What should IT do next to troubleshoot the issue? Determine if anything has changed. Verify full system functionality and, if applicable, implement preventive measures. Establish a plan of action. Identify the problem.
Correct Answer: Establish a plan of action. Explanation Establishing a plan of action, such as a maintenance window or scheduled downtime to fix an issue, is the best practice. Researching the impacts of any fixes should also be considered. While it is important to take enough time to identify the problem, IT has already identified the problem by speaking with support personnel, and they now need to establish a plan of action in order to resolve the issue. Determining if anything has changed is part of the testing process to see if the identified problem is consistently manifesting itself. IT has already completed this step in the troubleshooting process Verifying full system functionality is useful to identify the results and effects of a solution. It also includes ensuring that the problem is not repeatable and putting possible safeguards and restrictions in place to help prevent further issues. Once again, this is part of the testing process which has already been completed by IT. References 1.4.1 Network Troubleshooting Methodology 1.4.6 Establish a Plan of Action 1.4.10 Lab: Troubleshooting Methodology
What is the primary metric used by the Routing Information Protocol (RIP) to determine the best path to a destination network? Delay Incorrect answer: Bandwidth Load Hop Count
Correct Answer: Hop Count Explanation RIP uses hop count as its metric to determine the best path. A hop count is the number of routers a packet must pass through to reach its destination. The path with the lowest hop count is considered the best path. Bandwidth, delay, and load are metrics used by other routing protocols, not RIP. RIP does not consider the bandwidth of the links between routers when determining the best path. RIP does not take into account the delay on the links between routers. RIP does not consider the load on the network or routers when determining the best path. References 5.2.1 Dynamic Routing Protocols 5.2.6 Route Selection
A helpdesk operator is troubleshooting communications between devices in the same location, but one is having issues communicating with the others. Which of the following will have issues? Host D: IP: 192.168.0.10, Mask: 255.255.255.0 Host A: IP: 192.168.1.10, Mask: 255.255.255.0 Host B: IP: 192.168.1.11, Mask: 255.255.255.0 Host C: IP: 192.168.1.21, Mask: 255.255.0.0
Correct Answer: Host D: IP: 192.168.0.10, Mask: 255.255.255.0 Explanation Host D will not be able to communicate with the others. Host C cannot contact host D, as it thinks that host D is on the same local network. In fact, Host C needs to route messages for 192.168.0.0/24 via the default gateway. Hosts A and B have the same subnet mask. Host C will be able to use ARP messaging and receive replies. Host B has the same subnet mask as Host A. Host C will be able to use ARP messaging and receive replies. Host C will be able to use ARP messaging and receive replies to hosts A and B. References 4.2.2 Network Masks
A company is experiencing network issues where client devices frequently lose connectivity and must obtain new IP addresses more often than desired. The network administrator discovers that the DHCP lease time is set very low, causing IP addresses to be released and renewed too frequently. The administrator decides to adjust the DHCP configuration to alleviate this issue. To reduce the frequency of IP address renewals and improve network stability, which DHCP setting should the administrator adjust? Increase the lease time Decrease the T1 timer Decrease the T2 timer Increase the number of DHCP options
Correct Answer: Increase the lease time Explanation Increasing the lease time is correct because increasing the lease time will allow client devices to retain their IP addresses for a longer period, reducing the frequency of renewals and improving network stability. Decreasing the T1 timer would cause the client to attempt to renew its lease even earlier, potentially exacerbating the issue of frequent renewals. Decreasing the T2 timer would lead to earlier attempts to rebind to any available DHCP server if the original server does not respond, which does not address the issue of frequent lease renewals. Adding more DHCP options does not directly affect the frequency of IP address renewals. The number of DHCP options configured is unrelated to lease time settings. References 6.2.1 DHCP Process 6.2.2 DHCP Server Configuration 6.2.3 DHCP Options 6.2.5 Lab: Configure a DHCP Server 6.2.10 Lab: Configure Client Addressing for DHCP 6.3.2 IPv6 Interface Autoconfiguration and Testing
What action does a client take if it fails to rebind its lease configuration after the T2 timer expires? It switches to a static IP configuration. It renews the lease with the original DHCP server. It continues to broadcast to discover a server. It permanently retains the IP address.
Correct Answer: It continues to broadcast to discover a server. Explanation If a client cannot rebind its lease after the T2 timer, it enters a state of seeking a new DHCP server to obtain an IP address, ensuring it does not remain without network connectivity. DHCP does not allow clients to permanently retain IP addresses without server approval. It renews the lease with the original DHCP server is incorrect. At this stage, the client is attempting to find any server, not just the original. DHCP clients do not automatically switch to static configurations; this requires manual configuration. References 6.2.1 DHCP Process 6.2.2 DHCP Server Configuration 6.2.3 DHCP Options 6.2.5 Lab: Configure a DHCP Server 6.2.10 Lab: Configure Client Addressing for DHCP 6.3.2 IPv6 Interface Autoconfiguration and Testing
Why should user data traffic be avoided over the default VLAN? It increases the risk of VLAN hopping attacks. It automatically encrypts the data, making it unreadable. It is a best practice to reserve the default VLAN for voice traffic only. It limits the bandwidth available for management traffic.
Correct Answer: It increases the risk of VLAN hopping attacks. Explanation Keeping user data off the default VLAN is a security measure to prevent VLAN hopping attacks, where an attacker could gain unauthorized access to different network segments. VLANs do not encrypt data; they segment traffic. The concern with using the default VLAN for user data is not bandwidth but security. The default VLAN should ideally be unused for user data to minimize security risks, not specifically reserved for any particular type of traffic. References 5.6.1 Virtual LANs and Subnets
In a hub-based Ethernet network, how is a broadcast transmission handled? It is amplified and sent only to devices within a predefined group. It is filtered by the hub and only sent to the device that requested the data. It is ignored by the hub to prevent network congestion. It is sent to all hosts in the same logical network area.
Correct Answer: It is sent to all hosts in the same logical network area. Explanation Hubs, by their nature as multiport repeaters, broadcast every incoming signal to all connected devices. This includes broadcast transmissions, which are intended for all devices within the network segment. The hub does not have the capability to filter or selectively forward these transmissions; it simply amplifies the signal and sends it out through all ports, ensuring that all devices in the same logical network area receive the broadcast. Hubs do not have the capability to filter data or understand which device requested data. They broadcast all incoming signals to all connected devices. Hubs do not have the capability to identify or create predefined groups of devices. They treat all connected devices equally and broadcast data to all of them. Hubs do not ignore any transmissions. They are designed to amplify and rebroadcast all incoming signals to ensure that the data reaches all connected devices. References 1.3.3 Data Link Layer Functions 3.2.1 Hubs 3.2.3 Switches 3.2.4 Ethernet Switch Types 3.2.5 Switch Interface Configuration 3.2.7 Lab: Install a Switch in the Rack 3.2.8 Lab: Secure a Switch
Angela is the network administrator for a rapidly growing company with a 100BaseT network. Users have recently complained about slow file transfers. While checking network traffic, Angela discovers a high number of collisions. Which connectivity device would BEST reduce the number of collisions and allow future growth? Router Switch Bridge Hub
Correct Answer: Switch Explanation A switch would be the best choice in this situation. A bridge would segment traffic and reduce collisions, but it would be harder to maintain and harder to add new bridges as the network grows. A router would also allow growth and reduce collisions, but switches can provide those benefits at a lower cost per port and offer more administration options. A hub is not a good choice in this scenario. References 1.3.3 Data Link Layer Functions 3.2.1 Hubs 3.2.3 Switches 3.2.4 Ethernet Switch Types 3.2.5 Switch Interface Configuration 3.2.7 Lab: Install a Switch in the Rack 3.2.8 Lab: Secure a Switch
What does the term "channel link" refer to in the context of Ethernet connectivity? The entire cable path, including patch cords and the permanent link The protocol used for encrypting data over the network The wireless connection between a host and the networ The software configuration that enables network communication
Correct Answer: The entire cable path, including patch cords and the permanent link Explanation The entire cable path, including patch cords and the permanent link is the correct answer. In the context of Ethernet connectivity, a channel link refers to the complete physical path that data travels through, including both the patch cords (temporary links) and the structured cabling or permanent link. This encompasses all physical components from the host's network interface to the network switch. A channel link specifically refers to physical, wired connections in the context of Ethernet connectivity, not wireless connections. While software configurations are crucial for network communication, the term "channel link" specifically refers to the physical components of network connectivity, not software or configuration settings. The term "channel link" does not relate to data encryption protocols or any other method of securing data. It specifically refers to the physical aspects of network connectivity. References 2.6.2 Cable Issues
What happens when an Ethernet bridge receives a frame with a MAC address that is not in its forwarding database? The frame is dropped. The frame is flooded to all segments except for the source segment. The frame is forwarded to the specific port associated with the MAC address. The bridge sends a request to all ports to identify the destination MAC address.
Correct Answer: The frame is flooded to all segments except for the source segment. Explanation When an Ethernet bridge receives a frame with an unknown MAC address (not in its forwarding database), it floods the frame to all segments except the one it originated from. This behavior ensures that the frame reaches its intended destination even if the bridge does not yet know which port to use for forwarding. The bridge does not drop the frame; instead, it attempts to deliver it to the intended destination by flooding it to all other segments. The bridge cannot forward the frame to a specific port if the MAC address is not in its forwarding database; it floods the frame instead. Bridges do not send requests to identify the destination MAC address. They learn MAC addresses by listening to traffic and update their forwarding database accordingly. References 3.2.2 Bridges
At Layer 4 of the OSI model, which mechanism is responsible for ensuring reliable data delivery between hosts? The assignment of IP addresses to route packets to their destination The use of port numbers to identify different types of network traffic The encryption of data to prevent unauthorized access during transmission The implementation of flow control and error-checking protocols
Correct Answer: The implementation of flow control and error-checking protocols Explanation The implementation of flow control and error-checking protocols is the correct answer. Layer 4, the Transport layer, is responsible for providing reliable data delivery when required by applications. This is achieved through the implementation of flow control and error-checking protocols, such as TCP (Transmission Control Protocol), which ensure that packets are delivered in order and without errors. If packets are lost or damaged, these protocols can request that the data be resent, thus maintaining the integrity of the communication. While port numbers are used at the Transport layer to identify the type of network application and facilitate multiplexing, they do not play a direct role in ensuring the reliable delivery of data. Encryption is a security measure used to protect data from unauthorized access and is not directly related to the reliability of data delivery. It does not ensure that packets are delivered without loss or error. IP addresses are used at the Network layer (Layer 3) to route packets through an internetwork to their destination. While routing is essential for packet delivery, it is not a mechanism of the Transport layer that ensures reliable data delivery. References 1.2.1 Open Systems Interconnection Model 1.2.6 Layer 4 - Transport 1.2.8 OSI Model Summary 1.3.5 Transport and Application Layer and Security Functions 1.3.7 Binary and Hexadecimal 1.3.8 Lab: Explore a Single Location in a Lab 14.3.5 Cloud Firewall Security
What is the purpose of a default route in a routing table? To provide a route for traffic destined to a specific IP address with a /32 (IPv4) or /128 (IPv6) prefix To represent subnets for which the router does not have a local interface To manually add a route that only changes if edited by the administrator To identify the next hop router for destinations that cannot be matched by another routing table entry
Correct Answer: To identify the next hop router for destinations that cannot be matched by another routing table entry Explanation A default route is used when the routing table does not contain an exact match for the destination network or host. It specifies the next hop router to use for such traffic, effectively acting as the "gateway of last resort." To provide a route for traffic destined to a specific IP address with a /32 (IPv4) or /128 (IPv6) prefix describes a host route, which is a route to a specific IP address and has a /32 (IPv4) or /128 (IPv6) prefix. To manually add a route that only changes if edited by the administrator describes a static route, which is manually added to the routing table and remains unchanged unless manually edited by an administrator. To represent subnets for which the router does not have a local interface confuses the concept of remote routes with the purpose of a default route. Remote routes are for subnets and IP networks not directly attached, but a default route specifically provides a next hop for unmatched destinations. References 5.1.2 Static and Default Routes 5.1.3 Routing Table Example 5.1.4 Packet Forwarding
What is the purpose of using a hot aisle/cold aisle layout in a data center? To increase the density of servers in a rack To enhance physical security of the servers To simplify cable management To maximize cooling efficiency
Correct Answer: To maximize cooling efficiency Explanation A hot aisle/cold aisle layout is designed to maximize cooling efficiency by ensuring that hot air expelled from exhaust vents does not mix with the cool air drawn in through intake vents. This layout helps in maintaining optimal operating temperatures for the equipment. Increasing the density of servers in a rack is related to how many units can be fitted into a given space, not cooling. Enhancing physical security of the servers is achieved through other means, such as lockable doors. Simplifying cable management is not the primary purpose of a hot aisle/cold aisle layout, though it may indirectly affect it. References 2.5.1 Rack Systems 2.5.2 Humidity and Temperature
A cybersecurity analyst is investigating a series of suspicious network activities that have been flagged by the intrusion detection system. The analyst notices a pattern of packets that have unusually large sizes, which could indicate an attempt to exploit vulnerabilities through fragmentation attacks. To further analyze these packets and identify potential threats, the analyst decides to examine the IPv4 datagram headers of the captured packets. Which field in the IPv4 datagram header should the analyst focus on to determine the size of these packets and assess the risk of fragmentation attacks? Time to Live (TTL) field Identification field Total Length field Fragment Offset field
Correct Answer: Total Length field Explanation The Total Length field in the IPv4 datagram header specifies the total size of the packet, including the header and the payload. By examining this field, the cybersecurity analyst can determine the size of the packets and assess the risk of fragmentation attacks, as large packet sizes could be indicative of such threats. The Identification field is used as part of IP fragmentation and reassembly, helping to identify fragments of the original IP datagram that belong together, but it does not indicate the size of the packet. The Fragment Offset field is used in the fragmentation process to indicate where a fragment fits within the original packet. While it is related to fragmentation, it does not provide information on the total size of the packet. The Time to Live (TTL) field is used to limit the lifespan of a packet, determining how many hops (routers) the packet can pass through before being discarded. It does not provide information on packet size or fragmentation. References 4.1.1 IPv4 Datagram Header
How is SOHO subscriber Internet access PRIMARILY facilitated? Through satellite communication systems Using only wireless cellular networks Through direct fiber-optic connections to each home Via the public switched telephone network (PSTN)
Correct Answer: Via the public switched telephone network (PSTN) Explanation Most SOHO subscriber Internet access is facilitated via the PSTN. This involves using a modem connected to the telephone line, which is a widespread and accessible method for Internet connectivity. The PSTN is a global system of interconnected voice-oriented public telephone networks, both commercial and government-owned. While satellite communication systems can provide Internet access, especially in remote areas, they are not the primary means of facilitating Internet access for SOHO (Small Office/Home Office) subscribers. Satellite systems often have higher latency and can be more expensive compared to other methods. While wireless cellular networks (such as 3G, 4G, and 5G) provide Internet access and are increasingly used for mobile Internet connectivity, they are not the primary method for facilitating Internet access for SOHO subscribers. Cellular networks are more commonly used for mobile devices and in areas where traditional broadband access is not available. Direct fiber-optic connections, although offering high-speed Internet access, are not the primary means of facilitating Internet access for SOHO subscribers. The deployment of fiber-optic connections is growing but is still limited by high installation costs and is not as widespread as PSTN-based access. References 1.2.1 Open Systems Interconnection Model 1.2.5 Layer 3 - Network 1.2.8 OSI Model Summary 1.3.4 Network Layer Functions 1.3.6 The Internet 1.3.7 Binary and Hexadecimal 1.3.8 Lab: Explore a Single Location in a Lab 4.1.2 Layer 2 vs Layer 3 Addressing and Forwarding 13.1.1 Wide Area Networks and the OSI Model 14.3.5 Cloud Firewall Security
What type of sprinkler system holds water at high pressure and discharges water when triggered by heat? Halon Wet-pipe Dry-pipe Pre-action
Correct Answer: Wet-pipe Explanation Wet-pipe sprinkler systems constantly hold water at high pressure and discharge water when triggered by heat, making them quick to respond to fires. Dry-pipe systems are used in areas where freezing is possible. Pre-action systems require an alarm trigger before filling with water. Halon is a gas-based fire suppression system. References 2.5.4 Fire Suppression
