200-901 Network Fundamentals Practice Test 8 — 15 Questions

Question 1

An administrator is configuring DNS records for a company's domain. Which three DNS record types are most commonly used to map hostnames to IP addresses or aliases? (Choose three.)

Accepted Answer

AAAA. Option A (AAAA) is correct because an AAAA record maps a hostname to an IPv6 address, directly fulfilling the hostname-to-IP mapping purpose. Option B (CNAME) is correct because a Canonical Name record creates an alias from one hostname to another hostname, which is the alias-mapping function described in the question. Option C (A) is correct because an A record maps a hostname to an IPv4 address, the most fundamental hostname-to-IP mapping. Option D (MX) is not correct here because MX records designate mail exchangers for email delivery, not hostname-to-IP or alias mapping. Option E (PTR) is not correct because PTR records provide reverse DNS lookups, mapping IP addresses back to hostnames rather than hostnames to IP addresses.

Answer

MX

Answer

PTR

Question 2

An organization is planning to implement HTTPS for their web services. Which three statements accurately describe the HTTPS protocol? (Choose three.)

Accepted Answer

HTTPS uses TLS to encrypt HTTP traffic.. HTTPS uses TLS for encryption, involves certificate verification, and negotiates a symmetric session key. It does not use UDP typically (TCP is used) and it is not stateless after the handshake.

Answer

HTTPS uses UDP as the transport protocol.

Answer

HTTPS is stateless after the initial handshake.

Question 3

A network engineer is analyzing traffic and needs to identify which applications use UDP. Which three applications commonly use UDP as their transport protocol? (Choose three.)

Accepted Answer

DHCP. DHCP (A) is correct because it uses UDP ports 67 (server) and 68 (client) for its broadcast-based DORA process, since UDP's connectionless nature suits the initial address assignment before a client has an IP. DNS (D) is correct because standard DNS queries and responses use UDP port 53 for lightweight, fast lookups, falling back to TCP only for large responses or zone transfers. NTP (E) is correct because it uses UDP port 123 for time synchronization, where occasional packet loss is acceptable and the low overhead of UDP is preferred. SSH (B) is not correct because it relies on TCP port 22 for reliable, ordered, connection-oriented sessions. SMTP (C) is not correct because it uses TCP port 25 (and 587/465) to guarantee reliable delivery of mail messages.

Answer

SSH

Answer

SMTP

Question 4

A developer runs a Python script that calls a REST API on a remote server. The script hangs indefinitely with no response. The developer opens a terminal and runs `curl -v https://api.example.com/status`. The output shows that the TCP three-way handshake completes, but the TLS handshake never starts. Which of the following is the most likely cause?

Accepted Answer

A network device is intercepting the connection and terminating it before TLS negotiation.. The key symptom is that the TCP three-way handshake succeeds but the TLS handshake never initiates. This indicates that something between the client and server is completing the TCP connection and then preventing the TLS negotiation from starting. A transparent proxy or firewall that terminates TCP connections without forwarding them can cause this exact behavior. The other options either contradict the observed TCP success or describe failures that would occur after TLS begins.

Answer

The server is not listening on port 443, so the TCP handshake should have failed.

Answer

A firewall is blocking outbound TCP port 80.

Answer

The client is using an outdated version of TLS that the server does not support.

Question 5

A network administrator is configuring a new subnet on a Cisco switch. The subnet uses the address 192.168.10.0/24. The administrator needs to assign an IP address to the switch's management interface so it can be reached from a remote management station on the same subnet. Which of the following IP addresses should be assigned to the switch?

Accepted Answer

192.168.10.1. For a device to be reachable on the same subnet as a management station, it must be assigned a valid host address within that subnet. In 192.168.10.0/24, the addresses 192.168.10.0 and 192.168.10.255 are reserved as the network and broadcast addresses, respectively. Any other address, such as 192.168.10.1, is a usable host address. 192.168.11.1 is in a different subnet and would require routing.

Answer

192.168.11.1

Answer

192.168.10.255

Answer

192.168.10.0

Question 6

A network engineer is analyzing a packet capture and notices that a host is sending a TCP segment with the SYN flag set and the ACK flag not set. The destination port is 443. Which of the following best describes what the host is attempting to do?

Accepted Answer

The host is initiating a TCP connection to a server on port 443.. The SYN flag without ACK is used to initiate a TCP connection. When a host sends a segment with SYN set and ACK not set to port 443, it is starting the three-way handshake to establish a connection to an HTTPS server. The server would respond with a SYN-ACK, and the client would complete the handshake with an ACK. This is fundamental TCP behavior.

Answer

The host is terminating an existing TCP connection to port 443.

Answer

The host is acknowledging a previous SYN-ACK and completing the three-way handshake.

Answer

The host is responding to an incoming connection request on port 443.

Question 7

A network engineer is analyzing a packet capture of a TCP session establishment between a client and a server. The engineer observes a packet with the SYN flag set and another with both the SYN and ACK flags set. Which flag will be set in the next packet sent by the client to complete the three-way handshake?

Accepted Answer

ACK. The three-way handshake is a fundamental TCP connection establishment process. The client sends a SYN packet, the server responds with a SYN-ACK packet, and the client completes the handshake by sending an ACK packet. This final ACK acknowledges the server's SYN and confirms that both sides are ready to exchange data.

Answer

RST

Answer

PSH

Answer

FIN

Question 8

A developer is writing a Python script that must retrieve the current operational state of a Cisco IOS XE device through its RESTCONF API. The device uses YANG models, and the script must read interface statistics without altering the configuration. Which HTTP method should the script use, and what is the correct URL structure?

Accepted Answer

Use GET with the URL https://<device>/restconf/data/ietf-interfaces:interfaces. RESTCONF uses HTTP methods that map to CRUD operations: GET reads data, POST creates, PUT replaces, and DELETE removes. To read interface statistics without modifying configuration, the script must use GET against the data resource identified by the module-qualified YANG container. The URL must include /restconf/data and the correct module prefix to locate the interfaces container in the datastore.

Answer

Use POST with the URL https://<device>/restconf/data/ietf-interfaces:interfaces

Answer

Use PUT with the URL https://<device>/restconf/data/ietf-interfaces:interfaces

Answer

Use GET with the URL https://<device>/restconf/operations/ietf-interfaces:interfaces

Question 9

A developer runs `curl -I http://api.example.com/health` and receives `HTTP/1.1 301 Moved Permanently` with a `Location: https://api.example.com/health` header. They want to follow the redirect automatically and print the final response body. Which curl option should they add?

Accepted Answer

`-L`. Following an HTTP redirect requires curl to recognize the 3xx status and reissue the request to the URL in the Location header. The `-L` flag enables exactly that behavior. Other flags alter TLS verification, verbosity, or the request method, but none of them cause curl to traverse the redirect chain. Combining `-L` with a method that returns a body is what produces the final content.

Answer

`-v`

Answer

`-X GET`

Answer

`-k`

Question 10

A network automation script on a Cisco IOS XE device needs to retrieve the current running configuration and then compare it against a known-good baseline stored on a Git server. The script must use a protocol that encrypts all data in transit and supports programmatic, structured retrieval of the configuration without screen-scraping. Which approach should the script use?

Accepted Answer

Use NETCONF over SSH on port 830 with the operation and source .. NETCONF over SSH provides an encrypted, standards-based transport on port 830 and represents configuration as structured XML in datastores. The operation with a running source returns the device configuration in a machine-parseable form, avoiding the fragility of CLI scraping. This satisfies both the encryption requirement and the need for reliable, programmatic retrieval for baseline comparison.

Answer

Use SSH on port 22 and parse the output of the show running-config command.

Answer

Use SNMPv3 with authPriv to walk the ifTable and reconstruct the configuration.

Answer

Use Telnet on port 23 and parse the output of the show running-config command.

Question 11

A developer is writing a script that uses the Cisco SD-WAN vManage REST API to retrieve a list of devices. The script uses the GET method to https://vmanage.example.com/dataservice/device. The API returns a 401 Unauthorized status code. Which of the following should the developer do to resolve the issue?

Accepted Answer

Include a valid authentication token in the request header.. The 401 Unauthorized status code indicates that the request lacks valid authentication credentials. For the Cisco SD-WAN vManage API, developers must authenticate first, usually by obtaining a session token, and then include that token in subsequent requests. Without it, the API rejects the request. The other options address different issues such as method, TLS, or query parameters, which would produce different error codes.

Answer

Ensure the request URL includes the correct query parameters for device filtering.

Answer

Verify that the vManage server's TLS certificate is trusted by the client.

Answer

Change the HTTP method to POST.

Question 12

A network administrator is configuring a switch and needs to ensure that devices connected to the same VLAN can communicate with each other. The administrator wants to verify that the switch is correctly forwarding frames within the VLAN. Which of the following best describes the switch's primary function in this scenario?

Accepted Answer

It forwards frames based on MAC addresses within the same VLAN.. A switch's primary function is to forward frames based on MAC addresses within a VLAN. It learns source MAC addresses and builds a MAC address table, then forwards frames only to the port where the destination MAC is known, enabling efficient communication within the same VLAN while isolating traffic from other VLANs.

Answer

It translates IP addresses to MAC addresses for communication.

Answer

It routes packets between different VLANs using IP addresses.

Answer

It broadcasts all frames to every port to ensure delivery.

Question 13

A developer is writing a script that must resolve a hostname to an IPv4 address before making an HTTP request. The script uses a DNS resolver library and needs to query for the appropriate record type. Which DNS record type should the script query to obtain the IPv4 address?

Accepted Answer

A. The A record is the DNS record type that maps a hostname to an IPv4 address. When a script needs to resolve a hostname to an IPv4 address for an HTTP request, it should query for an A record. Other record types serve different purposes, such as AAAA for IPv6, CNAME for aliases, and MX for mail routing.

Answer

CNAME

Answer

MX

Answer

AAAA

Question 14

A network engineer is deploying a new application that requires low-latency, high-throughput communication between two data centers. The engineer decides to use UDP instead of TCP for the application's transport protocol. Which two characteristics of UDP make it suitable for this scenario? (Choose two.)

Accepted Answer

UDP has a smaller header size compared to TCP, reducing bandwidth overhead.. UDP is suitable for low-latency, high-throughput communication because it is connectionless, avoiding the overhead of establishing and maintaining a connection, and it has a smaller header size, reducing per-packet overhead. These characteristics make UDP ideal for real-time applications where speed is critical and some packet loss is tolerable. The other options describe features of TCP or incorrectly attribute reliability and congestion control to UDP.

Answer

UDP guarantees packet ordering and delivery.

Answer

UDP provides reliable delivery through acknowledgments and retransmissions.

Answer

UDP performs congestion control to avoid network congestion.

Question 15

A network engineer captures traffic between a client and a server. The client sends a TCP segment with the SYN flag set. The server responds with a segment that has both SYN and ACK flags set. Which field in the server's response acknowledges the client's initial sequence number?

Accepted Answer

The acknowledgment number field, set to the client's initial sequence number plus one.. During the TCP three-way handshake, the server's SYN-ACK segment acknowledges the client's SYN by placing the client's initial sequence number plus one in the acknowledgment number field. This confirms receipt of the SYN and establishes the client's sequence space. The sequence number field carries the server's own ISN, while window size and urgent pointer serve flow control and urgent data handling, respectively.

Answer

The window size field, set to the number of bytes the server can receive.

Answer

The urgent pointer field, set to indicate out-of-band data.

Answer

The sequence number field, set to the server's own initial sequence number.