200-901 Network Fundamentals Practice Test 9 — 15 Questions

Question 1

A developer is troubleshooting an application that uses HTTP/2. The developer notices that multiple requests are being sent concurrently over a single TCP connection, and the responses are being received out of order. Which HTTP/2 feature allows this behavior?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Multiplexing. HTTP/2 multiplexing allows multiple request and response messages to be interleaved on a single TCP connection. Each stream is independent, and responses can be received out of order, eliminating head-of-line blocking at the HTTP level and improving performance by enabling parallel transfers without opening multiple connections.

Answer

Binary framing

Answer

Server push

Answer

Header compression

Question 2

A developer is configuring a new application server and needs to allow HTTP traffic from web clients. Which port should be opened on the firewall to permit standard unencrypted HTTP traffic?

Accepted Answer

Port 80. HTTP by default uses TCP port 80 for unencrypted communication. When a client makes an HTTP request to a web server, it connects to port 80 unless another port is specified. Therefore, to allow standard HTTP traffic, the firewall must permit inbound connections on port 80.

Answer

Port 22

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Port 53

Answer

Port 443

Question 3

A developer is building a Python script that must resolve a hostname to an IPv4 address and then connect to a specific TCP port. The script uses `socket.getaddrinfo(host, port, family=socket.AF_INET, type=socket.SOCK_STREAM)`. What does the returned list contain?

Accepted Answer

Tuples of (family, type, proto, canonname, sockaddr) for each address that matches the criteria.. `socket.getaddrinfo` resolves a host and service into a list of 5-tuples containing family, type, protocol, canonical name, and socket address. When filtered with `AF_INET` and `SOCK_STREAM`, the results are IPv4 TCP endpoints ready for socket creation. This design supports multiple addresses and protocol independence, which is why developers use it instead of the simpler but less flexible `gethostbyname`.

Answer

A dictionary mapping address families to lists of IPv4 addresses.

Answer

A single string containing the IPv4 address in dotted-decimal notation.

Answer

A list of `ipaddress.IPv4Address` objects representing resolved addresses.

Question 4

A network engineer is analyzing traffic patterns and wants to identify characteristics of UDP that affect real-time applications such as VoIP and video streaming. Which two characteristics of UDP make it suitable for these applications? (Choose two.)

Accepted Answer

Low overhead due to a minimal header. UDP is suitable for real-time applications because it has low overhead from a minimal header and is connectionless, which reduces latency. These characteristics allow VoIP and video streaming to prioritize speed over reliability, as retransmissions would cause unacceptable delays.

Answer

Ordered delivery of packets

Answer

Guaranteed delivery of packets

Answer

Built-in congestion control

Question 5

A developer is writing a Python script using requests to retrieve a large JSON payload from an API. The server responds with headers including Content-Encoding: gzip, and the response body appears as binary data. The script must automatically decompress the payload to parse it as JSON. Which requests library behavior should the developer rely on?

Accepted Answer

The requests library automatically decompresses gzip-encoded responses when accessing response.text or response.json().. The requests library automatically decompresses gzip-encoded responses when the developer accesses response.text or response.json(). This behavior is driven by the Content-Encoding header and allows seamless parsing of JSON payloads without manual gzip handling. Using response.content returns raw compressed bytes, so the higher-level accessors are necessary for this scenario.

Answer

The developer must set the Accept-Encoding header to identity to force the server to send uncompressed JSON.

Answer

The response.content attribute automatically decodes gzip-encoded bodies before returning them.

Answer

The response.json() method requires the developer to pass a decompression parameter set to True.

Question 6

A network administrator is configuring a switch and needs to segment traffic into multiple broadcast domains while also allowing communication between them. Which device or feature should be used to achieve this?

Accepted Answer

VLANs on a switch. VLANs are used to logically segment a switch into multiple broadcast domains. Each VLAN represents a separate broadcast domain, and devices within a VLAN can communicate at Layer 2. To enable communication between VLANs, inter-VLAN routing is needed. STP, EtherChannel, and port mirroring do not create broadcast domains; they serve other purposes.

Answer

Port mirroring on a switch

Answer

STP on a switch

Answer

EtherChannel on a switch

Question 7

A developer is building a Python application that must connect to a REST API hosted on a server. The API requires a persistent connection and the ability to send multiple requests without re-establishing a TCP handshake each time. The developer wants to minimize latency. Which HTTP feature should the application leverage?

Accepted Answer

HTTP persistent connections (keep-alive). Persistent connections, enabled by the Connection: keep-alive header in HTTP/1.1, allow a client to reuse an existing TCP connection for multiple requests. This reduces latency by eliminating repeated TCP and TLS handshakes. While HTTP/2 multiplexing also improves efficiency, it requires server support and is not the basic feature described. The other options do not directly address the need for connection reuse.

Answer

HTTP pipelining

Answer

HTTP/2 multiplexing

Answer

HTTP cookies

Question 8

A developer is using the Python requests library to call a REST API on a Cisco DNA Center controller. The API requires a token for authentication. The developer writes code to obtain the token and then call the network-device endpoint. Which HTTP header must be included in the second request to authenticate using the token?

Accepted Answer

X-Auth-Token: <token>. Cisco DNA Center's REST API uses a token-based authentication mechanism. After obtaining the token from the authentication endpoint, the developer must include it in the X-Auth-Token header of subsequent requests. This header is specific to DNA Center and differs from standard Authorization headers used by other APIs.

Answer

Authorization: Bearer <token>

Answer

Cookie: JSESSIONID=<token>

Answer

Authorization: Basic <base64-encoded-credentials>

Question 9

A network automation engineer is using `ncclient` to configure a Cisco IOS XE device via NETCONF. The engineer wants to retrieve the running configuration using the `` operation with a source of ``. Which XML element must be included in the RPC to specify the data store?

Accepted Answer

``. The NETCONF `` operation requires a `` element to identify the configuration datastore to retrieve. The `` element within `` selects the running configuration. Other elements like `` are used for editing, `` for edit payloads, and `` for narrowing results. The engineer must use `` to correctly specify the datastore for retrieval.

Answer

`<target><running/></target>`

Answer

`<config><running/></config>`

Answer

`<filter><running/></filter>`

Question 10

A network engineer is configuring a new Cisco switch and needs to assign an IP address to a VLAN interface so that the switch can be managed remotely over the network. The engineer enters the commands: interface vlan 10, then ip address 192.168.10.2 255.255.255.0, then no shutdown. However, the interface remains down. What is the most likely cause?

Accepted Answer

The switch does not have any physical ports assigned to VLAN 10, so the VLAN interface is down.. A VLAN interface (SVI) on a Cisco switch remains down until the VLAN is active, which requires at least one physical port to be up and assigned to that VLAN. Simply creating the SVI and assigning an IP address is not enough. The engineer must assign an access port to VLAN 10 and ensure it is operational to bring the SVI up.

Answer

The no shutdown command must be issued from global configuration mode, not interface configuration mode.

Answer

The IP address is incorrectly configured because the subnet mask should be in CIDR notation.

Answer

VLAN 10 has not been created on the switch.

Question 11

A network engineer is troubleshooting a connectivity issue between two subnets. The engineer uses the traceroute command and observes that packets are reaching the destination but with high latency. Which of the following is the most likely cause of the high latency?

Accepted Answer

Network congestion causing packets to be queued at intermediate devices.. Network congestion causes packets to be queued at intermediate devices, increasing latency. Traceroute would show higher round-trip times at the congested hop, but packets still reach the destination. This is a common cause of high latency without packet loss.

Answer

Incorrect subnet mask configuration on the source device.

Answer

A routing loop causing packets to traverse multiple hops repeatedly.

Answer

A firewall blocking ICMP packets, causing retransmissions.

Question 12

A developer runs a Python script that uses the requests library to call a REST API endpoint. The script receives an HTTP 401 Unauthorized response. The developer confirms the URL is correct and the server is reachable. Which action should the developer take to resolve the issue?

Accepted Answer

Include a valid authentication token in the request's Authorization header.. An HTTP 401 Unauthorized status means the request lacks valid authentication credentials. The developer must provide a valid token or credentials, typically in the Authorization header. Changing the method, query parameters, or timeout does not address the authentication failure, so including a valid token is the correct resolution.

Answer

Verify that the API endpoint URL includes the correct query parameters.

Answer

Change the HTTP method from GET to POST.

Answer

Increase the request timeout value in the Python script.

Question 13

A network engineer is configuring a switch and needs to assign an IP address to a VLAN interface for management purposes. The engineer wants to ensure that devices on different VLANs can communicate through the switch. Which feature must be enabled on the switch to allow inter-VLAN routing?

Accepted Answer

IP routing. Inter-VLAN routing requires a Layer 3 device to forward packets between subnets. On a Layer 3 switch, enabling IP routing allows the switch to route between VLAN interfaces (SVIs). Each SVI is configured with an IP address and acts as the gateway for hosts in that VLAN. Without IP routing, the switch would only forward frames within the same VLAN.

Answer

Link Aggregation Control Protocol (LACP)

Answer

Spanning Tree Protocol (STP)

Answer

Port mirroring

Question 14

A developer is writing a Python script to interact with a REST API. The script must handle HTTP responses correctly. Which two HTTP status code ranges indicate a successful request and a client error, respectively? (Choose two.)

Accepted Answer

2xx. HTTP status codes are grouped into five classes. 2xx codes indicate successful request handling, such as 200 OK. 4xx codes indicate client errors, such as 404 Not Found or 400 Bad Request. 1xx, 3xx, and 5xx represent informational, redirection, and server error responses, respectively. Therefore, the correct ranges for success and client error are 2xx and 4xx.

Answer

3xx

Answer

1xx

Answer

5xx

Question 15

A network operations team is deploying a new application that requires guaranteed bandwidth and low latency between two data centers. The team decides to use MPLS Layer 3 VPN. Which component of MPLS is responsible for forwarding packets based on labels rather than traditional IP routing lookups?

Accepted Answer

Label Switch Router (LSR). In MPLS, the Label Switch Router (LSR) is the device that forwards packets based on labels. It uses the Label Forwarding Information Base (LFIB) to determine the outgoing interface and new label. This allows MPLS networks to make forwarding decisions without examining the IP header, enabling traffic engineering and VPNs. The LERs handle label imposition and disposition at the edges.

Answer

Label Edge Router (LER)

Answer

Autonomous System Boundary Router (ASBR)

Answer

Route Reflector