200-901 Network Fundamentals Practice Test 4 — 15 Questions

Question 1

Which OSI layer is responsible for routing packets across different networks?

Accepted Answer

Layer 3 (Network). The Network layer (Layer 3) is responsible for logical addressing and routing packets between different networks. Protocols like IP (IPv4/IPv6) use routing tables and algorithms (e.g., OSPF, BGP) to determine the best path for forwarding packets across multiple hops. Without Layer 3, traffic could not leave a local broadcast domain.

Answer

Layer 1 (Physical)

Answer

Layer 4 (Transport)

Answer

Layer 2 (Data Link)

Question 2

A network administrator configures a switch port to belong to VLAN 10. Which OSI layer is primarily involved in VLAN tagging?

Accepted Answer

Layer 2 (Data Link). VLANs operate at Layer 2 (Data Link) by adding tags to Ethernet frames.

Answer

Layer 1 (Physical)

Answer

Layer 3 (Network)

Answer

Layer 4 (Transport)

Question 3

An application requires reliable, ordered delivery of data. Which transport protocol should be used?

Accepted Answer

TCP. TCP provides reliability, ordered delivery, and connection-oriented communication.

Answer

UDP

Answer

HTTP

Answer

IP

Question 4

Which TCP flag is set in the second step of the three-way handshake?

Accepted Answer

SYN and ACK. The TCP three-way handshake begins with the client sending a SYN segment to initiate a connection. In the second step, the server responds with a SYN-ACK segment, which both acknowledges the client's SYN (using the ACK flag) and synchronizes its own sequence number (using the SYN flag). This combined flag is essential for establishing a reliable, bidirectional connection.

Answer

ACK

Answer

SYN

Answer

FIN

Question 5

Which of the following is a private IPv4 address range as defined by RFC 1918?

Accepted Answer

10.0.0.0/8. Private IPv4 ranges: 10.0.0.0/8, 172.16.0.0/12, 192.168.0.0/16.

Answer

172.32.0.0/12

Answer

172.15.0.0/12

Answer

192.167.0.0/16

Question 6

A network engineer is subnetting the network 192.168.1.0/24 into subnets that each support at least 50 hosts. What subnet mask should be used?

Accepted Answer

255.255.255.192 (/26). To support at least 50 hosts, you need 6 host bits (2^6 - 2 = 62 usable addresses). A /26 subnet mask (255.255.255.192) provides exactly 6 host bits, meeting the requirement. The original /24 network is borrowed with 2 subnet bits, yielding 4 subnets of 64 addresses each.

Answer

255.255.255.224 (/27)

Answer

255.255.255.240 (/28)

Answer

255.255.255.128 (/25)

Question 7

Which DNS record type is used to verify domain ownership for email security (SPF)?

Accepted Answer

TXT record. SPF (Sender Policy Framework) is stored in a TXT record.

Answer

A record

Answer

CNAME record

Answer

MX record

Question 8

What is the primary benefit of using HTTP/2 over HTTP/1.1?

Accepted Answer

It supports multiplexing. HTTP/2 introduces multiplexed streams, allowing multiple requests/responses in parallel over a single connection.

Answer

It is connectionless

Answer

It uses plain text for headers

Answer

It eliminates the need for TLS

Question 9

In the context of SDN, which API allows a network controller to communicate with the forwarding plane of network devices?

Accepted Answer

Southbound API. Southbound APIs (e.g., OpenFlow, NETCONF, gRPC) enable communication from the controller to the network devices.

Answer

Eastbound API

Answer

Northbound API

Answer

REST API

Question 10

Which wireless standard operates in both 2.4 GHz and 5 GHz bands and is commonly known as Wi-Fi 6?

Accepted Answer

802.11ax. 802.11ax (Wi-Fi 6) supports both 2.4 GHz and 5 GHz bands, offering improved efficiency.

Answer

802.11n

Answer

802.11ac

Answer

802.11g

Question 11

An engineer sees that a DNS query for 'www.example.com' returns a CNAME record. What does this mean?

Accepted Answer

The domain is an alias for another domain. A CNAME (Canonical Name) record maps an alias domain name to another canonical domain name. When a DNS query for 'www.example.com' returns a CNAME record, it means 'www.example.com' is an alias for another domain (e.g., 'example.com'), and the resolver must perform a second query to obtain the actual A or AAAA record. This is defined in RFC 1035 and is used to simplify domain management.

Answer

The domain has multiple IP addresses

Answer

The domain uses IPv6

Answer

The IP address is directly provided

Question 12

An application uses UDP. Which characteristic is true about this application's communication?

Accepted Answer

It is connectionless. UDP is a connectionless transport protocol, meaning it does not establish a dedicated end-to-end connection before sending data. This characteristic allows for low-latency, best-effort delivery without the overhead of connection setup, which is ideal for applications like DNS queries or streaming media where speed is prioritized over reliability.

Answer

It guarantees packet delivery

Answer

It retransmits lost packets

Answer

It performs a three-way handshake

Question 13

Which of the following is a non-overlapping channel in the 2.4 GHz Wi-Fi band?

Accepted Answer

Channel 6. Channels 1, 6, and 11 are non-overlapping in the 2.4 GHz band.

Answer

Channel 3

Answer

Channel 12

Answer

Channel 9

Question 14

Which TWO of the following are southbound protocols in SDN?

Accepted Answer

NETCONF. OpenFlow and NETCONF are southbound protocols used between controller and network devices.

Answer

OSPF

Answer

SNMP

Answer

REST

Question 15

Which THREE of the following are features of HTTP/2?

Accepted Answer

Header compression (HPACK). HTTP/2 is binary, supports multiplexed streams, and uses HPACK for header compression.

Answer

Plain text headers

Answer

Persistent connections