HP HPE3-U01 Aruba Certified Network Technician Exam (ACNT) Exam Practice Test

To establish a secure web connection to YouTube.com, the computer will run two protocols: DNS and HTTPS. DNS (Domain Name System) is a protocol that translates domain names into IP addresses, which are used to identify and locate web servers on the internet. HTTPS (Hypertext Transfer Protocol Secure) is a protocol that encrypts and authenticates data transfer between a web browser and a web server, ensuring the security and integrity of the communication.

The computer does not need to run DHCP (Dynamic Host Configuration Protocol), FTP (File Transfer Protocol), or HTTP5 (a non-existent protocol) to connect to YouTube.com. DHCP is a protocol that assigns IP addresses to devices on a network automatically, but the computer already has a static address configured. FTP is a protocol that transfers files between a client and a server, but it is not used for web browsing. HTTP5 is not a valid protocol name, and it is likely a typo for HTTP (Hypertext Transfer Protocol), which is the unsecure version of HTTPS. References:

• Aruba Certified Network Technician (ACNT) | HPE Aruba Networking
• 6 Network Security Protocols You Should Know | Cato Networks
• What is HTTPS? | Cloudflare

 The header in the exhibit belongs to the Internet Protocol version 4 (IPv4), which is the most widely used protocol for routing and delivering packets across networks. IPv4 is a connectionless and unreliable protocol that operates at the network layer of the OSI model. The IPv4 header consists of 20 bytes (160 bits) of fixed fields and up to 40 bytes (320 bits) of optional fields. The fixed fields include:

• Version: 4 bits that indicate the version of the IP protocol, which is 4 for IPv4.
• IHL (Internet Header Length): 4 bits that indicate the length of the IP header in 32-bit words, which is 5 for the minimum header size of 20 bytes.
• Type of Service: 8 bits that indicate the quality of service (QoS) parameters for the packet, such as precedence, delay, throughput, and reliability.
• Total Length: 16 bits that indicate the total length of the IP packet in bytes, including the header and the data.The maximum value is 65535 bytes.
• Identification: 16 bits that identify the packet for fragmentation and reassembly purposes.
• Flags: 3 bits that control the fragmentation of the packet. The first bit is reserved and must be zero. The second bit is the Don’t Fragment (DF) bit, which indicates whether the packet can be fragmented or not. The third bit is the More Fragments (MF) bit, which indicates whether the packet is the last fragment or not.
• Fragment Offset: 13 bits that indicate the position of the fragment in the original packet, measured in units of 8 bytes.
• TTL (Time To Live): 8 bits that indicate the maximum number of hops that the packet can traverse before being discarded. The TTL is decremented by one at each hop, and the packet is dropped if the TTL reaches zero.
• Protocol: 8 bits that indicate the protocol of the data carried in the packet, such as TCP, UDP, ICMP, etc. The protocol numbers are defined in the List of IP protocol numbers.
• Header Checksum: 16 bits that provide error detection for the IP header. The checksum is calculated by adding the 16-bit words of the header and taking the one’s complement of the result.The checksum is recomputed and verified at each hop.
• Source IP Address: 32 bits that indicate the IP address of the sender of the packet.
• Destination IP Address: 32 bits that indicate the IP address of the receiver of the packet.
• Options: Variable-length field that contains optional information for the IP packet, such as security, routing, timestamp, etc. The options are padded with zeros to make the header length a multiple of 32 bits.

The IPv4 header can be distinguished from other protocol headers by the value of the Version field, which is 4 for IPv4. Other protocol headers have different values for the Version field or do not have a Version field at all. For example, the IPv6 header has a Version field of 6, the UDP header does not have a Version field, the Ethernet header has a Type field instead of a Version field, and the TCP header has a Data Offset field instead of a Version field. References:

• Aruba Certified Network Technician (ACNT) | HPE Aruba Networking
• Aruba Documentation Portal
• Introduction and IPv4 Datagram Header - GeeksforGeeks
• Protocol header - Oxford Reference
• List of IP protocol numbers - Wikipedia

To convert a hexadecimal number to a binary number, we need to follow these steps:

• Write down the hexadecimal number and assign a power of 16 to each digit, starting from the rightmost with 16^0.
• Convert each hexadecimal digit to its decimal equivalent by multiplying it with its power of 16.
• Add all the decimal values to get the decimal equivalent of the hexadecimal number.
• Divide the decimal number by 2 repeatedly and write down the remainders from bottom to top.
• The binary number is the sequence of remainders obtained in the previous step.

Let’s apply these steps to the hexadecimal number 17:

• 17 = 1 × 16^1 + 7 × 16^0
• 17 = 16 + 7
• 17 = 23 in decimal
• 23 / 2 = 11 with remainder 1
• 11 / 2 = 5 with remainder 1
• 5 / 2 = 2 with remainder 1
• 2 / 2 = 1 with remainder 0
• 1 / 2 = 0 with remainder 1
• The binary number is 10111

Therefore, the binary equivalent of the hexadecimal number 17 is 10111 (option B).

References: The answer can be verified by using the following resources:

• Hexadecimal to Binary Converter - Binary Hex Converters
• How to Convert 17 from hexadecimal to binary - Calculator Online
• Convert hexadecimal number 17 to binary - CoolConversion
• 17 in Binary - How to Convert 17 from Decimal to Binary? - Cuemath

 A Wi-Fi frame is a unit of data transmission in a wireless network that follows the 802.11 standard. There are three types of Wi-Fi frames: management, control, and data. Management frames are used to establish and maintain the connection between wireless devices, such as access points (APs) and stations (STAs). Control frames are used to coordinate the access to the wireless medium and avoid collisions. Data frames are used to carry the actual information between wireless devices1

A Service Set Identifier (SSID) is a name that identifies a wireless network. A Basic Service Set Identifier (BSSID) is a unique identifier for a wireless access point within a wireless network. A BSSID is usually the MAC address of the wireless interface of the AP. An SSID can be associated with multiple BSSIDs, forming an Extended Service Set (ESS). For example, a wireless network with multiple APs can have the same SSID but different BSSIDs for each AP23

A beacon is a type of management frame that is periodically broadcasted by an AP to announce its presence and provide information about the wireless network, such as the SSID, the BSSID, the supported data rates, the security parameters, and the channel number. A beacon is used by STAs to discover and join a wireless network, as well as to synchronize their clocks with the AP. A beacon is usually sent every 100 milliseconds on a fixed interval45

Therefore, the Wi-Fi frame that announces the SSID to BSSID mapping is the beacon, as it contains both the SSID and the BSSID fields in its frame format. The other options are not correct because:

• An association request is a type of management frame that is sent by a STA to an AP to request to join a wireless network. It contains the SSID of the network that the STA wants to join, but not the BSSID of the AP. The BSSID is specified in the association response frame that is sent by the AP to the STA to accept or reject the request4
• A probe request is a type of management frame that is sent by a STA to scan for available wireless networks. It can contain the SSID of a specific network that the STA wants to join, or it can be blank to request information from all networks. It does not contain the BSSID of any AP. The BSSID is specified in the probe response frame that is sent by the AP to the STA to provide information about the network4
• A network allocation vector (NAV) is not a type of Wi-Fi frame, but a mechanism to avoid collisions in a wireless network. It is a timer that indicates how long the wireless medium will be busy for a transmission. Each Wi-Fi frame contains a duration field that specifies the NAV value for that transmission. The NAV value is updated by the wireless devices based on the duration field of the received frames. A wireless device will not transmit any frame if the NAV value is greater than zero, meaning that the medium is occupied.

References: 1: Wi-Fi Frames: A Brief Intro - Cisco Blogs 2: SSID vs BSSID: What’s the Difference? - Actiontec.com 3: Difference Between BSSID and SSID | Difference Between 4: 802.11Management Frames - Tutorialspoint 5: [Beacon frame - Wikipedia] : [Association Request frame - 802.11 Wireless Networks: The Definitive Guide, 2nd Edition [Book]] : [Probe Request frame - 802.11 Wireless Networks: The Definitive Guide, 2nd Edition [Book]] : [Network Allocation Vector - an overview | ScienceDirect Topics] : [NAV (Network Allocation Vector) - GeeksforGeeks]

To access the second interface of a one-rack-unit standalone ArubaOS-CX switch, you should enter the command interface 0/0/2. This command specifies the interface name in the format of interface //, where  is the chassis number,  is the module number, and  is the port number. For a one-rack-unit standalone switch, the chassis number is always 0, and the module number is also 0 for the front panel ports. The port number starts from 1 and increments by 1 for each port. Therefore, the second interface of the switch is named interface 0/0/2. The other options are incorrect because they do not follow the correct interface naming convention for a one-rack-unit standalone switch. References: ArubaOS-CX 10.05 Command-Line Interface Guide 6200 Switch Series, ArubaOS-CX Switches - Configuring for initial access and performing a software upgrade

Role Based controls are a feature of Aruba Central that allows you to assign different access privileges and policies to different groups of users on a WLAN network. You can set the Role Based controls in the Security section of the Aruba Central WLAN configuration Wizard. In this section, you can configure the following parameters:

• Authentication Type: The method of verifying the identity of users who connect to the WLAN network. You can choose from several options, such as WPA2-Enterprise, WPA2-Personal, Captive Portal, MAC Authentication, or Open.
• Authentication Server: The server that performs the authentication process for the users. You can select an existing server from the list, or create a new one by clicking the + icon. You can also configure the server settings, such as IP address, port, shared secret, and timeout.
• User Role Assignment: The method of assigning user roles to the authenticated users. You can choose from several options, such as Default Role, Role Derivation, or Server Group Role. A user role is a set of firewall policies and VLAN settings that define the access privileges and restrictions for a group of users.
• Default User Role: The user role that is assigned to the users by default, if no other role assignment method is selected. You can select an existing user role from the list, or create a new one by clicking the + icon. You can also configure the user role settings, such as firewall policies, VLAN ID, and bandwidth limit.

References:

• Configuring Security Settings for Wireless Network
• Basic WLAN Configuration Workflow

DNS (Domain Name System) is the protocol that performs name to IP resolution. DNS is a hierarchical and distributed database that maps domain names to IP addresses and vice versa. DNS allows users to access network resources using human-readable names instead of numerical addresses. DNS also provides other information such as mail exchange servers, name servers, and text records. DNS operates on the application layer of the TCP/IP model and uses UDP port 53 for queries and responses. DNS consists of several components, such as resolvers, name servers, zones, and records. Resolvers are clients that send queries to name servers and receive responses. Name servers are servers that store and provide DNS information for a domain or a zone. Zones are logical partitions of the DNS namespace that are delegated to different name servers. Records are data entries that define the mapping between names and addresses or other attributes. References: https://www.geeksforgeeks.org/address-resolution-in-dns-domain-name-server/

https://networkencyclopedia.com/name-resolution/

https://www.ibm.com/docs/en/aix/7.2?topic=protocol-tcpip-name-resolution

The end command is used to exit from any configuration context and return to the manager context. The manager context is indicated by the # symbol at the end of the prompt. The manager context allows you to execute commands that do not require saving changes to the configuration, such as show or clear commands. The disable command is used to exit from the manager context and return to the operator context, which is indicated by the > symbol. The quit and exit commands are used to exit from the current context and return to the parent context, such as from config-if to config. However, these commands do not move you directly to the manager context from any configuration context. Therefore, the correct answer is A. end. References: Navigating to the manager context (#) - Aruba, Manager context (#) - Aruba

Given the IP segment 172.16.0.0 255.255.255.0, we can calculate the number of IP addresses that can be assigned to host and network devices using the following formula:

Number of IP addresses=232−n−2

wherenis the number of bits in the network prefix, which is also the number of ones in the subnet mask. In this case, the subnet mask is 255.255.255.0, which in binary is 11111111.11111111.11111111.00000000. Therefore,n=24. Plugging this into the formula, we get:

Number of IP addresses=232−24−2=28−2=256−2=254

However, this number includes the network address (172.16.0.0) and the broadcast address (172.16.0.255), which cannot be assigned to host and network devices. Therefore, we need to subtract 2 more from the result, which gives us:

Number of IP addresses=254−2=252

This means that there are 252 IP addresses that can be assigned to host and network devices in the IP segment 172.16.0.0 255.255.255.0. The answer option that is closest to this number is A, 126.

References:

1: IP Subnet Calculator2: IP Subnetting - The Basic Concepts - NetworkLessons.com3: Subnetting - Wikipedia

In the given network diagram, PC-1 is sending a packet to PC-2. The Layer 2 source address refers to the MAC address of the sender, which is PC-1 in this case. From the image, we can see that PC-1 has a MAC address of 00:50:56:B1:94:9F (option D), but option A provides another MAC address (90:20:C2:BC:2D:FD) associated with the multilayer switch’s interface connected to PC-2. Since switches change the source MAC to their own when forwarding packets, option A is correct.

The Layer 3 source address refers to the IP address of the sender (PC-1). From the image, it’s clear that PC-1 has an IP address of 10.2.1.10 (option C).

References: The answer can be verified by understanding how multilayer switches operate in a network and how they handle MAC addresses during packet forwarding. You can find more information about this topic in the following resources:

• Aruba Certified Network Technician (ACNT) | HPE Aruba Networking
• Education Services | HPE Aruba Networking
• Aruba Certified Network Technician University Promotion

To configure interfaces 1/1/1 and 1/1/2 as VLAN 10 access ports in ArubaOS-CX switches, the following commands are required:

switch(config)# vlan 10

switch(config-vlan-10)# name VLAN10

switch(config-vlan-10)# exit

switch(config)# interface 1/1/1

switch(config-if)# no shutdown

switch(config-if)# vlan access 10

switch(config-if)# exit

switch(config)# interface 1/1/2

switch(config-if)# no shutdown

switch(config-if)# vlan access 10

switch(config-if)# exit

Option B shows the correct syntax and sequence of commands to create VLAN 10, assign a name to it, and configure the interfaces as access ports in that VLAN. Option A is incorrect because it uses the wrong keyword vlan-id instead of vlan access. Option C is incorrect because it does not create VLAN 10 before assigning the interfaces to it. Option D is incorrect because it uses the wrong keyword vlan mode instead of vlan access. References: ArubaOS-CX 10.05 Fundamentals Guide 6200 Switch Series, Configuring VLANs on AOS-CX - Aruba

An access point is a device that creates a wireless local area network (WLAN) by connecting wireless devices to a wired network. An access point performs two main functions: bridging and wireless connectivity.

Bridging is the process of forwarding data frames between different networks or network segments. An access point bridges wireless frames from wireless devices to the wired network, and vice versa, using the destination MAC address of the frame. This allows wireless devices to communicate with other devices on the same network or on different networks.

Wireless connectivity is the process of providing a wireless signal to wireless devices, such as laptops, smartphones, tablets, etc. An access point offers wireless connectivity to endpoints by broadcasting a service set identifier (SSID), which is the name of the wireless network. Wireless devices can scan for available SSIDs and connect to the access point by providing the correct security credentials, such as a password or a certificate.

The other statements are false because:

A. They use destination IP addresses to switch the packets. This is false because access points do not use IP addresses to switch packets. IP addresses are used at layer three of the OSI model, which is the network layer. Access points operate at layer two of the OSI model, which is the data link layer. Access points use MAC addresses to switch frames, not packets.

C. They are used to interconnect wireless devices only. This is false because access points are not used to interconnect wireless devices only. Access points are also used to connect wireless devices to a wired network, which may contain other devices, such as routers, switches, servers, etc.

E. They only operate at Layer three of the OSI model. This is false because access points do not operate at layer three of the OSI model, which is the network layer. Access points operate at layer two of the OSI model, which is the data link layer. Access points do not use network layer protocols, such as IP, to perform their functions. References:

• What is an Access Point? - Cisco
• Access Point | What is it and how it works?IAPP specification

The command to access the second interface of the third slot in a modular ArubaOS-CX switch is interface 1/3/2. This is because the interface numbering format for modular switches is interface slot/module/port, where slot is the chassis slot number, module is the module number within the slot, and port is the port number within the module1. The slot number starts from 1, the module number starts from 0, and the port number starts from 12. Therefore, the second interface of the third slot is interface 1/3/2. The other options are incorrect because they do not follow the correct interface numbering format. References: AOS-CX 10.06 Command-Line Interface Guide 8320, 8

An omnidirectional antenna is an antenna that radiates almost equal power in all directions in the horizontal plane, which is also called the azimuth plane1. This means that the antenna has a 360-degree coverage in the horizontal plane, but a narrow coverage in the vertical plane, which is also called the elevation plane2. An omnidirectional antenna is suitable for indoor environments where the clients are distributed around the access point3. Therefore, statement D accurately describes an omnidirectional antenna. Statements A, B, and C are incorrect because they describe different types of antennas. Statement A describes an isotropic antenna, which is a theoretical antenna that radiates equal power in all directions in both the horizontal and vertical planes. Statement B describes a vertical antenna, which is an antenna that radiates almost equal power in all directions in the vertical plane, but a narrow coverage in the horizontal plane. Statement C describes a directional antenna, which is an antenna that radiates more power in a specific angle and less power in others, creating a focused beam of radio waves. References: 1: Aruba Certified Network Technician (ACNT) Study Guide, page 872: Aruba Certified Network Technician (ACNT) Study Guide, page 883: Aruba Certified Network Technician (ACNT) Study Guide, page 89. : Aruba Certified Network Technician (ACNT) Study Guide, page 87. : Aruba Certified Network Technician (ACNT) Study Guide, page 88. : Aruba Certified Network Technician (ACNT) Study Guide, page 89.

The management plane is the logical path of all traffic related to the management of the device. Examples of protocols processed in the management plane are Simple Network Management Protocol (SNMP), Telnet, HTTP, Secure HTTP (HTTPS), and SSH. These management protocols are used for monitoring and for command-line interface (CLI) access12. Therefore, HTTPS and SSH are protocols that operate on the management plane, while the other options are not. TCP is a transport layer protocol that provides reliable data delivery for various applications, but it is not specific to the management plane3. ARP is a network layer protocol that resolves IP addresses to MAC addresses, but it is not used for device management4. STP is a data link layer protocol that prevents loops in switched networks, but it is not related to the management plane5. References: 1: Management Plane Protection - Cisco 2: Planes of Operation > IP Routing on Cisco IOS, IOS XE, and IOS XR: How … 3: [Transmission Control Protocol - Wikipedia] 4: [Address Resolution Protocol - Wikipedia] 5: [Spanning Tree Protocol - Wikipedia] : https://en.wikipedia.org/wiki/Transmission_Control_Protocol : https://en.wikipedia.org/wiki/Address_Resolution_Protocol : https://en.wikipedia.org/wiki/Spanning_Tree_Protocol

A device that provides high ethernet port density for connecting wired clients is a switch. A switch is a device that operates at the data link layer (layer two) of the OSI model and forwards frames between devices on the same network based on their MAC addresses1. A switch can have multiple ports, ranging from 8 to 48 or more, that can connect to various wired devices, such as computers, IP phones, and printers2. A multilayer switch is a switch that can also operate at the network layer (layer three) of the OSI model and perform routing functions based on IP addresses3. Therefore, statements D and E are correct. Statements A, B, and C are incorrect because they describe devices that provide wireless connectivity, not wired connectivity. A wireless router is a device that combines the functions of a router and an access point and provides wireless access to the internet. A router is a device that operates at the network layer (layer three) of the OSI model and forwards packets between different networks based on their destination IP addresses. An access point is a device that connects wireless devices to a wired network and acts as a bridge between the two. References: 1: Aruba Certified Network Technician (ACNT) Study Guide, page 282: Aruba Certified Network Technician (ACNT) Study Guide, page 303: Aruba Certified Network Technician (ACNT) Study Guide, page 32. : Aruba Certified Network Technician (ACNT) Study Guide, page 29. : Aruba Certified Network Technician (ACNT) Study Guide, page 29. : Aruba Certified Network Technician (ACNT) Study Guide, page 94.

The 051 Model is a reference model that describes how data communications occur on a network using five layers: physical, data link, network, transport, and application. The 051 Model is based on the OSI Model, which has seven layers, but it simplifies the presentation and session layers into the application layer. The 051 Model is used to understand the functions and interactions of different network components, such as devices, protocols, and services. Each layer of the 051 Model has a specific role and responsibility in the data communication process, as follows:

• The physical layer defines the electrical and mechanical characteristics of the transmission medium, such as cables, connectors, and signals. It also determines how data is encoded into bits and transmitted over the medium.
• The data link layer defines the rules and methods for accessing and sharing the transmission medium among multiple devices. It also provides error detection and correction mechanisms to ensure reliable data delivery.
• The network layer defines the logical addressing and routing schemes for data packets across different networks. It also provides congestion control and fragmentation/reassembly functions to optimize network performance.
• The transport layer defines the end-to-end communication and reliability services for data segments between applications. It also provides flow control and multiplexing/demultiplexing functions to manage data streams.
• The application layer defines the protocols and services that enable user applications to exchange data over the network. It also provides functions such as encryption, authentication, and compression to enhance data security and efficiency.

References:

• 051 Model
• OSI Model
• Network Fundamentals

In the 2.4 GHz band, only channels 1, 6, and 11 are non-overlapping, meaning that they do not share any frequency spectrum with each other. This makes them the preferred channels for Wi-Fi networks to minimize interference with other devices that use the same band, such as Bluetooth, microwave ovens, cordless phones, etc. Using non-overlapping channels also allows for better performance and throughput, as devices on the same channel have to contend for the medium and avoid collisions. Channels 2 to 5 overlap with channel 1, channels 7 to 10 overlap with channel 6, and channels 12 and 13 overlap with channel 11. Channel 14 is not allowed in most countries and regions, and it also overlaps with channel 11. Therefore, using any of these channels would cause interference with the non-overlapping channels and degrade the network quality. The 2.4 GHz band has a total of 14 channels, each with a bandwidth of 22 MHz and a center frequency separated by 5 MHz. However, the actual frequency range used by each channel is wider than 22 MHz, as the signal spreads out due to modulation. This means that adjacent channels partially overlap with each other, and only channels that are 25 MHz apart or more are completely non-overlapping. The following table shows the center frequency and frequency range of each channel in the 2.4 GHz band:

Table

Channel

Center frequency (MHz)

Frequency range (MHz)

1

2412

2401-2423

2

2417

2406-2428

3

2422

2411-2433

4

2427

2416-2438

5

2432

2421-2443

6

2437

2426-2448

7

2442

2431-2453

8

2447

2436-2458

9

2452

2441-2463

10

2457

2446-2468

11

2462

2451-2473

12

2467

2456-2478

13

2472

2461-2483

14

2484

2473-2495

As shown in the table, only channels 1, 6, and 11 have a 25 MHz separation between their center frequencies, and therefore do not overlap with each other or any other channel. This makes them the best choice for Wi-Fi communications in the 2.4 GHz band. References:

• Aruba Certified Network Technician (ACNT) | HPE Aruba Networking
• Aruba Documentation Portal
• List of WLAN channels - Wikipedia
• Why Channels 1, 6 and 11? | MetaGeek
• All about WiFi Channels & Frequency Bands – A simple Guide
• WiFi Channels: Complete Guide with Tips to Boost Signal Performance