HPE3-U01 Exam Dumps : Aruba Certified Network Technician Exam (ACNT)

 The 5 GHz band is a radio frequency band used for Wi-Fi communications. It has a higherdata bandwidth than the 2.4 GHz band, but a shorter range and less penetration through walls. The 5 GHz band is divided into several sub-bands, each with a different set of channels. One of these sub-bands is the U-NII-3 band, which covers the frequency range from 5725 MHz to 5850 MHz. This sub-band contains 24 non-overlapping channels, numbered from 149 to 172. Channels 149 to 161 are part of the 5 GHz band and can be used for Wi-Fi communications. Channels 165 and 169 are restricted to indoor use only, and channel 173 is not allowed in some regions. Channels 12, 13, and 14 are not part of the 5 GHz band, but belong to the 2.4 GHz band, which has a different set of channels and regulations. U-NII-5 is not a valid sub-band name, but a proposed extension of the 5 GHz band to include the frequency range from 5925 MHz to 7125 MHz. This extension is not yet approved or implemented, and therefore not part of the 5 GHz band. References: List of WLAN channels, What’s the Difference Between 2.4 and 5 GHz Wi-Fi (and Which Should I Use)?, What is the difference between 2.4 GHz, 5 GHz, and 6 GHz wireless frequencies?

Broadcast communication is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, using the electromagnetic spectrum (radio waves), in a one-to-many model1. A broadcast message is a message that is sent to all endpoints on the network, regardless of their address or identity2. An example of a broadcast message is an ARP request, which is used to find the MAC address of a device that has a specific IP address3. An ARP request is sent to the broadcast address of the network, which is usually the last address in the subnet (e.g., 192.168.1.255 for a /24 network). All devices on the network receive the ARP request and check if their IP address matches the one in the request. If so, they reply with their MAC address to the sender of the ARP request. If not, they ignore the request4. Therefore, an ARP request is an example of broadcast communication, while the other options are not. A DHCP offer is a message that is sent by a DHCP server to a specific client that requested an IP address5. An ICMP echo is a message that is sent by a device to test the connectivity and latency to another device. An HTTP Get is a message that is sent by a web browser to request a web page from a web server. These messages are not broadcast, but rather unicast, meaning they are sent to a single destination. References: 1: Broadcasting - Wikipedia 2: Broadcast communication network - Wikipedia 3: [Address Resolution Protocol - Wikipedia] 4: [How ARP Works - Cisco] 5: [DHCP - Wikipedia] : [Ping (networking utility) - Wikipedia] : [Hypertext Transfer Protocol - Wikipedia] : : resolution/13718-5.html : : :

ARP is a protocol that maps an IP address to a MAC address, which is the physical address of a device on a network. ARP is necessary because the software address (IP address) of the host or computer connected to the network needs to be translated to a hardware address (MAC address). Without ARP, a host would not be able to figure out the hardware address of another host. ARP works by sending a broadcast message to all devices on the network, asking for the MAC address of the device that has a specific IP address. The device that has that IP address replies with its MAC address, and the sender stores this information in its ARP cache for future use. The sender then uses the MAC address as the destination address of the Layer 2 header that encapsulates the IP packet. The Layer 2 header is also known as the data link layer header, which is responsible for delivering the packet to the correct device on the same network. The Layer 3 header is also known as the network layer header, which is responsible for routing the packet to the correct network. Therefore, the correct answer is C, because ARP is used to discover the destination address of the Layer 2 header that encapsulates IP packets1234 References: What Is Address Resolution Protocol (ARP)? - Fortinet, Address Resolution Protocol - Wikipedia, ARP (Address Resolution Protocol) explained - Study-CCNA, Aruba Certified Network Technician Exam HPE3-U01 Actual Questions