HP HPE6-A90 Exam Dumps<\/b><\/a> and Practice Test Dumps<\/b><\/p>\n <\/p>\n
Question: 321. Which protocol is commonly used to synchronize clocks across network devices?<\/b><\/p>\n\n- <\/b> FTP<\/span>
\n<\/span>2.<\/b> NTP<\/span>
\n<\/span>3.<\/b> ARP<\/span>
\n<\/span>4.<\/b> SMTP<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 2. NTP<\/span><\/p>\nExplanation:<\/b><\/p>\n
NTP, or Network Time Protocol, is used to synchronize system clocks across networked devices. Accurate time is important for logging, troubleshooting, authentication, certificates, security monitoring, and event correlation. Network devices can obtain time information from configured NTP servers and adjust their clocks accordingly. FTP is used for file transfers, ARP resolves IPv4 addresses to MAC addresses, and SMTP is used for email transmission. Maintaining consistent time across network infrastructure helps administrators accurately correlate events occurring on different devices.<\/span><\/p>\nQuestion: 322. Which IPv4 address represents the loopback interface?<\/b><\/p>\n\n- <\/b> 127.0.0.1<\/span>
\n<\/span>2.<\/b> 169.254.1.1<\/span>
\n<\/span>3.<\/b> 224.0.0.1<\/span>
\n<\/span>4.<\/b> 192.168.1.1<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 1. <\/span>127.0.0.1<\/span><\/p>\nExplanation:<\/b><\/p>\n
127.0.0.1<\/span> is the commonly used IPv4 loopback address. Traffic sent to this address is processed locally by the host and does not need to travel across a physical network interface. Loopback testing can help determine whether the local TCP\/IP stack is functioning. Addresses in the <\/span>169.254.0.0\/16<\/span> range are commonly associated with link-local addressing, <\/span>224.0.0.0\/4<\/span> is the IPv4 multicast range, and <\/span>192.168.0.0\/16<\/span> is a private address range. Therefore, <\/span>127.0.0.1<\/span> is the loopback address.<\/span><\/p>\nQuestion: 323. What is the primary purpose of a default gateway?<\/b><\/p>\n\n- <\/b> Assign MAC addresses to switches<\/span>
\n<\/span>2.<\/b> Resolve domain names<\/span>
\n<\/span>3.<\/b> Forward traffic toward remote networks<\/span>
\n<\/span>4.<\/b> Encrypt all Ethernet frames<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 3. Forward traffic toward remote networks<\/span><\/p>\nExplanation:<\/b><\/p>\n
A default gateway provides a host with a next-hop router for destinations that are outside the host’s local IP subnet. When a device needs to communicate with a remote network and no more specific route exists, it forwards the traffic to its configured default gateway. The gateway can then route the packet toward its destination. DNS handles name resolution, switches learn MAC addresses, and encryption is provided by separate security mechanisms. A correctly configured default gateway is therefore essential for hosts that need to communicate beyond their local subnet.<\/span><\/p>\nQuestion: 324. Which Ethernet cable type is traditionally used to connect a typical host to a switch?<\/b><\/p>\n\n- <\/b> Rollover cable<\/span>
\n<\/span>2.<\/b> Crossover cable<\/span>
\n<\/span>3.<\/b> Console cable<\/span>
\n<\/span>4.<\/b> Straight-through cable<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 4. Straight-through cable<\/span><\/p>\nExplanation:<\/b><\/p>\n
A straight-through Ethernet cable has traditionally been used to connect unlike device types, such as an end host to a switch. A crossover cable was traditionally used for certain like-device connections, such as switch-to-switch or host-to-host connections, although modern interfaces often support auto-MDI\/MDIX and can automatically accommodate cable differences. Rollover cables are associated with console connections, not ordinary Ethernet data connections. Therefore, for the conventional host-to-switch connection model, a straight-through Ethernet cable is the expected answer.<\/span><\/p>\nQuestion: 325. Which protocol translates domain names into IP addresses?<\/b><\/p>\n\n- <\/b> DNS<\/span>
\n<\/span>2.<\/b> DHCP<\/span>
\n<\/span>3.<\/b> SSH<\/span>
\n<\/span>4.<\/b> SNMP<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 1. DNS<\/span><\/p>\nExplanation:<\/b><\/p>\n
DNS, or Domain Name System, resolves human-readable domain names into IP addresses and can also provide other types of name-related information. For example, a client can query DNS to determine the IP address associated with a website hostname before establishing a connection. DHCP automatically provides network configuration, SSH provides secure remote access, and SNMP is commonly used for network monitoring and management. DNS is therefore the protocol responsible for translating domain names into IP addresses.<\/span><\/p>\nQuestion: 326. Which switch data structure maps learned MAC addresses to switch ports?<\/b><\/p>\n\n- <\/b> Routing table<\/span>
\n<\/span>2.<\/b> DNS cache<\/span>
\n<\/span>3.<\/b> MAC address table<\/span>
\n<\/span>4.<\/b> ARP request queue<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 3. MAC address table<\/span><\/p>\nExplanation:<\/b><\/p>\n
A switch maintains a MAC address table, sometimes called a CAM table, to associate learned source MAC addresses with the ports on which those addresses were observed. When a frame arrives, the switch can use this information to determine where the frame should be forwarded. A routing table is used for Layer 3 forwarding, DNS caches contain name-resolution information, and ARP information associates IPv4 addresses with MAC addresses. Therefore, the MAC address table is the switch structure used to map MAC addresses to ports.<\/span><\/p>\nQuestion: 327. Which IEEE standard is associated with the original 15.4-watt Power over Ethernet implementation commonly known as PoE?<\/b><\/p>\n\n- <\/b> IEEE 802.11ac<\/span>
\n<\/span>2.<\/b> IEEE 802.3af<\/span>
\n<\/span>3.<\/b> IEEE 802.1Q<\/span>
\n<\/span>4.<\/b> IEEE 802.1D<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 2. IEEE 802.3af<\/span><\/p>\nExplanation:<\/b><\/p>\n
IEEE 802.3af defines an early standardized Power over Ethernet implementation that can provide electrical power over Ethernet cabling to compatible powered devices. It is commonly referred to as PoE. Later standards, including 802.3at and 802.3bt, provide higher power levels and additional capabilities. IEEE 802.1Q is associated with VLAN tagging, 802.1D includes traditional bridging and Spanning Tree specifications, and 802.11 standards define wireless LAN technologies. Therefore, IEEE 802.3af is the standard associated with the original PoE implementation.<\/span><\/p>\nQuestion: 328. Which technology allows a Layer 2 switch network to be logically divided into multiple broadcast domains?<\/b><\/p>\n\n- <\/b> NAT<\/span>
\n<\/span>2.<\/b> VLANs<\/span>
\n<\/span>3.<\/b> DNS<\/span>
\n<\/span>4.<\/b> NTP<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 2. VLANs<\/span><\/p>\nExplanation:<\/b><\/p>\n
VLANs, or Virtual Local Area Networks, logically divide a switched network into separate Layer 2 broadcast domains. Devices in different VLANs are logically separated even when they are connected to the same physical switching infrastructure. Communication between VLANs generally requires a Layer 3 device or Layer 3 switching function. NAT translates network addresses, DNS provides name resolution, and NTP synchronizes clocks. VLANs are therefore the technology used to create logical Layer 2 network separation.<\/span><\/p>\nQuestion: 329. Which utility is commonly used to test basic IP reachability between two hosts?<\/b><\/p>\n\n- <\/b> ping<\/span>
\n<\/span>2.<\/b> ftp<\/span>
\n<\/span>3.<\/b> telnet<\/span>
\n<\/span>4.<\/b> netstat<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 1. ping<\/span><\/p>\nExplanation:<\/b><\/p>\n
The <\/span>ping<\/span> utility is commonly used to test basic IP reachability. It normally sends ICMP Echo Request messages and waits for ICMP Echo Reply messages from the destination. Successful responses can indicate that the destination is reachable at the IP layer, although a failed ping does not always prove that a host is completely unavailable because firewalls or security policies may block ICMP. FTP is a file-transfer protocol, Telnet provides remote terminal access, and netstat displays network connection information.<\/span><\/p>\nQuestion: 330. Which device primarily makes forwarding decisions based on Layer 3 IP addresses?<\/b><\/p>\n\n- <\/b> Hub<\/span>
\n<\/span>2.<\/b> Layer 2 bridge<\/span>
\n<\/span>3.<\/b> Router<\/span>
\n<\/span>4.<\/b> Repeater<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 3. Router<\/span><\/p>\nExplanation:<\/b><\/p>\n
A router makes Layer 3 forwarding decisions based primarily on destination IP addresses and information contained in its routing table. It connects different IP networks and determines an appropriate next hop for packets. A traditional hub repeats electrical signals, a Layer 2 bridge or switch primarily forwards Ethernet frames based on MAC addresses, and a repeater regenerates signals. Although modern multilayer switches can also perform Layer 3 routing, the router is the classic network device associated with IP-based forwarding.<\/span><\/p>\nQuestion: 331. Which protocol resolves an IPv4 address to a corresponding MAC address on a local network?<\/b><\/p>\n\n- <\/b> DNS<\/span>
\n<\/span>2.<\/b> ARP<\/span>
\n<\/span>3.<\/b> DHCP<\/span>
\n<\/span>4.<\/b> NTP<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 2. ARP<\/span><\/p>\nExplanation:<\/b><\/p>\n
ARP, or Address Resolution Protocol, is used in IPv4 networks to determine the MAC address associated with a known IPv4 address on the local network. A host can send an ARP request asking which device owns a particular IPv4 address. The device with that address can respond with its MAC address, allowing the sender to construct the appropriate Ethernet frame. DNS resolves names to IP addresses, DHCP provides configuration, and NTP synchronizes clocks. Therefore, ARP performs IPv4-to-MAC address resolution.<\/span><\/p>\nQuestion: 332. Which protocol provides encrypted command-line remote access to a network device?<\/b><\/p>\n\n- <\/b> Telnet<\/span>
\n<\/span>2.<\/b> FTP<\/span>
\n<\/span>3.<\/b> SSH<\/span>
\n<\/span>4.<\/b> TFTP<\/span><\/li>\n<\/ol>\nCorrect Answer:<\/b> 3. SSH<\/span><\/p>\n