HP Updated HPE6-A85 Exam Questions and Answers by ajay

A UXI (User Experience Insight) is a device that simulates user behavior and tests network performance from the user perspective. It can check different applications, such as HTTP, VOIP, or Office 365, and measure metrics such as latency, jitter, packet loss, and throughput. References:https://www.arubanetworks.com/products/networking/user-experience-insight/

QoS Quality of Service (QoS) is a set of techniques that manage network resources and provide different levels of service to different types of traffic based on their requirements. QoS can improve network performance, reduce latency, increase throughput, and prevent congestion. concept and its definition. Here is my answer:

QoS Concept:

• Best Effort Service
• Class of Service
• Differentiated Services
• WMM ====================== Definition:

d) A method where traffic is treated equally in a first-come, first-served manner a) A method for classifying network traffic at Layer 2 by marking 802.1Q VLAN Ethernet frames with one of eight service classes b) A method for classifying network traffic at Layer 3 by marking packets with one of 64 different service classes c) A method for classifying network traffic using access categories based on the IEEE 802.11e QoS standard

Short But Comprehensive Explanation of Correct Answer Only: The correct match between QoS concept and its definition is as follows:

• Best Effort Service: This is a method where traffic is treated equally in a first-come, first-served manner without any prioritization or differentiation. This is the default service level for most networks and applications that do not have specific QoS requirements or guarantees. Best Effort Service does not provide any assurance of bandwidth, delay, jitter, or packet loss.
• Class of Service: This is a method for classifying network traffic at Layer 2 by marking 802.1Q VLAN Ethernet frames with one of eight service classes (0 to 7). These service classes are also known as IEEE 802.1p priority values or PCP Priority Code Point (PCP) is a 3-bit field in the 802.1Q VLAN tag that indicates the priority level of an Ethernet frame . Class of Service allows network devices to identify and handle different types of traffic based on their priority levels. Class of Service is typically used in LAN Local Area Network (LAN) is a network that connects devices within a limited geographic area, such as a home, office, or building environments where Layer 2 switching is predominant.
• Differentiated Services: This is a method for classifying network traffic at Layer 3 by marking packets with one of 64 different service classes (0 to 63). These service classes are also known as DiffServ Code Points (DSCP) DiffServ Code Point (DSCP) is a 6-bit field in the IP header that indicates the service class of a packet . Differentiated Services allows network devices to identify and handle different types of traffic based on their service classes. Differentiated Services is typically used in WAN Wide Area Network (WAN) is a network that connects devices across a large geographic area, such as a country or continent environments where Layer 3 routing is predominant.
• WMM: This is a method for classifying network traffic using access categories based on the IEEE 802.11e QoS standard. WMM stands for Wi-Fi Multimedia and it is a certification program developed by the Wi-Fi Alliance to enhance QoS for wireless networks. WMM defines four access categories (AC): Voice, Video, Best Effort, and Background. These access categories correspond to different priority levels and contention parameters for wireless traffic. WMM allows wireless devices to identify and handle different types of traffic based on their access categories.

References: https://en.wikipedia.org/wiki/Quality_of_service https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/qos_dfsrv/configuration/xe-16/qos-dfsrv-xe-16-book/qos-dfsrv-overview.html https://www.cisco.com/c/en/us/support/docs/quality-of-service-qos/qos-packet-marking/10103-dscpvalues.html https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/81831-qos-wlan.html https://www.wi-fi.org/discover-wi-fi/wi-fi-certified-wmm

dBm is a unit of power that measures the ratio of a given power level to 1 mW. The formula to convert dBm to mW is: P(mW) = 1mW * 10^(P(dBm)/10). Therefore, -20 dBm corresponds to 0.01 mW, as follows: P(mW) = 1mW * 10^(-20/10) = 0.01 mW References:https://www.rapidtables.com/convert/power/dBm_to_mW.html

Only: Daisy chain plus MAD and ring are the recommended VSF topologies for Aruba switches. They provide high availability and redundancy for the VSF stack. MAD (Multiple Active Detection) is a mechanism to detect and resolve split-brain scenarios in a VSF stack. References:https://www.arubanetworks.com/techdocs/AOS-CX/10.04/HTML/5200-6790/GUID-D6EF042E-EEEF-49F7-B67E-4CAC41CCB24D.html