HPE6-A47 Exam Dumps : Designing Aruba Solutions

Jitter is the variation in the delay of packets arriving at the destination. It is caused by network congestion, routing changes, or other factors that affect the transmission quality. Jitter can affect the quality of VoIP calls, as it can cause gaps, distortion, or echo in the audio. According to the Aruba Validated Reference Design for Voice and Video over Wi-Fi, the recommended maximum jitter for VoIP calls is 30 ms. Therefore, a jitter of 100 ms would typically cause a poor experience for users.

The other options are incorrect because:

• A. The packet loss is the percentage of packets that are lost or discarded during transmission. Packet loss can affect the quality of VoIP calls, as it can cause missing or corrupted audio. However, according to the Aruba Validated Reference Design for Voice and Video over Wi-Fi, the recommended maximum packet loss for VoIP calls is 1 percent. Therefore, a packet loss of 0.3 percent would not typically cause a poor experience for users.
• B. The throughput is the amount of data that can be transferred per unit of time. Throughput can affect the quality of VoIP calls, as it determines the bandwidth available for the audio. However, according to the Aruba Validated Reference Design for Voice and Video over Wi-Fi, the typical throughput for VoIP calls is 64 Kbps. Therefore, a throughput of 67 Kbps would not typically cause a poor experience for users.
• C. The latency is the delay between the sender and the receiver of packets. Latency can affect the quality of VoIP calls, as it can cause delays or out-of-sync audio. However, according to the Aruba Validated Reference Design for Voice and Video over Wi-Fi, the recommended maximum latency for VoIP calls is 150 ms. Therefore, a latency of 100 ms would not typically cause a poor experience for users.

References:

• Aruba Validated Reference Design: Voice and Video over Wi-Fi - Chapter 2)
• Aruba Certified Design Professional Official Certification Study Guide (HPE6-A47) - Chapter 7)

 To ensure that wireless voice traffic is properly prioritized for Microsoft Skype for Business, the architect should set up firewall policies and SDN to mark voice on the MCs or MM. Firewall policies are used to classify and prioritize traffic based on the application, user role, device type, and location. SDN is used to integrate with the Skype for Business SDN API, which provides real-time information about voice and video sessions, such as source and destination IP addresses, ports, codecs, and quality metrics. By using firewall policies and SDN, the MCs or MM can dynamically mark voice traffic with the appropriate DSCP values and queue them in the highest priority queue on the wireless and wired network12.

The other options are not sufficient or relevant for ensuring wireless voice traffic prioritization for Skype for Business. Broadcast suppression combined with AirGroup is used to reduce the network overhead and improve the user experience for wireless devices that use multicast or broadcast protocols, such as Apple Bonjour or Microsoft UPnP3. Airtime Fairness set to fair-access is used to balance the airtime usage among clients with different capabilities and data rates, such as 802.11ac and 802.11n4. Voice-aware Layer 3 roaming is used to enable seamless handoff of voice sessions across different subnets without dropping the call5. While these features may enhance the overall wireless performance and reliability, they do not directly prioritize voice traffic for Skype for Business.

References:

• Aruba Validated Reference Design: 802.11ac Networks
• Aruba Validated Reference Design: Skype for Business
• Aruba Validated Reference Design: AirGroup
• Aruba Validated Reference Design: Adaptive Radio Management
• Aruba Validated Reference Design: Voice over Wireless LAN

ClearPass OnConnect is a feature of the ClearPass Policy Manager that allows wired authentication on switches that do not support 802.1X or RADIUS protocols. ClearPass OnConnect uses SNMP to monitor and control the switch ports based on the device profiles and policies defined in ClearPass12. ClearPass OnConnect can provide the following benefits for the customer:

• It can enable wired authentication without requiring any changes to the existing switch infrastructure or the end-user devices. This can save the customer’s budget and time, as well as minimize the network disruption and user impact.
• It can provide visibility and control over the wired devices, such as printers, IoT devices, and laptops, that connect to the network. ClearPass OnConnect can identify the device type, user role, and location, and apply the appropriate access policies based on the customer’s security and compliance requirements. For example, ClearPass OnConnect can allow only authorized devices and users to access certain network resources, or quarantine or block any unknown or non-compliant devices.
• It can integrate with the other components of the Aruba solution, such as the MCs, MMs, APs, AirWave, and ClearPass Guest, to provide a consistent and unified network management and security solution across the wired and wireless networks. For example, ClearPass OnConnect can leverage the device profiles and policies from ClearPass Guest, or share the network health and performance data with AirWave.

Therefore, by explaining this feature, the architect can justify the proposed solution and show how it can meet the customer’s needs and expectations for wired authentication, as well as wireless authentication.

References:

• 1: https://www.arubanetworks.com/techdocs/ClearPass/6.7/PolicyManager/index.htm#CPPM_UserGuide/Admin/OnConnect.htm
• 2: https://www.arubanetworks.com/assets/tg/TB_ClearPass_OnConnect.pdf