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)

The customer wants to use certificates to authenticate user devices, which means that they need a strong and secure method of verifying the identity of the devices that connect to the employee WLAN. The best option for this is to use EAP-TLS instead of PEAP-MSCHAPv2. EAP-TLS stands for Extensible Authentication Protocol-Transport Layer Security, and it is a protocol that uses certificates on both the client and the server side to establish a mutual authentication and a secure channel for data exchange. EAP-TLS is considered the most secure EAP method, as it prevents common attacks such as dictionary attacks, man-in-the-middle attacks, and replay attacks.

The other options are not suitable for the customer requirements:

• Option B is incorrect because TKIP encryption is weaker than AES encryption. TKIP stands for Temporal Key Integrity Protocol, and it is an older encryption method that was designed to replace WEP, which had serious security flaws. However, TKIP also has some vulnerabilities, and it is not recommended for modern WLANs. AES stands for Advanced Encryption Standard, and it is a newer and stronger encryption method that provides better security and performance for WLANs.
• Option C is incorrect because WPA2-PSK is less secure than WPA2-Enterprise. WPA2-PSK stands for Wi-Fi Protected Access 2-Pre-Shared Key, and it is a security mode that uses a common passphrase or key to authenticate all devices that connect to the WLAN. However, this passphrase or key can be easily compromised or shared, and it does not provide individual authentication or encryption for each device. WPA2-Enterprise stands for Wi-Fi Protected Access 2-Enterprise, and it is a security mode that uses a RADIUS server to authenticate each device individually and dynamically generate encryption keys for each session. WPA2-Enterprise provides better security and scalability for WLANs.
• Option D is incorrect because TTLS does not use certificates to authenticate user devices. TTLS stands for Tunneled Transport Layer Security, and it is a protocol that uses certificates only on the server side to establish a secure tunnel for data exchange. The client side can use different methods to authenticate, such as passwords, tokens, or certificates. However, TTLS does not require certificates on the client side, and it is less secure than EAP-TLS.

References:

• ArubaOS 8.5 User Guide)
• ArubaOS 8.5 Security Guide)
• Aruba Certified Design Professional Official Certification Study Guide (HPE6-A47))

 A metal firewall is a significant RF obstacle that can be difficult to see visually and might require access to blueprints. A metal firewall is a type of fire-resistant barrier that is made of metal or metal-clad materials and is used to separate different sections of a building or a network. A metal firewall can block or attenuate RF signals that pass through it, causing coverage gaps, signal degradation, or interference in the wireless deployment. A metal firewall can also reflect RF signals, creating multipath fading or distortion in the wireless environment. Therefore, an architect needs to identify the location and thickness of any metal firewalls in the building and account for their impact on the RF design. A metal firewall may require additional access points, antennas, or cabling to provide adequate coverage and performance across the wireless deployment. A metal firewall may also affect the channel planning, transmit power settings, and antenna orientation of the access points and radios. A metal firewall can be difficult to see visually, as it may be hidden behind walls, ceilings, or floors, or blended with other materials.Therefore, an architect might need access to blueprints or other sources of information to locate and measure any metal firewalls in the building. References:

• RF Design | Validated Solution Guide - Aruba
• Managing and Optimizing RF Spectrum for Aruba WLANs | PDF - SlideShare
• RF Optimization - Aruba
• Advanced RF Design & Troubleshooting | PPT - SlideShare