HPE6-A85 Aruba Certified Campus Access Associate Exam Questions and Answers

When generating a Multiple Pre-Shared Key (MPSK) for headless devices using the ClearPass self-service registration page, the MAC address of the device is required. MPSK associates a unique PSK with the MAC address of a device, providing a way to authenticate devices that may not have a user interface.

The advantage of Layer 2 MAC authentication is that it does not require any setup or configuration on the client device. The network devices (like switches or access points) perform the authentication automatically based on the MAC address of the device when it tries to connect to the network.

The administrative distance is used as a trust rating for route entries (B). It is a metric used by routers to select the best path when there are two or more different routes to the same destination from two different routing protocols. The lower the administrative distance value, the more trustworthy the source of the route. For example, a directly connected network has an administrative distance of 0 because it is the most trusted source of routing information. In contrast, routes learned from different routing protocols have higher administrative distances, reflecting their relative trustworthiness.

a) Alerts on config changes via email - Foundation b) Group-based firmware compliance - Foundation c) Heat maps of deployed APs - Advanced d) Live upgrades of an AOS10 cluster - Advanced

According to the Aruba Central Licensing Guide1, the Foundation License provides basic device management features such as configuration, monitoring, alerts, reports, firmware management, etc. The Advanced License provides additional features such as AI insights, WLAN services, NetConductor Fabric, heat maps, live upgrades, etc.

https://www.arubanetworks.com/techdocs/central/2.5.3/content/pdfs/licensing-guide.pdf

In the context of the OSI model, the network layer is responsible for packet forwarding including routing through intermediate routers. Hence, the network layer PDU is known as a packet.

OAlOps is a feature of Aruba Central that uses artificial intelligence and machine learning to identify recommended steps to resolve network health issues and allows you to share detailed information with support personnel. OAlOps provides insights into network performance, root cause analysis, anomaly detection, proactive alerts, and automated remediation actions. OAlOps also integrates with Aruba User Experience Insight (UXI) sensors to measure and improve user experience across wired and wireless networks. References:https://www.arubanetworks.com/assets/ds/DS_ArubaCentral.pdf

To regain access to an Aruba CX switch when credentials are unknown or lost, one can press and hold the clear button, then power cycle the switch to reset the password. Additionally, using the boot profile 0 at the boot loader menu can be used to bypass the current startup configuration, which may include the unknown credentials.

Using the provided topology and show command output, it can be determined that L3-SW-2 in the Branch Office does not have a route to reach the subnet where PC1 resides (192.168.1.0/24 in the HQ Office). L3-SW-1 in the HQ Office has a route to the Branch Office subnet (172.16.1.0/24), but without the reciprocal route on L3-SW-2, traffic from the Branch Office will not be able to reach the HQ Office subnet, hence PC1 cannot ping PC2.

The best technology to use for dropping excessive broadcast traffic on ingress to an ArubaOS-CX switch is rate limiting. Rate limiting is a feature that allows network administrators to control the amount of traffic that enters or leaves a port or a VLAN on a switch by setting bandwidth thresholds or limits. Rate limiting can be used to prevent network congestion, improve network performance, enforce service level agreements (SLAs), or mitigate denial-of-service (DoS) attacks. Rate limiting can be applied to broadcast traffic on ingress to an ArubaOS-CX switch by using the storm-control command in interface configuration mode. This command allows network administrators to specify the percentage of bandwidth or packets per second that can be used by broadcast traffic on an ingress port. If the broadcast traffic exceeds the specified threshold, the switch will drop the excess packets.

The other options are not technologies for dropping excessive broadcast traffic on ingress because:

DWRR queuing: DWRR stands for Deficit Weighted Round Robin, which is a queuing algorithm that assigns different weights or priorities to different traffic classes or queues on an egress port. DWRR ensures that each queue gets its fair share of bandwidth based on its weight while avoiding starvation of lower priority queues. DWRR does not drop excessive broadcast traffic on ingress, but rather schedules outgoing traffic on egress.

QoS shaping: QoS stands for Quality of Service, which 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 shaping is a technique that delays or buffers outgoing traffic on an egress port to match the available bandwidth or rate limit. QoS shaping does not drop excessive broadcast traffic on ingress, but rather smooths outgoing traffic on egress.

Strict queuing: Strict queuing is another queuing algorithm that assigns different priorities to different traffic classes or queues on an egress port. Strict queuing ensures that higher priority queues are always served before lower priority queues regardless of their bandwidth requirements or weights. Strict queuing does not drop excessive broadcast traffic on ingress, but rather schedules outgoing traffic on egress.

References: https://en.wikipedia.org/wiki/Rate_limiting https://www.arubanetworks.com/techdocs/AOS-CX_10_08/NOSCG/Content/cx-noscg/qos/storm-control.htm https://www.arubanetworks.com/techdocs/AOS-CX_10_08/NOSCG/Content/cx-noscg/qos/dwrr.htm https://www.arubanetworks.com/techdocs/AOS-CX_10_08/NOSCG/Content/cx-noscg/qos/shaping.htm https://www.arubanetworks.com/techdocs/AOS-CX_10_08/NOSCG/Content/cx-noscg/qos/strict.htm

To provide an LACP connection with the maximum available bandwidth, one should configure a link aggregation group (LAG) using all available ports that can be used for data transfer. Since the SFP56 portsare used for stacking, the next best option is to use the 2 SFP28 ports and as many SmartRate 5G (SR5) ports as possible on each switch, which would allow for a 16-member LAG, with 2 SFP28 and 6 SR5 ports on each switch contributing to the LAG.

ICMP (Internet Control Message Protocol) is used by network devices to send error and operational information related to IP communications. It is used to send messages like "destination unreachable" or "time exceeded" when there are issues in IP communication

The main characteristic of the 6 GHz band that is true among the given options is that in North America, the 6 GHz band offers more 80 MHz channels than there are 40 MHz channels in the 5 GHz band. This characteristic provides more spectrum availability, less interference, and higher throughput for wireless devices that support Wi-Fi 6E Wi-Fi Enhanced (Wi-Fi 6E) is an extension of Wi-Fi 6 (802.11ax) standard that operates in the newly available unlicensed frequency spectrum around 6 GHz in addition to existing bands below it. Some facts about this characteristic are:

In North America, there are up to seven non-overlapping channels available in each of three channel widths (20 MHz, 40 MHz, and 80 MHz) in the entireunlicensed portion of the new spectrum (5925–7125 MHz). This means there are up to 21 non-overlapping channels available for Wi-Fi devices in total.

In comparison, in North America, there are only nine non-overlapping channels available in each of two channel widths (20 MHz and 40 MHz) in the entire unlicensed portion of the existing spectrum below it (2400–2483 MHz and 5150–5825 MHz). This means there are only up to nine non-overlapping channels available for Wi-Fi devices in total.

Therefore, in North America, there are more than twice as many non-overlapping channels available in each channel width in the new spectrum than in the existing spectrum below it.

Specifically, there are more than twice as many non-overlapping channels available at 80 MHz width (seven) than at 40 MHz width (three) in the existing spectrum below it.

The other options are not true because:

Less RF signal is absorbed by objects in a 6 GHz WLAN: This option is false because higher frequency signals tend to be more absorbed by objects than lower frequency signals due to higher attenuation Attenuation is a general term that refers to any reduction in signal strength during transmission over distance or through an object or medium . Therefore, RF signals in a 6 GHz WLAN would be more absorbed by objects than RF signals in a lower frequency WLAN.

The 6 GHz band is fully backward compatible with existing bands: This option is false because Wi-Fi devices need to support Wi-Fi 6E standard to operate in the new spectrum around 6 GHz . Existing Wi-Fi devices that do not support Wi-Fi 6E standard cannot use this spectrum and can only operate in existing bands below it.

Low Power Devices are allowed for indoor and outdoor usage: This option is false because Low Power Indoor Devices (LPI) are only allowed for indoor usage under certain power limits and registration requirements . Outdoor usage of LPI devices is prohibited by regulatory authorities such as FCC Federal Communications Commission (FCC) is an independent agency of United States government that regulates communications by radio, television, wire, satellite, and cable across United States . However, outdoor usage of Very Low Power Devices (VLP) may be allowed under certain power limits and without registration requirements.

References: https://www.wi-fi.org/discover-wi-fi/wi-fi-certified-6e https://www.wi-fi.org/file/wi-fi-alliance-spectrum-needs-study https://www.cisco.com/c/en/us/products/collateral/wireless/spectrum-expert-wi-fi/prod_white_paper0900aecd807395a9.html https://www.cisco.com/c/en/us/support/docs/wireless-mobility/wireless-lan-wlan/82068-power-levels.html https://www.wi-fi.org/file/wi-fi-alliance-unlicensed-spectrum-in-the-us

Strict queuing is the best scheduling technology for ensuring that voice traffic, which is sensitive to latency, is prioritized above other types of traffic. This method ensures that voice traffic is sent first before other queued traffic, effectively reducing the possibility of delay.

ClientMatch is an Aruba patented technology that helps to move sticky clients—clients that stay connected to an AP even when there are better APs available—to a more appropriate AP. This technology ensures that clients are always connected to the best available AP, optimizing both the client's performance and the overall performance of the wireless network.

The way that STP Spanning Tree Protocol. STP is a network protocol that ensures a loop-free topology for any bridged Ethernet local area network by preventing redundant paths between switches or bridges from creating loops that cause broadcast storms, multiple frame transmission, and MAC table instability. STP creates a logical tree structure that spans all of the switches in an extended network and blocks any redundant links that are not part of the tree from forwarding data packets3. will forward or discard traffic on these ports is as follows:

STP will elect a root bridge among the two switches based on their bridge IDs, which are composed of a priority value and a MAC address. The switch with the lower bridge ID will become the root bridge and will forward traffic on all its ports.

STP will assign a role and a state to each port on both switches based on their port IDs, which are composed of a priority value and a port number. The port with the lower port ID will become the designated port and will forward traffic, while the port with the higher port ID will become the alternate port and will discard traffic.

In this scenario, since both switches have two cables connected between ports 1/1/1 and 1/1/2, there will be two possible paths between them, creating a loop. To prevent this loop, STP will block one of these paths by discarding traffic on one of the ports on each switch.

Assuming that both switches have the same priority value (default is 32768), the switch with the lower MAC address will have the lower bridge ID and will become the root bridge. The root bridge will forward traffic on both ports 1/1/1 and 1/1/2.

Assuming that both ports have the same priority value (default is 128), port 1/1/1 will have a lower port ID than port 1/1/2 on both switches because it has a lower port number. Port 1/1/1 will become the designated port and will forward traffic, while port 1/1/2 will become the alternate port and will discard traffic.

Therefore, the switch with the lower MAC address will discard traffic on one port (port 1/1/2), while the switch with the higher MAC address will also discard traffic on one port (port 1/1/2).

References: 3 https://en.wikipedia.org/wiki/Spanning_Tree_Protocol

The Alerts and Events dashboard displays all types of alerts and events generated for events pertaining to device provisioning, configuration, and user management. You can use the Config icon to configure alerts and notifications for different alert categories and severities1. You can also view the alerts and events in the List view and Summary view2. References: 1 https://www.arubanetworks.com/techdocs/central/latest/content/nms/alerts/configuring-alerts.htm  2 https://www.arubanetworks.com/techdocs/central/latest/content/nms/alerts/viewing-alerts.htm

Multiple Pre-Shared Key (MPSK) is a feature that allows device-specific or group-specific passphrases to securely add headless devices to the WLAN Wireless Local Area Network. WLAN is a wireless computer network that links two or more devices using wireless communication to form a local area network (LAN) within a limited area such as a home, school, computer laboratory, campus, or office building. . MPSK enhances the WPA2 PSK Wi-Fi Protected Access 2 Pre-Shared Key. WPA2 PSK is a method of securing your network using WPA2 with the use of the optional Pre-Shared Key (PSK) authentication, which was designed for home users without an enterprise authentication server. mode by allowing different PSKs for different devices on the same SSID Service Set Identifier. SSID is a case-sensitive, 32 alphanumeric character unique identifier attached to the header of packets sent over a wireless local-area network (WLAN). The SSID acts as a password when a mobile device tries to connect to the basic service set (BSS) — a component of the IEEE 802.11 WLAN architecture. . MPSK passwords can be generated or user-created and are managed by ClearPass Policy Manager12. References: 1 https://blogs.arubanetworks.com/solutions/simplify-iot-authentication-with-multiple-pre-shared-keys/  2 https://www.arubanetworks.com/techdocs/ClearPass/6.8/Guest/Content/AdministrationTasks1/Configuring-MPSK.htm

Virtual Router Redundancy Protocol (VRRP) is a network protocol that provides automatic assignment of available Internet Protocol (IP) routers to participating hosts. VRRP sends its messages over multicast for communication among routers for the election process of the master and advertisement of the virtual IP address.

In the access tracker of ClearPass, after a customer successfully connects to a guest network through a captive portal, the OUTPUT tab should show a role indicating that the user is authenticated, such as "Guest authenticated." This role confirms that the user has passed the authentication process and has been granted access.

The correct way to configure the routable interface for the subnet to be associated with this VLAN is to create an SVI Switched Virtual Interface (SVI) Switched Virtual Interface (SVI) is a virtual interface on a switch that represents a VLAN and provides Layer 3 routing functions for that VLAN . SVIs are used to enable inter-VLAN routing , provide gateway addresses for hosts in VLANs , apply ACLs or QoS policies to VLANs , etc . SVIs have some advantages over physical routed interfaces such as saving interface ports , reducing cable costs , simplifying network design , etc . SVIs are usually numbered according to their VLAN IDs (e.g., vlan 10) and assigned IP addresses within the subnet of their VLANs . SVIs can be created and configured by using commandssuch as interface vlan , ip address , no shutdown , etc . SVIs can be verified by using commands such as show ip interface brief , show vlan , show ip route , etc . in the subnet on the 6300M stack. An SVI is a virtual interface on a switch that represents a VLAN and provides Layer 3 routing functions for that VLAN. Creating an SVI in the subnet on the 6300M stack allows the switch to act as a gateway for the users in that VLAN and enable inter-VLAN routing between different subnets. Creating an SVI in the subnet on the 6300M stack also simplifies network design and management by reducing the number of physical interfaces and cables required for routing.

The other options are not correct ways to configure the routable interface for the subnet to be associated with this VLAN because:

Create a physically routed interface in the subnet on the 6300M stack for each downstream switch: This option is incorrect because creating a physically routed interface in the subnet on the 6300M stack for each downstream switch would require using one physical port and cable per downstream switch, which would consume interface resources and increase cable costs. Creating a physically routed interface in the subnet on the 6300M stack for each downstream switch would also complicate network design and management by requiring separate routing configurations and policies for each interface.

Create an SVl in the subnet on each downstream switch: This option is incorrect because creating an SVI in the subnet on each downstream switch would not enable inter-VLAN routing between different subnets, as each downstream switch would act as a gateway for its own VLAN only. Creating an SVI in the subnet on each downstream switch would also create duplicate IP addresses in the same subnet, which would cause IP conflicts and routing errors.

Create an SVl in the subnet on the 6300M stack, and assign the management address of each downstream switch stack to a different IP address in the same subnet: This option is incorrect because creating an SVI in the subnet on the 6300M stack, and assigning the management address of each downstream switch stack to a different IP address in the same subnet would not enable inter-VLAN routing between different subnets, as each downstream switch would still act as a gateway for its own VLAN only. Creating an SVI in the subnet on the 6300M stack, and assigning the management address of each downstream switch stack to a different IP address in the same subnet would also create unnecessary IP addresses in the same subnet, which would waste IP space and complicate network management.

References: https://www.arubanetworks.com/techdocs/AOS-CX/10.05/HTML/5200-7295/index.html https://www.arubanetworks.com/techdocs/AOS-CX/10.05/HTML/5200-7295/cx-noscg/l3-routing/l3-routing-overview.htm https://www.arubanetworks.com/techdocs/AOS-CX/10.05/HTML/5200-7295/cx-noscg/l3-routing/l3-routing-config.htm

The weakness introduced into WLAN environment when WPA2-Personal is used for security is that PMK Pairwise Master Key (PMK) is a key that is derived from PSK Pre-shared Key (PSK) is a key that is shared between two parties before communication begins , which are both fixed. This means that all users who know PSK can generate PMK without any authentication process. This also means that if PSK or PMK are compromised by an attacker, they can be used to decrypt all traffic encrypted with PTK Pairwise Temporal Key (PTK) is a key that is derived from PMK, ANonce Authenticator Nonce (ANonce) is a random number generated by an authenticator (a device that controls access to network resources, such as an AP), SNonce Supplicant Nonce (SNonce) is a random number generated by supplicant (a device that wants to access network resources, such as an STA), AA Authenticator Address (AA) is MAC address of authenticator, SA Supplicant Address (SA) is MAC address of supplicant using Pseudo-Random Function (PRF). PTK consists of four subkeys: KCK Key Confirmation Key (KCK) is used for message integrity check, KEK Key Encryption Key (KEK) is used for encryption key distribution, TK Temporal Key (TK) is used for data encryption, MIC Message Integrity Code (MIC) key. .

The other options are not weaknesses because:

It uses X 509 certificates generated by a Certification Authority: This option is false because WPA2-Personal does not use X 509 certificates or Certification Authority for authentication. X 509 certificates and Certification Authority are used in WPA2-Enterprise mode, which uses 802.1X and EAP ExtensibleAuthentication Protocol (EAP) is an authentication framework that provides support for multiple authentication methods, such as passwords, certificates, tokens, or biometrics. EAP is used in wireless networks and point-to-point connections to provide secure authentication between a supplicant (a device that wants to access the network) and an authentication server (a device that verifies the credentials of the supplicant). for user authentication with a RADIUS server Remote Authentication Dial-In User Service (RADIUS) is a network protocol that provides centralized authentication, authorization, and accounting (AAA) management for users who connect and use a network service .

The Pairwise Temporal Key (PTK) is specific to each session: This option is false because PTK being specific to each session is not a weakness but a strength of WPA2-Personal. PTK being specific to each session means that it changes periodically during communication based on time or number of packets transmitted. This prevents replay attacks and increases security of data encryption.

It does not use the WPA 4-Way Handshake: This option is false because WPA2-Personal does use the WPA 4-Way Handshake for key negotiation. The WPA 4-Way Handshake is a process that allows the station and the access point to exchange ANonce and SNonce and derive PTK from PMK. The WPA 4-Way Handshake also allows the station and the access point to verify each other’s PMK and confirm the installation of PTK.

References: https://en.wikipedia.org/wiki/Wi-Fi_Protected_Access#WPA_key_hierarchy_and_management https://www.cwnp.com/wp-content/uploads/pdf/WPA2.pdf

To troubleshoot an Aruba CX 6200 switch that is failing to boot correctly, accessing the switch via the RJ-45 console port on any of its member switches provides direct access to the switch's console for troubleshooting. This method allows a network technician to interact with the boot process, view boot messages, and access boot options, including the selection of different OS images or ServiceOS for recovery purposes.

Proves knowledge of the PMK

Exchanges messages for generating PTK

Distributes an encrypted GTK to the client

Sets first initialization vector (IV)

On an Aruba CX 6300M switch, routing between Switch Virtual Interfaces (SVIs) is enabled by default. Therefore, traffic between SVIs, like 120 and 130, can be routed internally without the need for additional configuration such as route leaking or static routes, as long as there is no 'no routing' configuration present on the SVIs.

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

The dBm is a logarithmic unit of power relative to 1 milliwatt (mW). -20 dBm means that the signal strength is 20 decibels lower than 1 mW. In terms of mW, this is 0.01 mW. Each 10 dB decrease represents a tenfold decrease in power. Therefore, -20 dBm is10−210−2or 0.01 mW.

The client's broadcast domain in ArubaOS can be set with role-based VLAN overrides within the firewall role settings. This allows for dynamic assignment of VLANs to users based on their role, which determines their level of network access, including their broadcast domain.

The Address Resolution Protocol (ARP) is used to map layer-3 IP addresses to layer-2 MAC addresses. When a device on a network wants to communicate with another device, it uses ARP to find the MAC address that corresponds to the IP address it wishes to communicate with, allowing it to construct a frame for the local network.