ACSP: Aruba Certified Switching Professional Interview Questions

Passing the ACSP: Aruba Certified Switching Professional certification exam proves that you have the knowledge and skills to implement and operate switching solutions at an enterprise level. And to pass the final hurdle, that is the interview, and grab your desired job, you’ll need to prove your proficiency in configuring and managing modern, open standards-based networking solutions in medium-to-large enterprise networks utilizing international networking technologies. You can also refer to the ACSP: Aruba Certified Switching Professional online tutorial for a good revision of concepts and other preparation resources. 

Interviewing for a job is hard work. But answering the usual questions is even harder. While you can’t know everything they’ll ask you, there are a few questions that come up with almost every new job opportunity, and knowing your responses in advance can help put your mind at ease before the interview even starts. So below is a list of top ACSP: Aruba Certified Switching Professional interview questions for this purpose. Let’s begin!

Top ACSP: Aruba Certified Switching Professional Interview Questions

What is the purpose of ArubaOS?

ArubaOS is the operating system used by Aruba Networks, a subsidiary of HPE, for its wireless access points and network switches. The purpose of ArubaOS is to provide a centralized management platform for configuring, monitoring, and maintaining wireless networks and wired networks.

ArubaOS includes features such as automatic wireless access point discovery, real-time network monitoring, fast roaming, security protocols, network access control, and network-wide configuration management. The operating system also integrates with Aruba’s network management and analytics platforms, allowing for centralized management and analysis of network performance, security, and user behavior.

The primary purpose of ArubaOS is to simplify the management of enterprise-level network infrastructure and to provide a secure, reliable, and scalable platform for delivering high-performance network services.

How does ArubaOS ensure security on switches?

ArubaOS provides several security features to ensure the security of switches in a network. Some of these features include:

1. Access control: ArubaOS provides network access control (NAC) mechanisms, such as 802.1X authentication, MAC authentication, and web authentication, to ensure that only authorized devices are granted access to the network.
2. Port security: ArubaOS allows administrators to configure port security, which restricts the number of MAC addresses that can be learned on a switch port and prevents unauthorized devices from connecting to the network.
3. VLAN security: ArubaOS supports Virtual LANs (VLANs) to segment the network into multiple isolated broadcast domains, reducing the risk of unauthorized access and lateral movement within the network.
4. Network segmentation: ArubaOS provides tools for network segmentation, such as Virtual Switching Framework (VSF) and Virtual Switching System (VSS), to isolate different parts of the network and enhance security.
5. Firewall: ArubaOS includes a stateful firewall that can be configured to enforce security policies, such as access control lists (ACLs), to restrict access to specific parts of the network.
6. Encryption: ArubaOS supports encryption technologies, such as WPA2-Enterprise and SSL, to secure communication between devices and the network.

These security features help to ensure that switches in a network are protected from threats such as unauthorized access, tampering, and data theft. By implementing these features, ArubaOS helps to prevent security breaches and maintain the integrity of the network.

What is the role of VLANs in Aruba switch networks?

In Aruba switch networks, Virtual LANs (VLANs) play an important role in network segmentation and organization. VLANs allow administrators to logically separate a single physical network into multiple virtual networks, each with its own broadcast domain.

The role of VLANs in Aruba switch networks can be summarized as follows:

1. Network Segmentation: VLANs allow administrators to segment the network into smaller, more manageable pieces, reducing the risk of unauthorized access and lateral movement within the network. This can also improve network performance by reducing broadcast traffic.
2. Security: VLANs can be used to isolate different types of network traffic, improving security and reducing the risk of unauthorized access to sensitive data.
3. Scalability: VLANs allow administrators to add new devices to the network without having to reconfigure the entire network.
4. Cost Savings: VLANs can be used to reduce the need for additional physical switches, helping to reduce hardware and maintenance costs.
5. Network Management: VLANs allow administrators to more easily manage different parts of the network, including assigning specific policies and configurations to each VLAN.

In Aruba switch networks, VLANs can be configured using ArubaOS, which provides a centralized management platform for configuring, monitoring, and maintaining VLANs across the network. VLANs can be assigned to specific switch ports, and administrators can also configure VLAN tagging to allow devices in different VLANs to communicate with each other. Overall, VLANs play a key role in ensuring the organization, scalability, and security of Aruba switch networks.

Can you explain the concept of Link Aggregation and its benefits?

Link Aggregation (also known as Ethernet bonding) is a networking technology that combines multiple physical network interfaces into a single virtual interface to increase bandwidth, provide redundancy, and balance network traffic. The concept of Link Aggregation is based on the IEEE 802.3ad standard, which defines the Link Aggregation Control Protocol (LACP) for automatically discovering and configuring link aggregation groups.

The benefits of Link Aggregation are:

1. Increased Bandwidth: Link Aggregation allows multiple physical links to be aggregated into a single logical link, providing increased bandwidth and improved network performance. This can be particularly useful in high-bandwidth applications such as video streaming or large data transfers.
2. Redundancy: Link Aggregation provides redundancy by allowing multiple physical links to be combined into a single logical link. If one of the physical links fails, the other links in the aggregation will continue to carry traffic, providing high availability and avoiding network downtime.
3. Traffic Load Balancing: Link Aggregation distributes network traffic evenly across all the physical links in the aggregation, improving network performance and reducing the risk of network congestion.
4. Simplified Network Configuration: Link Aggregation eliminates the need for multiple physical links to be individually configured, reducing network complexity and improving network management.
5. Cost Savings: Link Aggregation can provide cost savings by reducing the need for additional network switches and cabling, and by improving network performance and reliability.

In summary, Link Aggregation provides increased bandwidth, redundancy, traffic load balancing, simplified network configuration, and cost savings, making it an important technology for improving the performance and reliability of networking infrastructure.

What is IRF and how does it work in Aruba switch networks?

IRF (Intelligent Resilient Framework) is a technology developed by Hewlett Packard Enterprise (HPE) for stacking multiple switches together to form a single, virtual switch. IRF works by allowing multiple switches to be logically grouped together and managed as a single entity, providing increased network availability, scalability, and simplified network management.

In Aruba switch networks, IRF provides several benefits, including:

1. High Availability: IRF provides high availability by allowing multiple switches to be configured as a single virtual switch, so that if one switch fails, the other switches in the IRF stack can continue to carry traffic. This provides a highly resilient and reliable network infrastructure.
2. Increased Bandwidth: IRF allows multiple switches to be aggregated into a single virtual switch, providing increased bandwidth and improved network performance. This can be particularly useful in high-bandwidth applications such as video streaming or large data transfers.
3. Simplified Network Configuration: IRF eliminates the need for multiple switches to be individually configured, reducing network complexity and improving network management. This can also reduce the time and effort required for network maintenance and upgrades.
4. Cost Savings: IRF can provide cost savings by reducing the need for additional network switches and cabling, and by improving network performance and reliability.

IRF works by using a virtual control plane that spans across all switches in the IRF stack, allowing the switches to communicate with each other and share configuration and status information. IRF also supports a single management IP address, which allows administrators to manage the entire IRF stack as a single entity.

In Aruba switch networks, IRF can be configured and managed using ArubaOS, which provides a centralized management platform for configuring, monitoring, and maintaining IRF stacks across the network. IRF is an important technology for ensuring the availability, scalability, and manageability of Aruba switch networks.

What is the purpose of Spanning Tree Protocol (STP) and how does it prevent network loops?

Spanning Tree Protocol (STP) is a network protocol that ensures a loop-free topology for Ethernet networks by disabling links that cause loops. The purpose of STP is to prevent network loops and the broadcast storms that result from them, by creating a tree structure that spans all the switches in the network and blocking any redundant paths.

STP operates by electing a root bridge, which is the center of the tree structure, and determining the least cost paths from all other switches to the root bridge. The protocol then blocks all redundant paths by disabling certain switch ports, leaving only a single active path between any two network devices. This eliminates the possibility of loops and ensures that frames are forwarded in a predictable manner, allowing the network to operate efficiently and avoid network failure.

How does Aruba switches handle network traffic and prioritize it?

Aruba switches handle network traffic by using various techniques to prioritize and manage the flow of traffic through the network. These techniques include:

1. Quality of Service (QoS): Aruba switches can prioritize network traffic using QoS policies, which allow administrators to set the priority of different types of traffic, such as voice, video, and data.
2. Link Aggregation: Link Aggregation allows multiple physical links to be combined into a single logical link, providing increased bandwidth and improved reliability.
3. Load balancing: Load balancing distributes network traffic across multiple physical links to ensure that network traffic is evenly distributed and to prevent overloading of any one link.
4. Flow control: Flow control helps prevent network congestion by controlling the rate at which data is transmitted.
5. VLANs: VLANs allow administrators to segment the network into separate virtual networks, providing increased security and isolation of network traffic.
6. Spanning Tree Protocol (STP): STP helps prevent network loops by controlling the flow of network traffic.
7. Access control lists (ACLs): ACLs provide granular control over network traffic by allowing administrators to define policies for incoming and outgoing traffic.

By using these techniques, Aruba switches can effectively handle network traffic and prioritize it based on the specific requirements of the network and its users. This helps ensure that critical applications receive the necessary bandwidth and low latency, while also improving overall network performance and reliability.

Can you describe the different types of switching modes in Aruba switches?

In Aruba switches, there are several types of switching modes that can be used to configure and manage the switch network:

1. Store-and-forward: In this mode, the switch receives the entire frame before forwarding it. This mode provides reliable delivery of frames and helps prevent errors in the network.
2. Cut-through: In this mode, the switch forwards the frame as soon as the destination address is received, without waiting for the entire frame to arrive. This mode provides low latency, but may not be as reliable as store-and-forward.
3. Hybrid: This mode is a combination of store-and-forward and cut-through. In this mode, the switch can switch between store-and-forward and cut-through depending on the type of traffic and network conditions.
4. Flow-based: This mode is similar to cut-through, but it uses flow information to prioritize and manage network traffic. Flow-based switching helps ensure that important traffic is transmitted quickly and efficiently.
5. SAMPLE-based: This mode is similar to store-and-forward, but it uses a portion of the frame, called a sample, to make forwarding decisions. This mode provides reliable delivery of frames and helps prevent errors in the network.

The choice of switching mode depends on the specific requirements and constraints of the network. Network administrators can choose the switching mode that best meets the needs of their network, based on factors such as reliability, latency, and network performance.

What is the role of Quality of Service (QoS) in Aruba switch networks?

In Aruba switch networks, Quality of Service (QoS) plays a crucial role in managing network traffic and ensuring that critical applications receive the necessary bandwidth and low latency.

QoS allows network administrators to prioritize different types of network traffic, such as voice, video, and data, based on their specific requirements and to provide adequate bandwidth to meet those needs. This helps prevent network congestion and ensures that critical applications are not impacted by less important traffic.

By using QoS, Aruba switches can:

1. Allocate bandwidth: Network administrators can allocate bandwidth to different applications and services based on their priority.
2. Control Latency: QoS can help control the delay or latency of network traffic, which is critical for real-time applications like voice and video.
3. Prevent Network Congestion: QoS can prevent network congestion by ensuring that high priority traffic is transmitted before lower priority traffic.
4. Improve network performance: By providing a more predictable network performance, QoS can help improve the overall user experience.

Overall, QoS helps ensure that Aruba switch networks are efficient, reliable, and able to meet the requirements of different types of applications and services.

How does Aruba switches support Power over Ethernet (PoE) and what are its benefits?

Aruba switches support Power over Ethernet (PoE) by providing electrical power over the Ethernet cables to connected devices such as IP phones, wireless access points, and cameras.

The benefits of PoE in Aruba switch networks are:

1. Cost savings: PoE eliminates the need for separate electrical outlets and reduces the cost of installation and maintenance.
2. Convenience: PoE allows for the placement of devices in locations where there is no electrical power available.
3. Increased reliability: PoE reduces the number of cables required for deployment and helps ensure reliable power delivery to the devices.
4. Improved network performance: PoE provides a consistent and reliable power source, ensuring that devices operate optimally and improving network performance.
5. Scalability: PoE makes it easy to add new devices to the network, reducing the time and costs associated with installing new power outlets.

1. What are wired networks?

A wired network is the common type of wired configuration. The most popular wired network connection uses Ethernet cables to transfer data between connected computers. For use in a small wired network, a single router can help connect all the computers. Larger networks often involve multiple routers or switches that connect to each other.

2. Could you elaborate on the advantages of a wired network?

• Stability and Reliability
• Faster Speeds and High Connectivity
• Better Security
• Accessibility
• Inconvenience Due to Lack of Mobility
• May Require More Time to Install
• Larger Infrastructures Require More Maintenance
• Slight Inconvenience Due to Too Many Cables.

3. Could you explain what is Network configuration?

Configuring a network to support the communication of an organization and its network owners is a complex task—a network configuration requires multiple configuration processes on server hardware and software, as well as networking equipment. Network configuration is the process of setting a network’s physical, logical, and operational characteristics in a way that supports the network owner’s overall business plans.

4. What are the layer 2 technologies?

The second layer of the OSI model is called the Logical Link Control and Management (LLC/MAC) sublayer. The LLC is responsible for managing communications links and handling frame traffic, while the MAC governs protocol access to the physical network medium.

5. What does Layer 2 connection mean?

The data link layer of the network, known as Layer 2, is responsible for moving data across the physical links in your network—communication between switches. Capitalize on the high speeds that Layer 2 connectivity provides by installing it on your infrastructure.

6. What is port security and how does it work with a managed switch?

You can secure your network by implementing port security. It prevents any unknown devices from forwarding data packets and thus securing the network. Moreover, it ensures that all the dynamically locked addresses are freed in any unwanted event of a link go-down. Static locking ensures that specific static MAC addresses are associated with a port and dynamic locking enables you to specify how many MAC addresses can be learned on a port.

7. How would you define VLAN?

A virtual local area network is a custom network generated by one or more local area networks. It creates a virtual LAN by combining devices in different networks into one logical network. Virtual Local Area Networks (VLANs) are logical networks generated from one or more physical networks. VLANs consolidate devices from different LANs into one logical network.

8. What are some of the common types of VLAN that you know?

There are three main types of VLANs: port-based, protocol-based, and MAC-based. Port-based VLANs use a port to group virtual area networks; protocol-based VLANs group networks based on a protocol type, and MAC-based VLANs allow Virtual LAN assignment to untagged packets.

9. Could you tell us more about the unicast traffic?

The network switch, which is commonly associated with network learning, comes up with a table that specifies the locations of every device connected to it so that it can direct data to the correct destination. If the network switch has a table of the location of each device, it will not have to waste time locating each device. However, unicast flooding can lead to periods of poor network performance and even total network collapse.

10. Could you tell us some of the functions of a switch?

There are ideally four chief functions of a switch: 

• Firstly, learning the MAC or physical address of a given device on a switch port
• Secondly, framing established a unicast and an unknown unicast
• Then, filtering where the frame is forwarded through a switch port where the switch has learned the MAC address
• Lastly, loop avoidance through spanning tree protocols

11.  What Is MAC address and why is it needed?

A media access control address (MAC address) is a unique identifier that all network devices—wireless or hardwired—must-have. It is written into each network card as a matter of course and cannot be removed or altered. As such, it is responsible for identifying every single device on a given network.

12. Could you differentiate between a hub and a switch?

A hub is basically used as a connection point for several devices in a Local Area Network and works with multiple ports. On the other hand, a switch uses packet switching for receiving and relaying the data within a network. Therefore, it is more efficient and intelligent than the hub.

The chief point of difference between them is in how they deliver the data packets. In this case, a switch can record the addresses of connected devices and then learn each of them, thereby improving the speed of networks.

13. Could you please define ARP and tell us some of the instances when it is required?

The address resolution protocol has come to be known as ARP. It acts as a bridge between the Internet Protocol, or IP, address and the Media Access Control, or MAC, addresses when two devices are connected to a local area network. The MAC address is unique to each device so it helps that these addresses do not differ in length.

14. What is spanning tree protocol? Could you explain from your experience in this field?

 Spanning Tree Protocol, more commonly known as STP, eliminates loops normally caused during transmission while trying to offer several layers of redundancy. It is a link management protocol that reduces the probability of data loss and other problems on the network by creating only one pathway between switches. This protocol facilitates the exchange of information via bridge protocol data units in order to allow for priority handling and recovery mechanisms.

15. Could you differentiate between broadcast and collision domains?

• Unlike the collision domain, the broadcast domain allows the traffic to flow anywhere on the network. Collisions occur in a section of the network where traffic flows back and forth.
• Normal switch failures occur in collision domains, but not in a broadcast domain.
• When a router has multiple broadcast domains, the ports are found in separate broadcast domains, but when the switch or hub has many broadcast domains, all of the ports are found in the same place.
• In collision domains, any IP device can be included, whereas broadcast domains do not allow this.

16. Could you differentiate between static and dynamic VLAN?

Static VLANs—also known as port-based VLANs—are created when an administrator manually assigns a port to a VLAN. In contrast, dynamic VLANs are created when a host connected to a switch through its hardware address is assigned to a VLAN.

The latter solution uses a central server known as the VLAN Membership Policy Server, or VMPS, which is equipped with a database containing the MAC addresses of all devices on the network. Such a server creates a VLAN to MAC address mapping.

17. What do you understand by VLAN Tagging?

Also called frame tagging, it is a method used to identify data packets traveling through trunk lines. A special tag is added to the frame by creating a VPN tag and sending it across the link. When the frame reaches the end of the trunk line, it is stripped of its tag and sent to the appropriate access link.

18. Could you please explain the concept of cut-through LAN switching using your years of switching experience?

When a data frame is received by the router, it immediately retransmits the frame. This is done to forward the frame to a different network segment once it has read its intended destination address. This form of switching is used in complex or highly congested networks and is one of the most intriguing types of switching.

19. What do data pockets consist of?

A data packet has four components: the sender and recipient’s information; the data contained, and an identification number. An identification number, or ID number, is a numeric number that defines both the data packet, or datagram, and its order in the sequence of transactions.

Whenever data is sent across a network, it is converted into packets of data. The packets carry all the necessary information for the message to be properly reconstructed.

20. What is the distinction between LAN, MAN, and WAN?

The LAN, or the Local Area Network, is a computer network device that connects computers inside a certain building or area. It is a high-speed data network connecting workstations, servers, printers, and other information technology equipment within the same building or campus. A good example of a local area network is Ethernet.

MAN, or metropolitan area network, is generally based on multiple buildings within a single city area, unlike LAN, which is built within one building. A good example is the IUB network.

WANs are large-scale networks that link many enterprises or organizations but are not restricted to one. It forges a connection between several LANs. A good example is the internet.

21. How would you differentiate between Unicast, Multicast, Broadcast, and Anycast?

A unicast is a one-to-one information exchange between a single source and a destination. The packets sent are relayed directly to the receiver. A broadcast is one-to-all information exchange among a group of network nodes, with each node receiving a copy of the packet that contains the message.

On the other hand, multicast involves the message exchange between a sender and multiple recipients. In contrast to broadcast, it’s the network configuration that determines which devices receive the data. Lastly, anycast is a method for messaging from one host to another using both TCP and UDP protocols, where a copy of each data packet is sent to the appropriate recipient.

22. What makes ARP different from RARP?

The Address Resolution Protocol (ARP)—orthogonal to the Internet Protocol, or IP—maps an IP address to a physical device. In contrast, the Reverse Address Resolution Protocol (RARP) maps the Media Access Control, or MAC, address to the IP address.

23. What do you understand by an IP address? Could you define what it is?

The Internet protocol address is a 32-bit to 128-bit identifier assigned to any device using the TCP/IP protocol suite. It is usually a unique number or figure that can help identify the connected device and that clearly defines how the device can communicate with other devices on the Internet. There are two versions of IP: IPv4, which is the 32-bit version, and IPv6, which is the 128-bit version.

24. What is your understanding of network congestion?

In-Network congestion, it can happen that a node carries more data than the network can handle. Under these circumstances, packets and information are lost; this means that the receiver cannot get the appropriate information.

25. How would you explain how switches work?

Switches have changed little in the past two decades. They receive signals that tell them which ports to send frames to, and they send those frames according to how the signals are customized for each port. Data packets are usually forwarded between multiple LAN segments as the switch supports packet control whenever data is sent to the Data Link or the network layer of the OSI model.

It is important to note that signals are enabled during packet transmission, which is why they can be accessed during the switch’s analysis of the destination address.

26. What are the different layers of the OSI Model?

The OSI model has seven layers, with each layer specializing in a different area of the model. The first layer is the physical layer, the second is the data link layer, the third is the network layer, and the upper four layers are the transport layer, session layer, presentation layer, and application layer. Furthermore, all of these layers have unique functionalities.

27. Could you explain the function of the application layer regarding networking?

An application layer, which is often referred to as Layer 7, exists between the presentation and transport layers of the OSI reference model. Applet developers sometimes use this network layer to provide network services to communication components beyond those specified in the OSI model.

Expert’s Corner

There’s no substitute for hard work when it comes to preparation. The more practice tests you take, the more familiar you’ll be with the types of questions that will appear on exam day, and the more confident you’ll be when writing your own test. And of course, you’ll be less likely to make the same mistakes as you practice. Remember, Practice makes perfect. So take the ACSP: Aruba Certified Switching Professional Free Practice Tests now!