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IT asset discovery is a critical part of IT management, allowing organizations to take inventory of all the devices and software used across their networks.
With a comprehensive understanding of an organization’s IT assets, businesses can maximize efficiency and reduce maintenance costs by properly deploying resources, detecting security threats more quickly, and better protecting themselves against data breaches.
Asset discovery allows organizations to map out their entire IT infrastructure—including physical devices such as computers, laptops, routers, switches, firewalls, printers and phones, virtual machines, software, cloud services, and other applications—so they can have better control over the system’s architecture.
Most IT discovery tools use active and passive discovery techniques to create an accurate picture of the assets within an environment to achieve this. With reliable asset discovery data, businesses can maintain security policies and properly budget resources.
In this article, we will discuss the basics of active and passive asset discovery, how they differ, and when to use them.
The differences between active and passive IT discovery
Below we have listed key differentiators between active and passive discovery:
|Key aspects||Active discovery||Passive discovery|
|Scanning process||Scans your network for new items, such as hardware devices or software applications. You can do it manually or through automated scanning tools that map out all existing records in detail. Quickly help detect any unauthorized access and any changes made without consent.||Operates more continuously with no manual intervention required. By monitoring user activity patterns, identify any unknown devices connected to the network and any unauthorized usage of existing assets on the system.|
|Based on historical data||This technique does not rely on historical data to identify assets in your network.||This technique identifies unauthorized assets within the network based on historical data.|
|Configuration requirements||It involves specialized tools to scan devices and systems, which can be intrusive and disruptive to normal operations. For example, IP addresses might change as they may be reassigned at any time due to DHCP or other network changes. It would require additional complexity, such as SNMP polling and frequent asset list refreshes, to prevent a device from being missed or incorrectly identified.||Passive discovery methods do not require any particular configuration or scanning and impact normal operations much less than active discovery.|
|Depth of scanning||Active discovery processes can identify assets in any deployed environment irrespective of whether it generates activity. It uses a ping-and-response process to ping each device or even log into it to obtain the necessary configuration details.||Instead of scanning all assets within the scope of the scan, it can only identify those generating activity at the time of discovery. This means that passive discovery methods will not identify inactive or silent assets.|
|Reliance on active assets||It uses the ping-and-response process, which means that the asset needs to be minimally active to respond to the discovery scanner’s signals.||You can collect information even for those assets that are no longer active or have gone offline due to hardware failure or other problems. Leveraging archived syslog data allows organizations to easily track changes over time to anticipate potential security threats and vulnerabilities better and take proactive measures against them.|
|Network segmentation||Network segmentation involves splitting up parts of a network into smaller sections so that certain types of network traffic are isolated from others. By isolating different parts of the network from each other, organizations can reduce their attack surface by creating fewer viable paths for attackers to exploit system vulnerabilities. As part of an organization’s active asset discovery strategy, they need to understand how their segmentation affects their ability to identify assets across each segmented area.||Passive discovery quickly identifies and catalogs the assets within their environment without having to query each asset individually. It relies on historical data, so it does not necessarily have to account for network segmentation while scanning.|
|Cost requirements||Additionally, this method is usually more expensive due to its need for specialized tools and staff. However, it will discover the full scope of assets within its parameters and create a more accurate asset inventory.||This method requires fewer resources, such as technical expertise and equipment, making it cheaper overall.|
|Level of technical knowledge required||In addition, due to the large amount of data that needs to be evaluated, organizations must have tools and processes that can efficiently capture and process relevant information. It typically requires a certain level of technical knowledge and the ability to configure the scanning software correctly.||This method requires lesser technical expertise as the tool works based on historical data and has standard yet limited capabilities.|
|Impact on service delivery||Active discovery requires more resources and can be more disruptive to operations than passive discovery methods, but it provides a more comprehensive list of discovered assets.||Passive discovery does not need configuration or scanning and has minimal impact on operations. However, it will only identify some assets if they are generating activity at the time of discovery.|
How do you choose the right discovery type?
When deciding between active and passive asset discovery, you must consider your business’s specific needs. If you have a clear idea of what you need to discover, then active discovery is the way. You can target particular areas to get more detailed results. However, if you are starting or exploring new areas, then passive discovery is better as it requires less effort up front.
In addition, when considering which method to use for asset discovery, think about the amount of time you have available for the task. Active discovery requires more effort upfront than passive discovery. On the other hand, passive discovery takes more time as the results are less comprehensive and rely on existing data or require devices to send signals.
The type of data you need to collect should also factor into your decision-making process. Active discovery allows you to pinpoint specific data points. With passive discovery, there is no guarantee that the information being found is accurate or relevant.
Also, if security is a priority for your business, active asset discovery offers better protection against potential data breaches or malicious activity. It does so using built-in monitoring tools that detect any suspicious activity or unauthorized access attempts.
Finally, the cost associated with each type of asset discovery should also come into play when selecting a method. Active asset discovery requires more upfront investments in workforce and technology resources. However, they can often result in faster and more detailed results depending on the complexity of the task.
Passive asset discovery may be cheaper initially but can take longer and have increased potential for errors due to their reliance on luck. However, it is a good option when trying to limit network consumption as it detects traffic being broadcasted around a particular network—but it does need each device to send out a syslog to be able to identify it.
When choosing between active and passive asset discovery, it is essential to evaluate your business needs carefully. Only after that should you make an informed decision that will deliver the best outcomes for your company on time.
Create an accurate inventory of your IT assets with Virima
IT asset discovery tools can be an excellent way to save time and money while maintaining a secure network. Whether you choose passive or active IT asset discovery depends on the needs of your business and how much work you want to put into finding out what is on your network.
We recommend choosing one that offers both options, as different circumstances demand different discovery methods. For example, IT discovery tools like Virima offer both of these options. You can use active scanning methods to identify assets in your network in real-time, whereas passive scanning methods use existing data to determine network assets. While active scanning happens only during scheduled time slots, passive scanning is continuous.
A combination of these methods ensures your network is protected at all times. Both these methods have their advantages—making them the ideal choice depending on your network requirements and the type of assets you are trying to discover. Plus, Virima’s tool allows you to create a service map that shows where each asset is present and how it impacts the service delivery process within your organization. In turn, you know which asset is responsible for which services and how it contributes.If you are interested in investing in an automated IT discovery tool that continuously monitors your network, book a demo with Virima today.