What is an Air Gap? Benefits and Best Practices

The phrase “air gap” happens to be cited frequently inside the cybersecurity domain as one of the basic but effective techniques for making a system or data safe. In this respect, understanding what an air gap is and reviewing its benefits and best practices can become crucial for an organization. The blog in a very detailed manner will discuss what an air gap is, its importance, and the way it operates, the benefits and limitations of the technique in the broader landscape of cybersecurity.

What is an Air Gap in Cybersecurity?

The air gap is a security measure that requires the computer or the network to be isolated from other systems, more particularly from the Internet or any external networks. This isolation is achieved by ensuring that certain so-called “air-gapped” systems are without connections, physical or electronic, to the outside world. By definition, an air-gapped system would mean one that’s totally “air-gapped” from the rest of the outside world; hence, by design, it should be impervious to remote hacking attempts.

Is the Air Gap Dead?

Air gaps were considered an unassailable alternative to securing critical systems; however, with the advancement of cyber threats and sophisticated attack vectors, this perception is now slowly being tainted. Quite to the contrary, air gaps, because of challenges to their purported invulnerability by modern advanced persistent threats, are argued conversely to continue forming a useful component of the cybersecurity toolkit, particularly when used in combination with other security controls.

Importance of Air Gapping

With sensitive data and other systems, air gapping becomes essential for the systems that hold these very sensitive information and even control very large critical infrastructures. In such a situation, organizations can protect against a wide range of cyber threats by physically or electronically isolating these systems.

1. Remote Attacks: In this setup, air-gapped systems are fully isolated from the internet and network connections; therefore, it is impossible for any remote system to go ahead and hack or attack it if it is dependent on network connectivity. There are no entry points into which hackers can exploit vulnerabilities to gain unauthorized access or disrupt operations.
2. Malware: Isolated from network connections, air-gapped systems are not as susceptible to malware infections that come through network traffic or other online sources. Even if malware is somehow introduced physically, the damage caused by it is contained and it cannot spread to the other systems.
3. Data Exfiltration: In its design from the ground up, air-gapping ensures that no transfers or copies of data can be made that are unauthorized, thereby preventing the transfer of data outside of an environment. It makes the job much tougher for an infiltrator to siphon information or malware to externalize information from the environment, thus protecting vital information from unauthorized access or leaks.

Types of Air Gaps in Cybersecurity

There are several types of air gaps, each serving different purposes based on the level of isolation required:

1. Physical Air Gap – There is a purely physical separation between the systems; there can be no direct or indirect electronic interconnection. This refers to the idea that an air-gapped system is entirely cut off for real from the internet and other networks. Any type of remote access or data transfer by electronic media is impossible. This provides maximum security as every kind of potential pathway in the electronic version can be eliminated, hence making the infrastructure controls suitable for highly sensitive systems.
2. Logical Air Gap – In a Logical Air Gap, separation is provided through the configuration of the network as opposed to actual physical disconnection. It is implemented using network technologies and technologies like VLANs and Firewalls to restrict and segment network traffic. While the system is physically connected, the system interactions indeed are limited and regulated primarily by the network rules. So, in that case, it offers a flexible way to isolate sensitive systems in a network; thus, requiring no physical separation.
3. Hybrid Air Gap –  A Hybrid Air Gap is a mixed version using both physical and logical isolation to enhance security. It will separate the systems physically, accompanied by network configuration controls to build multiple layers of protection. In this way, with one layer of security broken, there is always another layer to continue providing security, making this approach very useful in scenarios where isolation at both the physical and network levels is necessary for the best protection.

How Does the Air Gap Work?

The air gap works by severing any possible pathways through which external threats could interact with the isolated system. This can be achieved through:

1. Disconnecting Network Interfaces – One of the basic ways to implement an air gap is through the physical disconnection of network interfaces. A network interface could be unplugged with network cables, disabling Wi-Fi, or switching off any other kind of wireless communication. This makes the air-gapped system completely disconnected from all the other external networks and the vast internet. The system disconnection ensures that there is a blockade on any data flow between the isolated system and any external source. This then blocks attempts at a remote cyber attack against the system and unauthorized access attempts. Therefore, the system is immune from network-based threats or other forms of intrusion.
2. Restricting Physical Access – Another very major issue that deals with the proper maintenance of an effective air gap is the control of physical access to the isolated system. This implies that only the designated people are allowed physical entry into the air-gapped milieu. Therefore, access controls may range from a mere lock on a door to even complex surveillance devices, all in an effort to avoid the actions of unauthorized persons who may seek to interfere with the system. In this regard, organizations reduce the chances of an insider threat, an accidental exposure, or a physical attack that might trigger the loss of the air-gapped system’s integrity.
3. Implementing Strict Data Transfer Controls – The air-gapped system has no option but to use controlled and secured data transfer means because it is cut off from an external network. For instance, the USB drives or some other removable media through which the data is transferred are first scanned for malware before making contact with the system that is air-gapped. This ensures no volume is infected and does not, in any way, introduce malware into the system. Additionally, data transfer procedures are often governed by strict protocols to further reduce the risk of introducing vulnerabilities or unauthorized data access.

Air Gap Network Implementation (Setup)

Setting up an air gap involves several steps to ensure effective isolation:

1. Design the Architecture

This involves the design of the system’s architecture as the first step in setting up an air gap. This is like realizing some particular systems that require isolation and making physical and logical plans for them. You have to determine which systems handle sensitive or critical data, and then, decide how best to physically separate such systems from other networks. This may lead to dedicated rooms or facilities, which may need changes in network configurations to be fully isolated from other systems.

2. Isolate Networks

Ensure that there are physical network isolations. This means that all network interfaces must be disconnected from the air-gapped system. This includes the unplugging of network cables, the disabling of wireless connections, and any other electronic communication modes that may apply. The use of physical security barriers, such as locked rooms or secure areas may be put to isolation. It is necessary to make sure that no indirect connectivity may be used to bridge the air-gapped system to external networks.

3. Control Data Transfer

Manage data in and out of the air-gapped system with utmost care using malware-scanned USB drives or other removable media. First of all, any data entering the air-gapped system should be checked for security threats. The transfer of data should be limited to authorized personnel to be controlled and for safety purposes, and strict procedures for the processing and documenting of these should be put in place.

4. Monitor and Audit

Finally, develop monitoring and auditing procedures that ensure the efficiency of the air gap. There should be monitoring tools that observe all activities happening on the isolated network and any other cases of unauthorized access or other events that are out of the ordinary. There should be regular audits to inspect the proper functioning of the air gap, assess physical controls over access, and verify the integrity of the network isolation. Keep on refining and developing security measures in light of audit findings and new threats to ensure strong protection.

Air Gapping Benefits

1. Air gapping is a security measure that involves the isolation of a computer or network from any external connection, such as the Internet or other networks. Isolation comes with a bunch of key advantages that make it an essential strategy in environments where security levels need to be very high.
2. Security is one of the most important reasons for air gapping. Air-gapped systems are usually much less vulnerable to remote attacks because of the removal of any type of external connectivity that might include hacking, ransomware, and many other forms of malware needing network access to propagate or be detonated. In other words, these systems are not vulnerable to common threats affecting connected networks; hence, they turn out to be more secure.
3. Another critical advantage is protection against data exfiltration. In a connected world, unauthorized data transfers or leaks are quite doable through many channels, including the internet or removable media. Air-gapped systems reduce that risk. The risk is significantly reduced because the physical prevention of external access makes it way more complicated for unauthorized parties to extract sensitive information.

Air Gapping Limitations and Challenges

Air gapping offers strong security but also comes with challenges:

1. Operational Complexity

For a line of air-gapped systems, the operations associated with manually transferring data and changes are very complex within an operating environment.

2. Limited Flexibility

Isolation restricts data transfer and integration with other system sets that could have boosted efficiency and encouraged collaboration.

3. Insider Threats

Insiders who can access the system even if directly linked to any external location can introduce malware or jeopardize data.

These limitations highlight the need for careful planning and stringent internal controls to complement the security benefits of air gapping.

Air Gapping Best Practices

To maximize the effectiveness of an air gap, consider the following best practices:

1. Regularly Update and Patch Systems

A strict regimen of updating and patching systems will help to maintain security in air-gapped systems. It can still be a manual process that involves the transfer of patches using media devices, such as USBs or other external drives, from a secure system to one with an air gap.

It comes as a result of the manual process that any updates have to be downloaded from the original sites that are trusted and then scanned for any malware before transferral to them.

2. Use Controlled Data Transfer Methods

Every data transfer to and from the air-gapped system has to be carefully managed to avoid any security compromise. All removable media for it is also designed to be scanned for any malware before linking it to the isolated system.

That is a protective measure to ensure that under no circumstance during data transfer is malicious software introduced into sensitive computer systems. In such a case, applying data being transferred, or encryption imposes an extra layer of safeguarding, preventing access to such data even if this is compromised from a gypped or snoop by unauthorized elements.

3. Implement Strong Access Controls

Taking into account that systems with an air gap cannot be fully isolated from any form of connection to other equipment, access to its systems should be restricted. There should probably be physical as well as logical control.

This should generally take the scope of the access controls to the actual location of the air-gapped systems—probably access points and inclusive monitoring through secure entrances. Logically, the systems themselves should be well-protected using strong authentication that may include multi-factor authentication, to ensure just the right people have access.

4. Regularly Monitor and Audit the System

Continuous monitoring and auditing are essential for maintaining the security of air-gapped systems. Monitoring tools need to be in place for purposes of keeping track of as well as logs on the activities of the systems.

This enables the detection of the most unusual behavior and potential breaches in security in real time. The isolated environment of air-gapped systems calls for monitoring and auditing to be done from within the isolated environments.

Use Cases for Air Gaps

Air gaps are particularly effective in the following scenarios:

1. Critical Infrastructure

Protection for systems that control critical infrastructure, such as the power grid or industrial control systems.

2. Sensitive Data Handling

The process of protecting systems processing or storing extremely sensitive information, such as government or financial data.

3. Research and Development

Protection of intellectual property and proprietary research from any form of external threat.

Air Gap vs Other Security Measures

To understand where air gaps fit within the broader security landscape, let’s compare them with other measures:

1. Comparison with Firewalls

1. Air Gaps: Provide complete physical and electronic isolation, blocking all remote attacks since there is no network connectivity.
2. Firewalls: Control network traffic based on rules and can block unauthorized access, but can be breached if misconfigured or if there are vulnerabilities.

2. Comparison with Network Segmentation

1. Air Gaps: Ensure total separation between systems, preventing any communication with external networks.
2. Network Segmentation: Divides a network into isolated segments to reduce risk, but does not offer absolute isolation and can still be accessed remotely.

3. Comparison with Intrusion Detection Systems (IDS)

1. Air Gaps: Prevent external threats from reaching the system by providing total isolation, thus avoiding initial breaches.
2. IDS: Detect and alert on suspicious activities within a network but do not prevent initial breaches or unauthorized access.

In summary, air gaps offer the highest level of isolation, while firewalls, network segmentation, and IDS each provide different types of protection with specific limitations.

Myths and Misconceptions about Air Gap

Several myths surround the concept of air gaps. Let’s decode a few of them:

Myth: Air Gaps Are Completely Infallible

Explanation: Despite air gapping being the most secure type of security control because systems are physically separated from outside networks, it is not wholly resistant to all types of attacks. The effect of an air gap project facilitates the entry of remote and network-based threats, however, other risks are not totally eradicated by air gaps. Examples include:

• Insider Threats: Since the air-gapped system provides physical access to individuals that have access, it’s possible to exploit such access to inject malware, steal data, and cause damage. Literally, this is a great risk because insiders are not constrained by the air gap.
• Sophisticated Physical Breaches: In such a scenario, greater-level attackers may attempt a physical breach of security for the air-gapped environment, which might include techniques like malware through physical device implantation or exploits on physical security measures.
• Social Engineering:  Social engineering is another way through which attackers may try to outwit or deceive authorized personnel to gain entry into the system or solicit compromising information.

Myth: Air Gaps Eliminate All Risks

Explanation: While air gaps enormously reduce the threat of remote attacks or any other forms of attacks that are entirely network-based, they by no means reduce every form of security risk. This could involve certain risks, including:

• Insider Threats: Even in the absence of an external connection, the insiders who have access to the air-gapped system turn against it, either by inserting malicious code or by misusing the provided access.
• Physical Tampering: This could include attacks that result in actual physical tampering with the system or component, either by inserting compromised hardware or distorting the environment in ways that exploit vulnerabilities.
• Inadequate Data Transfer Practices: The data transfer cycle between an air-gapped system and external networks, say, by use of USB drives, can turn into a potential risk if not managed properly. This may include lousy practices while scanning the media, insecure procedures, or some other modes of transfer likely to accidentally introduce malware or result in a data breach.

Real-World Examples of Air Gaps

Real-world examples of air-gapped systems include:

1. Critical Infrastructure Control Systems: Many industrial control systems and SCADA systems use air gaps to protect against cyber threats.
2. Government and Military Networks: High-security environments often employ air gaps to safeguard sensitive data and operations.
3. Military Networks: Military networks are often air-gapped to prevent unauthorized access and protect sensitive information from falling into unwanted hands. For example, in the US, the classified networks of the Department of Defense are air-gapped to avoid hacking and data breaches of email systems.
4. Financial Companies: Air-gapped networks can be implemented in financial institutions, mainly at sites for sensitive transactions or at locations hosting large amounts of data related to customers, so hostile forces cannot hack into them and result in data breaches.
5. Healthcare Organizations: Those healthcare organizations dealing with sensitive information, such as handling patients’ data or studying infectious diseases, may have air-gapped networks to protect them from unauthorized access and guard against data breaches.

How SentinelOne Helps Organizations with Air Gaps?

SentinelOne offers danger cover that improves air-gapping strategies with complementary cutting-edge endpoint security solutions for organizations. It continuously monitors air-gapped environments for potential threats.

The platform enables automated responses to detect threats and reduce various security risks. It enhances visibility to endpoint actions to identify anomalies and potential exposures. Organizations can conduct remote security monitoring of their networks and isolate or make devices invisible within them.

By enforcing the principle of least privilege access and zero trust security, SentinelOne protects all deployments across public, private, and hybrid clouds, and secures air-gapped networks. The SentinelOne Management Console centralizes insights and if you need a personal cyber security analyst, then Purple AI will be your new best friend. Generate actionable threat intelligence by ingesting raw data from multiple and diverse data sources by using Singularity Data Lake. Create automated backups, protect your organization, and prepare for future incidents with advanced threat detection and incident management capabilities.

It uses an agentless deployment to detect and respond to threats over the air-gapped network, which does not mandate the installation of agents or software. Besides, security teams can proactively hunt for threats on air-gapped networks using SentinelOne’s advanced threat-hunting capabilities to identify and respond to potential threats before they transform into major events.

Conclusion

In summary, air gaps remain indelible security measures for the protection of sensitive systems and data. They have their drawbacks and challenges but are significantly good at providing isolation against external threats. By better understanding these benefits, limitations, and best practices, organizations can gain the upper hand in protecting critical assets in their care against the continuously evolving threat landscape.

FAQs

1. What is an air gap in cybersecurity?

An air gap is a security measure that involves physically or electronically isolating a computer or network from other systems, particularly external networks, to prevent unauthorized access and attacks.

2. Can air-gapped systems still be vulnerable to attacks?

An air-gapped system can still experience compromise from various vectors, such as insider threats, as well as physical and increasingly sophisticated attack techniques that target the physical or human layer.

3. What is the purpose of an air gap?

An air gap serves isolation and, therefore better security by not having any electronic or physical form of connection between the vital system and the outside networks; hence, reducing the risk of remote attacks and unauthorized data transfer.

4. How does air gapping enhance cybersecurity?

The security of these systems is improved by air gapping because it isolates critical infrastructure from outside networks, thus reducing the attack surface and mitigating the risk of remote threats and malware attacks.