--- title: "Hardware Air Gap: Comparison for IT Decision-Makers" date: 2026-04-02T10:25:00+02:00 author: FAST LTA canonical_url: "https://www.fast-lta.de//en/blog/hardware-air-gap-vergleich-für-it-entscheider" section: "Entries: Articles" --- ### Evaluation Criteria for Hardware Air Gap Solutions [\#](#evaluation-criteria-for-hardware-air-gap-solutions "Evaluation Criteria for Hardware Air Gap Solutions") #### 1. Manual vs. Automated [\#](#1-manual-vs-automated "1. Manual vs. Automated") **Manual approach (removable media, classically tape or USB):** The workflow depends on people: load the medium, run the backup, remove the medium, transport it to storage. The separation is real, but it has structural weaknesses: - Human error potential (medium forgotten in the drive, wrong medium loaded) - Slow recovery: the medium must be retrieved and read back sequentially - High administrative overhead, every cycle requires hands-on work - Coarse RPO: media rotation is typically daily or weekly, not hourly - A medium still sitting in the drive during an attack is online and destroyable **Automated, disk-based approach (Silent Brick Max Air, Silent Brick Pro):** - The backup process runs fully automatically - The hardware disconnects itself after each backup window: Silent Brick Max Air via galvanic separation, no physical removal needed; Silent Brick Pro via bricks that are physically removable from the Controller X - No manual media handling required for Max Air, and removal with Pro is a deliberate, simple operation - Data stays on disk: restores start in minutes, and integrity can be verified online - Higher initial investment, but far lower operational risk #### 2. RTO and RPO [\#](#2-rto-and-rpo "2. RTO and RPO") **RTO (Recovery Time Objective): how long can downtime last?** - Removable media in off-site storage: typically several hours to a full day; the medium must be retrieved, mounted, and read back - Silent Brick Max Air: typically well under two hours; the system reconnects and the data is immediately accessible on disk **RPO (Recovery Point Objective): how much data loss is acceptable?** - Manual media rotation: one day to one week, depending on discipline - Automated disk-based air gap: hourly to daily backup windows are realistic, because no human action is required Business logic: critical systems (directory services, ERP, databases) require small RPO and RTO, which only an automated air gap delivers. Manual media handling cannot keep up with those requirements. #### 3. Compliance Suitability [\#](#3-compliance-suitability "3. Compliance Suitability") Security agencies and auditors expect for backup copies: - **Offline state:** physically or electrically separated from the network - **Integrity:** demonstrably unaltered copies - **Audit trail:** access and backup operations logged - **Tested restorability:** documented recovery tests An automated disk-based air gap covers all four points and produces the documentation as a by-product of normal operation. Manual media handling can be made compliant, but the evidence depends on humans following the process every single cycle. Note: for statutory archiving (retention obligations), a separate hardware WORM archive such as Silent Cubes is the right tool; the air gap protects backups, the WORM archive protects records. #### 4. Integration into Existing Infrastructure [\#](#4-integration-into-existing-infrastructure "4. Integration into Existing Infrastructure") **Silent Brick System:** - Integration via standard protocols (SMB/NFS, S3, VTL for existing tape-oriented backup jobs) - Works with common backup software (Veeam, Commvault, and others) - Centralized management, no separate media logistics - Migration without a big bang: existing VTL-based jobs keep running on VTL volumes while new workloads write to parallel S3/NAS volumes on the same hardware **Legacy removable media:** - Works with existing backup tools, but requires separate hardware, separate processes, and ongoing media logistics - Recovery and verification remain manual #### 5. Costs [\#](#5-costs "5. Costs") Compare total cost over five years, not purchase price: - **Manual media approach:** lower hardware entry price, but recurring media purchases, storage logistics, and above all personnel time for every backup cycle. The hidden cost is operational: every manual step is a potential failure during the one week you cannot afford it. - **Automated disk-based air gap:** higher upfront investment in hardware plus maintenance, but minimal recurring labor and no media logistics. Over five years the totals typically converge; the difference is where the risk sits. With automation, the residual risk is hardware failure (addressed by redundancy). With manual handling, the residual risk is human error, which no budget line fixes. --- ### The Two Approaches in an Attack [\#](#the-two-approaches-in-an-attack "The Two Approaches in an Attack") #### Manual Removable Media [\#](#manual-removable-media "Manual Removable Media") Ransomware deletes the backup server. Older media in off-site storage are untouched, which is the point of the exercise. But recovery means retrieving media, mounting them, and restoring sequentially: hours to days. And any medium that was still connected at attack time is lost. #### Silent Brick Max Air (Automated) [\#](#silent-brick-max-air-automated "Silent Brick Max Air (Automated)") Backups run on schedule, for example nightly. After each backup the connection is galvanically severed. The device is offline and unreachable. When ransomware strikes, it finds no addressable backup target. For recovery, the system reconnects and the restore starts immediately from disk. The advantages: no human error source, fast RTO, isolation guaranteed by hardware rather than by process discipline. --- ### Evaluation Checklist [\#](#evaluation-checklist "Evaluation Checklist") #### Step 1: Define Requirements [\#](#step-1-define-requirements "Step 1: Define Requirements") - How large is the data volume (TB/PB)? - What recovery speed is needed (RTO in hours)? - How often do you need restores (daily, weekly, rarely)? - How long must data be retained (backups vs. archive obligations)? - Budget structure (CAPEX/OPEX)? #### Step 2: Evaluate Solutions [\#](#step-2-evaluate-solutions "Step 2: Evaluate Solutions") For each candidate: - Does the data volume fit the capacity? - Do RTO/RPO meet the requirements? - Is integration with existing backup tools possible? - Which compliance requirements does your auditor expect? - What are the total costs (CAPEX + OPEX + personnel) over five years? #### Step 3: Recovery Test [\#](#step-3-recovery-test "Step 3: Recovery Test") - Perform a complete restore test with time measurement - Test all critical systems (directory, ERP, database) - Simulate the ransomware scenario: air gap offline, then recovery #### Step 4: Documentation [\#](#step-4-documentation "Step 4: Documentation") - Document RTO/RPO and the backup schedule - Document the recovery procedure - Map each compliance requirement to the control that fulfills it --- ### Frequently Asked Questions [\#](#frequently-asked-questions "Frequently Asked Questions") **We still run a tape-based backup process. Do we have to replace everything at once?** No. The Silent Brick System provides VTL volumes that emulate tape for your existing backup jobs, so the software-side process stays intact while the media handling disappears. New workloads write to parallel S3 or NAS volumes on the same hardware. Note that VTL volumes and S3/NFS volumes are separate data paths for different data sets; they coexist on one system. **How often should we run a recovery test?** At least quarterly for critical systems. Every test should be a complete restore, not just a folder restore. **What if the air gap hardware fails?** Choose systems with built-in redundancy, and for higher requirements run multiple devices at different locations. Redundancy increases cost but removes the single point of failure. **Is a hardware air gap suitable for mid-sized organizations?** Yes. An automated, disk-based air gap with daily backups delivers secure backup and fast restore without dedicated staff for media handling, which is exactly what smaller IT teams need. --- ### Further Resources [\#](#further-resources "Further Resources") → Logical vs. Physical Air Gap: The Difference (/en/blog/logischer-vs-physischer-air-gap/) → Backup Media Compared Against Ransomware (/en/blog/backup-medien-ransomware-vergleich/) → Ransomware Recovery Checklist (/en/blog/ransomware-recovery-checkliste/) → Silent Brick System: Backup Storage with Hardware Air Gap (/en/produkte/silent-brick-system/) → Request a Demo (/​en/​kontakt/​demo/​) ### RTO / RPO RTO (Recovery Time Objective) is the maximum acceptable downtime after an IT failure; RPO (Recovery Point Objective) is the maximum acceptable data loss — both are metrics that must be technically demonstrably met in backup architectures and must not merely be defined as aspirational targets. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/rto-rpo) ### RTO / RPO RTO (Recovery Time Objective) is the maximum acceptable downtime after an IT failure; RPO (Recovery Point Objective) is the maximum acceptable data loss — both are metrics that must be technically demonstrably met in backup architectures and must not merely be defined as aspirational targets. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/rto-rpo) ### WORM WORM (Write Once, Read Many) refers to a storage principle in which data is written once and can technically no longer be altered or deleted — in hardware WORM, this immutability is a physical property of the storage controller, independent of software, operating system or user privileges. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/worm) ### WORM WORM (Write Once, Read Many) refers to a storage principle in which data is written once and can technically no longer be altered or deleted — in hardware WORM, this immutability is a physical property of the storage controller, independent of software, operating system or user privileges. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/worm) ### Ransomware Ransomware is malware that encrypts data on infected systems and demands a ransom for decryption — with the goal of forcing organizations and public bodies to pay by paralyzing their operations. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/ransomware) ### Air Gap An air gap is the complete physical interruption of all network connections between a backup system and the rest of the IT infrastructure, so that the system has no addressable network interface in its offline state and is therefore unreachable by ransomware and attackers. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/air-gap) ### Ransomware Ransomware is malware that encrypts data on infected systems and demands a ransom for decryption — with the goal of forcing organizations and public bodies to pay by paralyzing their operations. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/ransomware) ### Ransomware Ransomware is malware that encrypts data on infected systems and demands a ransom for decryption — with the goal of forcing organizations and public bodies to pay by paralyzing their operations. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/ransomware) ### Air Gap An air gap is the complete physical interruption of all network connections between a backup system and the rest of the IT infrastructure, so that the system has no addressable network interface in its offline state and is therefore unreachable by ransomware and attackers. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/air-gap) ### Air Gap An air gap is the complete physical interruption of all network connections between a backup system and the rest of the IT infrastructure, so that the system has no addressable network interface in its offline state and is therefore unreachable by ransomware and attackers. [Mehr erfahren →](https://www.fast-lta.de//en/glossary/air-gap)