A smart home is supposed to make life easier: lights by voice, heating from your armchair, the camera at the front door on your phone. But every connected device brings two questions many people underestimate: who can access it, and which data leaves your four walls? Both are very manageable if you take a structured approach from the start. In Germany, 48 percent (Bitkom) of people now use at least one smart-home application, and 87 percent (Bitkom) of users deliberately pay attention to data security and privacy when buying. That is exactly where this guide comes in. We show step by step how to sensibly separate your home network, secure updates and accounts, and stay data-frugal – and why a calm setup at your home makes the difference between theory and lived security.
Key takeaways
- Security and privacy in a smart home are not a matter of luck but the result of a few clearly ordered steps.
- A separated home network (a guest or IoT network for smart devices) is the single most effective building block.
- Automatic updates and strong, unique accounts with two-factor protection close the most common entry points.
- Data frugality means: prefer local processing, use the microphone and camera deliberately, grant only the permissions that are needed.
- From 2026 the Cyber Resilience Act introduces an update obligation for new devices – it is worth checking the update promise when buying.
- Setup at your home ensures the protective measures are actually active and remain easy to use day to day.
Why security and privacy belong together
Many people think of smart-home risks first as hacker attacks, others mainly as a privacy issue. In truth, the two are closely linked. A poorly secured device is not only an entry point for outsiders; it often sends out more data than necessary. Conversely, a data-frugal setup still protects a great deal if something does go wrong, simply because less sensitive information is in transit. Security and privacy are two sides of the same coin.
The figures show clearly that this topic moves people. Among those who deliberately avoid smart home, 48 percent (Bitkom) cite the fear of data misuse and 41 percent (Bitkom) the fear of hacker attacks as the reason. Among users, in turn, 96 percent (Bitkom) would like an independent seal confirming a high level of protection against attacks. The need for security is not a niche concern but a majority view – and it can be met with manageable effort.
A realistic attitude is important here. No connected system is immune to every conceivable attack, and serious advice does not promise that either. The point is a clearly higher level of protection with reasonable effort: closing the obvious entry points, reducing data and keeping an overview. Anyone who follows these basics makes life noticeably harder for attackers and keeps control over their own information. You can read more about how devices work together in our article on the Matter standard 2026.
Smaller attack surface
A separated network, up-to-date software and strong accounts close the routes attackers use most often.
Less data outflow
Local processing and deliberately set permissions keep as little as possible leaving your home.
More oversight
Knowing which device may do what and where it sends data means staying in control instead of trusting blindly.
Splitting the home network correctly
The single most effective step for a secure smart home is separating the home network. The idea is simple: your personal devices such as computer, smartphone and tablet belong in a main network. Smart devices such as lamps, sockets, robot vacuums or the camera doorbell belong in their own, separate network. Many modern routers offer a guest network that is well suited to exactly this purpose. That way, an insecure smart device that does get compromised cannot readily access your private files, photos or online-banking devices.
The German Federal Office for Information Security recommends precisely this network segmentation as one of the central measures for the connected home (BSI). Smart devices are often in use for longer, receive updates less frequently and are therefore more vulnerable than a regularly maintained smartphone. By isolating them from the main network, you limit the potential damage from the outset. It is comparable to fire doors in a building: they do not prevent every fire, but they keep it from engulfing the whole house.
In practice this does not require an expensive special device. Often it is enough to activate the router's existing guest network, name it sensibly and consistently register all smart devices there. During the initial setup it pays to do this right away rather than laboriously moving every device later. That is exactly what we handle during the WLAN setup at your home together with you – including a clear explanation of which device sits in which network and why.
Tip: the guest network is your IoT network
Updates: the invisible shield
Software is not finished. Manufacturers use updates to close security gaps that become known after the sale. A device that no longer receives updates, or where they are not installed, gradually becomes an open door. The BSI explicitly points out that IoT devices without updates pose a considerable security risk (BSI). The invisible but decisive shield of a smart home is therefore how current its software is.
The most convenient route is to enable automatic updates wherever the device and its app offer them. Then you do not have to remember yourself, and gaps are closed promptly. Where there is no automation, a fixed routine helps, such as an update check once a month. It is also important to check the update promise when buying new devices: how long does the manufacturer promise security updates? Devices with no clear statement are a risk that can be avoided.
From 2026 there is additional support from legislation. The European Cyber Resilience Act introduces binding cybersecurity requirements for connected products; from December 2027 products with digital elements may no longer be sold in the EU without conformity at all (BSI). Devices are then to be supplied with security updates over an appropriate period, and at least five years is frequently discussed (heise). For consumers this means: new devices will tend to stay secure for longer. Until then, and afterwards, the rule remains: updates have to be installed, otherwise the best promise is worthless.
| Area | Recommended | Avoid |
|---|---|---|
| Update behaviour | Automatic updates on or a fixed monthly routine | Updates not installed, app not opened for years |
| Buying a device | Manufacturer with a clear update promise (often 5 years from 2026) | Cheap device with no stated update period |
| Old devices | Retired once updates stop | Still online although support has ended |
| Router | Firmware current, auto-update on | Years-old firmware, default password |
Securing accounts and passwords
Smart devices usually hang on an online account: the manufacturer's account, an app or a voice assistant. This account is often the real master key. Whoever takes it over may be able to view cameras, control doors or extract data. Securing accounts therefore deserves at least as much attention as the devices themselves. A reused password that has already been stolen elsewhere is one of the most common causes of hijacked accounts.
Three rules carry most of the security here. First: a separate, long password for every important account. A password manager helps so you do not have to remember everything. Second: switch on two-factor authentication wherever it exists. Then a stolen password alone is no longer enough, because a second proof is also required. Third: change default passwords immediately. The BSI stresses that devices shipped with default credentials are a frequently used entry point (BSI).
A frequently used entry point for attackers are devices that are only protected by preset default passwords.
The router in particular deserves a close look, because it is the control centre of the entire home network. Default credentials for the router interface should be changed, unneeded services such as automatic outward device exposure should be switched off, and the WLAN encryption should be brought up to date. That sounds technical, and in the detail it is – which is why we set up exactly these points during a home visit together and leave you a clear overview.
- Use a separate, long password for every important smart-home account.
- Activate two-factor authentication everywhere it is offered.
- Change the default passwords of the router and devices right during setup.
- Delete accounts you no longer use instead of leaving them open.
- For shared family access, use separate profiles rather than one shared login.
Setting up data-frugally
Data frugality is a core idea of data protection: only the data that is genuinely needed for the purpose should be collected and processed. The General Data Protection Regulation requires exactly this, and many smart-home devices collect more than they need to in their default settings (Verbraucherzentrale). The good news: a lot can be deliberately reduced during setup without giving up comfort.
The first lever is the choice between cloud and local processing. Not every smart solution has to send its data to the cloud. Local systems can connect a home without information leaving the house (Verbraucherzentrale). Where a local option is available and practical for everyday use, it is usually the better choice from a privacy point of view. Where the cloud is needed, it is worth checking the settings: history data, voice recordings or usage analytics can often be limited or deleted regularly.
The second lever is the microphone and camera. Both are useful, but they are also the most sensitive sensors in the house. The Verbraucherzentrale advises switching off the microphone for confidential conversations via the physical mute button and preferring cameras with a physical cover (Verbraucherzentrale). A camera whose lens is mechanically covered cannot record anything – regardless of software and settings. Such deliberate decisions give back a good sense of control.
Local before cloud
Where local processing is possible and practical, keep it preferred – so less data leaves the house.
Microphone on purpose
Use the physical mute for confidential conversations and delete voice recordings regularly.
Cover the camera
Prefer models with a physical cover and place cameras only where they are truly needed.
Check permissions
Give apps only the access they need – do not grant location, contacts or microphone across the board.
Delete data
Clean up history and usage data regularly instead of letting it grow without limit.
Separate accounts
Keep smart-home accounts separate from central accounts such as email so one incident does not affect everything.
Data-frugal does not mean inconvenient
How we approach the setup
Knowledge alone does not protect. What matters is that the measures are actually active and work in everyday life. That is exactly the advantage of a setup at your home: we implement the points together with you, check that everything takes effect, and explain clearly what is happening. Nobody is left alone with cryptic menus. This applies to young families just as much as to older people, for whom we take particular time – more on this in our article Smart home for seniors.
Our approach follows a fixed order so nothing is forgotten. We start with an inventory: which devices are present, what should the smart home achieve, what concerns are there? Then we separate the home network, bring the router and devices up to date, secure the accounts and go through the privacy settings. Finally there is the briefing: afterwards you should be able to operate the system securely yourself.
Because we come to you by car in the Hildesheim and Leine valley region, much of it can be done in a single appointment. If a WLAN problem is in the way, we sort that out at the same time – a stable, well-covered wireless network is the basis for any reliable smart home, as we describe in detail in our article whole-home WLAN with mesh. And if questions come up later, we are reachable without you having to fight your way through a call centre.
Security you do not notice day to day
Sources and studies