Fing for iOS
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Finally, you can disable the guest network without losing connection with other hardware. Why can you do this?
First, there may be a problem with your IoT or smart home technology. Keeping it separate from the main network is clearly a must. Disabling that hardware Internet connection while keeping other reliable technology online is also a wise thing. This can help you understand the problem.
Second, you can simply deactivate access to the guest network, when a visitor is no longer welcome or a child is watching children's programs on Prime Video beyond the allotted time.
Although parental control software is a better option for managing children 's access to the Internet, this is also very effective. Just remember to turn on the guest network again when needed.
For how to set up guest network, please refer to the article: How to set up guest network for Router for more details.