Creating a Wi-Fi network called “Guest” makes it easy to tell visitors where to connect. The name alone, however, does not establish what those visitors can reach.
The useful configuration question is whether guest devices can access the main local network, communicate with one another, or only use the internet. Those permissions depend on the router, operating mode, and selected options.
Define the access you intend to provide
For a visitor who only needs web access, the requirement may be simple: reach the internet without accessing office computers or shared storage.
A meeting room may have a different requirement if guests need to use a presentation device. That exception should be deliberate rather than discovered after enabling broad local access.
Write the requirement before changing settings. “Visitors can browse the web and cannot reach the NAS” is more testable than “make the Wi-Fi secure.”
Keep the administrator interface and credentials separate from the information supplied to guests.
Inspect local-access and guest-to-guest settings
TP-Link’s router documentation distinguishes an option allowing guests to communicate with each other from an option allowing access to devices on the main network or LAN ports. These are separate permissions.
That distinction is useful even when another manufacturer uses different labels.
A guest device being unable to find another guest does not prove that it cannot reach the main network. Similarly, working internet access does not prove that local access is restricted.
Inspect the exact model’s manual and interface. Avoid applying a screenshot from a different router as though it establishes your device’s behavior.
Check the router’s operating mode
The same hardware family can behave differently depending on whether it operates as a router or access point.
TP-Link’s Deco documentation, for example, describes guest/main-network isolation in Router mode and an “Allow Local Access” control for the documented Access Point configuration.
This makes operating mode part of the configuration record. If the network is later reorganized, revisit the guest settings rather than assuming the old arrangement remains intact.
Also note which device actually provides routing. In a home or small office, several boxes may broadcast wireless networks while only one performs that role.
A simple list of equipment and modes is often enough to prevent confusion.
Test from a guest device
Connect a device to the guest network and verify internet access. Then test the specific local services that should be unavailable, using only equipment you own or administer.
Do not rely exclusively on a failed ping. A device can ignore ping while another service remains reachable. Test the relevant access requirement directly.
If guest-to-guest communication is also restricted, test that separately with two authorized devices.
Record the result and retain a short configuration note. Recheck after replacing the router, changing operating mode, or making significant network changes.
A guest network is useful when its permissions match the intended visit. The network name helps people connect; the configuration and testing establish what that connection allows.
Sources: TP-Link: Create a guest network on Wi-Fi routers · TP-Link: Set up a guest network on Deco