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Adding A Secondary Guest Network


Thinking of sub-letting your offices? Want to share your broadband connection with your tenants or give guest access to visitors?

How To

At its simplest, you'll need an additional router, but there is potentially a bit more to it than that if you want to prevent access by the tenant to your network completely.

One complication is if you connect the router up incorrectly - surprisingly common a mistake made by people un-aware of the consequences. If the tenants router has DHCP enabled (typically a factory default on most SOHO routers), under no circumstance should you allow that router to allocate DHCP addresses while on the main network – it will potentially knock out your whole network! Simply put, it shouldn't be connected into the main network at all while DHCP is enabled - and if you connect the router to the main network on the LAN side, that is exactly what you are doing.


For small networks, a simple cable modem type router (those with a network socket for the WAN side) could provide routing and NAT for the tenants secondary network. It will not necessarily prevent access to your devices though – this would need a redesign of your network too, or at the very least careful creation of firewall rules on one or other of the routers.

A more comprehensive solution can be achieved with a modern router that allows the creation of virtual 'guest' networks - please contact us for advice if you need it.

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