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?
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.