I am worried that there is not really a benefit of doing that, just more noise and energy consumption.
Energy consumption is essentially the same, as it’s using the same radios.
For what it’s worth, I have several SSIDs, each on a separate VLAN:
- my main one
- Guest. Has internet access but is otherwise isolated - Guest devices can’t communicate with other guest devices or with any other VLANs.
- IoT Internet: IoT and home automation devices that need internet access. Things like Ecobee thermostat, Google speakers, etc
- IoT No Internet: Home automation stuff that does not need internet access. Security cameras, Zigbee PoE dongle (SLZB-06), garage door opener, ESPHome devices, etc
(to remotely access home automation stuff, I use Home Assistant via a Tailscale VPN)
Most of these have both 2.4Ghz and 5Ghz enabled, with band steering enabled to (hopefully) convince devices to use 5Ghz when possible.
This is on a TP-Link Omada setup with 2 x EAP670 ceiling-mounted access points. You can create up to 16 SSIDs I think.
That was an amazing read. Thank you.
What do you say is the use case for separating guest Wi-Fi with the more “private” stuff on your network?
As far as I understand… Basically all communications, even inside a network, are encrypted… So I guess you do that to avoid someone trying to exploit some vulnerability?
Basically all communications, even inside a network, are encrypted
LOL, oh no.
Even internet traffic isn’t encrypted by default.
Sadly TCP/IP isn’t encrypted.
Guest devices can’t communicate with other guest devices
How do you accomplish this isolation since they’re on the same subnet/broadcast domain? Is it a feature of the hardware you’re using?
A lot of access points, even consumer-grade ones, have this option. It’s usually accomplished via predefined firewall rules on the access points themselves.
Consumer-grade access points usually let you have just one isolated guest network, whereas fancier ones (Omada, Unifi, Ruckus, Aruba, etc) usually let you enable isolation for any SSID (ie the “guest network” is no different from any other SSID)
Isolated guest networks I get, but isolating guests from other guests on the same subnet/isolated net is what I haven’t seen.
Why would you want to do this, anyway? Or, as I as a developer regularly have to ask our sales people: what do you actually want to achieve that led you to this question?
Here’s my use-case, I’m pretty sure the first 2 are pretty common (common enough to be supported by most OEM firmware):
- main LAN
- guest LAN (isolated from “main” but can access internet)
- IoT LAN (isolated from internet, can be accessed from “main”; prevents devices from phoning home)
But you don’t need several LANs for this. This can easily done with proper routing. A can access internet and internal network addresses. B can only access internet, and C can only reach internal addresses.
I’m curious. How would you identify who’s guest and who’s not in this case?
With multiple networks it’s pretty easy as they are on a different network.
That’s what MAC whitelists are for. Your DHCP server should be able to handle this.
Identify your friendly devices and give them one setting with everything (full subnet and correct default GW). Identfy your IoT devices, and give them another (full, or specially limited subnet mask, and fake default GW, maybe a different nameserver, too). Anything else is guest and gets a very limited subnet mask and a working default GW.
This is not the way to do it. The correct way would be multiple SSID’s with each tagged to their own VLAN.
Each VLAN has its own subnet. You can then use a zone based firewall, to allow the zones(subnets) to access each other.
You can also then apply QOS, to limit guest network speeds, prioritize LAN traffic etc.
And zone based firewalls are stateful, you can do rules such as LAN can reach IOT, but not the other way. Or IOT can only reach the IOT server, on specific ports.
I am worried that there is not really a benefit of doing that, just more noise and energy consumption.
If there wasn’t a benefit, why would people (and pretty much every business) do it?
