Seeking Advice for Multi-Floor Wi-Fi Deployment in a 5-Story Building - Subnet/VLAN

[RLNG]

I have a situation where we have to install APs in a 5-floor bldg. Each floor is separated by an elevator so there is no expectation of seamless roaming when a user moves between floors as they get disconnected when using the elevator. Plus there are other offices on the remaining floors of the building.

So when designing should I put all APs (Around 100) in a single Subnet (/24) and all corp-users in a different single wifi-user VLAN (/22)? Or it's better if each floor AP should be on its own L3 subnet and the same for the clients. All VLANs are stretched across all floors. All Floors have the same number of APs and clients. 

Another question: How can we ensure that a user on Floor 2 doesn't connect to AP on Floor 3 .. etc.... This shouldn't happen but I am guessing it might. 

Can anyone offer some advice?

[alemabrahao]

I don't see the logic in creating an AP management VLAN for each floor.

The issue of clients is more complicated since the decision of which AP to connect is up to the device.

And I honestly don't think it's a viable thing to do, I don't see any benefit.

Unless you want to create different SSIDs for each floor, but I also don't think it's a good idea as it could end up polluting your wireless spectrum.

My recommendation is to keep it as simple as possible (of course with security in mind too) so you will have fewer problems.

[RLNG]

Thank you for your response. creating different SSIDs per floor is not an option. 

What about the reduction of broadcast/multicast domain by putting APs and Clients on different on different subnets per floor? Is this a benefit or not significant enough?  

[Ryan_Miles]

I agree with @alemabrahao and keep it simple. Put APs in a mgmt subnet. Drop clients in another subnet(s). A /22 isn't unreasonable for wireless networks. And with our APs you can use L3 firewall rules to stop some of the noise if you want (example, deny netbios and other unnecessary and chatty protocols). 

Not sure how many SSIDs you intend to have, but fewer is always the aim. As for the clients joining APs on other floors. There's nothing inherently wrong or bad about that. As @alemabrahao said roaming is a client decision and if a client can obtain a usable signal from another floor AP so be it.