In our Bad-Fi segment of episode 102 of the Wireless LAN Professionals Podcast, Eddie Forero shared why placing APs in the hallway is a bad idea (at least in his view).
What’s the deal with APs in the hallways?
How many times have you been in the hotel with Bad-Fi? More than likely, you’ll notice that all the APs are lined up in the hallway. Unfortunately, this is quite common.
The biggest problem with APs in the hallway is that radio frequency (RF), like water, travels the path of less resistance. So an AP in the hallway will always be “loud and clear” along the hallway but not so much in the rooms themselves. Maybe the room that AP is directly outside of – but that’s about it.
The bane of hospitality!
Are hotel guests congregating in the hallway to watch Netflix? I doubt it! So if and when it is possible, place APs within the rooms where the users of the Wi-Fi actually are.
To the hotel, it makes practical and economic sense to place APs in the hallways. It also seems logical that it will spread among all the rooms and thus you will need less APs.
The truth is quite the opposite.
What is really created is a situation where all the APs are loud and clear and can easily hear each other. So there is really no way for you to get channel re-usage especially at 2.4 GHz and RF is probably just sloshing up and down the hallway because it is easier to travel down the hallway than to propagate through walls and bathrooms.
The Solution – Place the APs where your clients are!
So, it’s not to say that placing APs in the hallways is not a doable or a valid option. Sometimes you have no choice. But you have to understand what your limitations are and how to best work within those limitations.
This could be using directional antennas, crisscrossing in the hallways to keep co-channel interference down, and pointing your RF to where your clients are, helping that RF push through the walls instead of going along the hallways.
Another option would be to place APs in the rooms and using the building infrastructure itself to provide separation between cells.
This way you are indeed placing the RF where the users are and can get the most channel reuse possible. The downside to this solution is that it may require more APs that the hallway solution, however this would bring about a better user experience.
The following is a link to a video that can help you understand how RF signals propagate when APs are placed the in the hallway vs how it propagates when place in rooms. https://badfi.com/blog/aps-in-hallways-dont-do-it-from-eddie