Which approach is better - multiple SSIDs or single SSID

Question

I create a wireless network at the university, where we have a wide base of types of users, such as students (some of them have a course of study, some of PG, PhD students and others); support staff, faculties, resident staff (together with their families).

I need to design a wireless network, keeping in mind all these user bases.

I have two options for providing wireless access to users:

I need inputs (pros and cons) for these options -

OPTION I

A separate SSID for each category of users (for example, a separate SSID for IT students, a separate SSID for students in commerce, etc.).
If I go with this approach, I can create about 20 SSIDs, and in this approach I can apply policies based on the category of users and also limit the time period for different user groups.

OPTION II

The second option, I’m thinking of creating a single SSID for all users (or maybe 2/3 of the SSID). In this approach, I will not need to create an "n" SSID, and you will need to advertise ONE SSID for all users (and this will help me to simplify the simple).
But what I will miss in this approach is granularity and will not be able to apply different policies for different users.

I am open to any other approach, and I want to do my best. Please suggest with what approach I should go forward and, if possible, explain the pros and cons of the same.

Answer 1

The option with a large number of SSIDs is undesirable, since access points will transmit beacons for each SSID 10 times per second with the minimum required speed. It can consume significant airtime, especially if you need to support 802.11b / g standards. There are recommendations for using no more than 3-5 SSIDs on any single AP ( link1 , link2 ). Depending on the functionality of the network equipment, different policies may be applied for each client or for each user.

Answer 2

You can distinguish user groups using radius server and certificates. I believe that some APs may even use this to install specific VLANs. You get more flexibility, but you need to assign a certificate to each potential client.

or you can assign each user group to a different subnet thanks to the DHCP server (but this is not very secure, as people can manually change their IP address to get more privileges)