multiple SSID/VLAN config

[Jeremy Patrick]

If I could ask for a bit of education on the basics of configuring a corp/guest type of AP setup.  

Currently have a small business network with wireless being delivered via a 3502P and 1262 AP.  So far the network is using 10.10.4.x for addresses (dished out from a W2012R2 server), and up until now no need for VLAN segments.  I've worked with VLANs a bit in different environments so the switch config basics shouldn't be outside of reach.  (switches are HP)

The goal is to create a guest SSID and have guest traffic initially processed through a captive portal appliance.  

What I am a bit confused on is the actual AP configuration.  I've come across a few articles and posts about configuring the AP for an SSID and pairing it up with a VLAN but the confusion is on the process of routing the client guest's request for obtaining the correct scope address.

My base knowledge is this:

sample: Switch 2 has an IP of 10.10.5.50  Switch 1 has an IP of 10.10.4.50

Guest connecting via switch 2 requests an address, which the switch sends via the helper IP to 10.10.4.1 (DHCP server) The scope designed for 10.10.5.x dishes out an IP and it goes back to the requesting device.  

But... if an AP has the nic interface configured with an address of 10.10.4.20, how does the configuration go to have devices from different VLANs/SSIDs send a DHCP request via the helper IP and have it tagged to pull a non 10.10.4.x IP?  

Is the VLAN config on the AP set to a custom virtual address (i.e. 10.10.5.x) in order for the IP helper address to have a tagged address to relay to the DHCP server?

Thanks!

[kaaftab]

If I am not wrong your question is

 AP has IP 10.10.4.20 and its serving the IP address from 10.10.5.x

  wel its due to vlan and Mgt IP and its a normal practice usually followed to have different vlan for Mgt of devices. (e.g vlan 99 or somthing like that )

[Jeremy Patrick]

partially what I was aiming at.

I can see the overall aim is to have SSID 30 using VLAN 30 and SSID 40 using VLAN 40, but what I was getting hung up on was how does the traffic from each SSID get routed to the proper DHCP scope.  Yesterday I came across a few articles with sample configs listing a subconfig of the physical nic (i.e. gigabitethernet0.20 & 0.30) per VLAN, which if I'm correct in assuming is the way SSID traffic would be 'tagged' in a sense.

The main IP for AP config would still remain 10.10.4.20, but let's say for VLAN 30 would have a sub IP of 10.10.5.20 and VLAN 40 would have a sub IP of 10.10.6.20

Am I heading in the right direction for understanding this?