Cisco ASA PAT Configuration

Hi Rene,

I dont know exactly what topic to place this question in thats why i am placing it here
i got an opportunity for 3 days to work under a CCIE who was very rude and did not bother to ask him any questions as i knew he was not interested in explaining

i was able to understand all bits till core SW through knowledge of your tutorials on VLAN and routing ,However cannot understand few bits in design at this point

They got a public IP block from ISP lets say 90.81.31.128/27 30 host count

Now the way the IP are assigned is as - 90.81.3.157 => ISP router LAN interface connecting to my ASA
- 90.81.3.158 => Outside interface of my ASA

Then there is CORE-SW- with different and server VLAN and few servers connected to server-vlan and require public access to them (web and email)[no-dmz].

For the purpose hiding internal IP-scheme NAT is configured at ASA pointing to server as follows

10.0.0.32 ===NAT===>90.81.3.132
10.0.0.42====NAT====?90.81.3.142
10.0.0.52====NAT====>90.81.3.152 …

So after all this lines my Question WHICH INTERFACE THIS IP 90.81.3.132 - 90.81.3.142 - 90.81.3.152 is assigned ,Where does this IP reside

-Do this IP remain in company network

please explain -As i know no one can expalain better than you in simple way

OH ! ATTACHED IS A DESIGN LAYOUT

Thanks in ADVANCE