Firewall Placement

I need help designing my network. Here is how its setup up now, but don’t think its right:

T1
|
Cisco Router
|(64.1.1.113/28)
|
switch
^ ^ ^
| | |(64.1.1.116/28)
| | Apache
| |
| |(64.1.1.115/28)
| W2K Exchange server
| |(10.0.0.2/24)
|(64.1.1.114/28) |
FreeBSD firewall |
|(10.0.0.1/24) |
| |
switch <----------- ^ ^ | | | Workstations(DHCP from W2K Exchange) | W2K File server(10.0.0.3/24) With these components what is the correct way to setup this network, the correct placement of each equipment. When you say "behind" the firewall, wouldn't that mean, in this senario, it would be on the 10.x network?? Please help, thanks in advance!! Thanks, Bill