I did some digging and didn't find any decent docs on setting it up... but if you take your drawing from the L4TM question you posted, you want to set up a policy that for the "security vlan" so that all IP traffic on the web ports you want to monitor (80, 443, plus others you might want) gets sent to the IP of the WSAProxy
You'll want to have a look through Chapter 8 for the configuration. You've got to basically configure a traffic class, configure policies for it, and then apply it (in this case) to each of the VLANs you want it for.
What kind of firewall are you using? If its a Cisco ASA, it would actually be simpler to do WCCP to the WSA...
Table of ContentsIntroductionVersion HistoryPossible Future
UpdatesDocuments PurposeNAT Operation in ASA 8.3+ SectionsRule Types
Network Object NATTwice NAT / Manual NATRule Types used per SectionNAT
Types used with Twice NAT / Manual NAT and Network Obje...
Table of Contents Introduction:This document describes details on how
NAT-T works. Background: ESP encrypts all critical information,
encapsulating the entire inner TCP/UDP datagram within an ESP header.
ESP is an IP protocol in the same sense that TCP an...