As it's title suggests, this article deals with the security issues related to virtualized edge deployments. Hopefully, this will provide an alternative solution for those who are also interested in the next subject:
This article is targeted at those ISA deployments where the combination of ISA and a domain controller are intended to operate on the same OS instance. While this combination is far from a best practice, the undeniable fact is that many customers choose to do this and so we've provided a reference for those same customers and the support engineers they inevitably call.
Jim Harrison, Program Manager, Forefront Edge SE