VM NIC firewalls have been around for years (they’re also the reason I got my first invitation to the awesome Troopers conference), but it sounds so much better when you call them Microsegmentation (not the one I talked about @ Troopers this year).
Marketing gimmicks aside, VMware NSX includes an interesting in-kernel stateful firewall, and Brad Hedlund was kind enough to explain the intricacies of that feature in Episode 27 of Software Gone Wild
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