Per VMWare, You can disable the Windows PC networking for security. Read the notes below:
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http://www.vmware.com/support/fusion/doc/releasenotes_fusion.html
Before You Begin
Install antivirus software in Windows virtual machines before you connect networking.
Connecting a Windows virtual machine to a network exposes the virtual machine to any active viruses present in the network. VMware recommends that you install antivirus software in any Windows virtual machine before you connect networking. Note that VMware Fusion's default network connection type for new virtual machines is NAT, which will prevent the spread of viruses over the network into the virtual machine, and will only expose the virtual machine to external viruses through browser security flaws when you browse the Internet.
