Why WCF windows authentication?

Why use Windows auth开发者_开发问答entication for WCF service hosted on IIS, if I can limit accessing the IP range to be "localhost", Is there a security hole here.

if not, then why Windows authentication is supported by WCF, sense I can restrict IPs for all Intranet scenarios.

thanks

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If your IP range is stable (meaning very unfrequent changes on actual numbers) and you're comfortable with machines arbitrarly connected to your network having automatic access to your resources, then you may get away with your strategy. Most security officials though, will ask you to protect resources with user credentials, roles, and permissions.