Re: [TLS] Breaking into TLS for enterprise "visibility" (don't do it)

Dan Brown <> Mon, 19 March 2018 15:18 UTC

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From: Dan Brown <>
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Thread-Topic: [TLS] Breaking into TLS for enterprise "visibility" (don't do it)
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Date: Mon, 19 Mar 2018 15:18:43 +0000
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Subject: Re: [TLS] Breaking into TLS for enterprise "visibility" (don't do it)
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Dear TLS WG,

Enterprise "visibility" is a network issue, not an Internet issue, and thus, to my _limited_ understanding, should be out of scope of IETF.

Nonetheless, enterprise security is important, and enterprise networks use Internet technology internally, so the topic is perhaps still procedurally discussable, so I continue.  I (naively) worry that "visibility" is also "siphonability", creating an incentive for a Snowden-sized (but malicious) leak, which could hurt enterprises and their customers.  In other words: who watches the watchers; avoid a single point of weakness; prevent social engineering opportunities; decentralize power; make sure the cure is not worse than the ailment; etc.  It is not yet clear (to me) which attackers "visibility" would thwart, but if it is just naïve (but plentiful) insiders, then I imagine the optimal solution would be better endpoint management (which may be a more difficult road than "visibility", but should still be the long-term solution).

Best regards,


PS: I never directly worked on enterprise security (usually, I just think about the math of basic crypto primitives), but I don't recall hearing about such a "visibility" feature in the enterprise security work of colleagues (whom I do _not_ speak for), e.g. one system used forward-secure ECMQV to establish a connection between smartphones and the enterprise network.