Opportunistic Wireless Encryption

1. Dan Harkins, Aruba Networks (an HP company) Opportunistic Wireless Encryption Authors: • Date: 2015-09-13

2. Dan Harkins, Aruba Networks (an HP company) Abstract • This submission presents an idea for addressing a problem with public wi-fi hotspots

3. Dan Harkins, Aruba Networks (an HP company) The Situation • Wireless Internet access as an entitlement– “oh, no wi-fi, let’s go somewhere else” • Coffee shop, bar, or restaurant wants to offer patrons “free wi-fi” • They want to provide a service but don’t want it to be a pain to configure or use • They want to provide some notion of both service and security to customers

4. Dan Harkins, Aruba Networks (an HP company) The Problem • Perpetual battle: Security vs Ease-of-Use • They want it to be easy-to-use • Don’t bug the staff too much– “no I said the L is capital” • Don’t irritate the customer– “wait, what? say that again” • Don’t require specialized knowledge– “what’s an EAP method? How do I configure an ‘anonymous identity’?” • They want some notion of security • Want it to be better-than-nothing security • Don’t want to have to get/generate/install a certificate • Secure access by patrons has to scale (see easy-to-use) • Result: Both sides lose

5. FAIL Dan Harkins, Aruba Networks (an HP company)

6. Dan Harkins, Aruba Networks (an HP company) The Solution? OWE • Make it simple to provision– just switch it on • Make it virtually impossible to misconfigure– no user entry required • Make public wi-fi “suck less” than it does when using a shared PSK • Raise the bar that is necessary to perform pervasive monitoring just a bit higher • OWE is an outgrowth of an IETF BOF on improving the captive portal experience

7. Dan Harkins, Aruba Networks (an HP company) IETF Proposal • https://tools.ietf.org/html/draft-wkumari-owe-00 • Network appears “open” to the user (no lock icon), uses a Vendor Specific Element in beacons and probe responses to indicate OWE • After association in an OWE network, STA and AP do the PSK authentication using the SSID as the password • Upside • No need to explain/enter anything, just works • Code changes AP side are trivial; STA side, manageable • Downside • Inherits all the security problems of shared PSK • Publicly advertises the PSK so arguably worse!

8. Dan Harkins, Aruba Networks (an HP company) My Proposal • Don’t do it in the IETF, let’s do it here • AP advertises an OWE AKM • When associating to an SSID with OWE include Diffie-Hellman exponentials in (Re)Associate Request and Resonse • STA and AP perform Diffie-Hellman, use shared secret to derive a PMK • Use this (truly pairwise) PMK with 4-way HS

9. Dan Harkins, Aruba Networks (an HP company) Benefits • More secure than a shared PSK • Not susceptible to passive attack • All those tools downloadable from Internet to crack PSKs won’t work! • Easier to set-up than PSK • Nothing to provision or describe, no user error • Easier to use by customers • Absolutely nothing needed to do! It just works. • Makes pervasive monitoring harder • Easier to use plus better security! Winner, winner!

10. Dan Harkins, Aruba Networks (an HP company) ขอขอบคณ ุ Thank You!

11. Dan Harkins, Aruba Networks (an HP company) Questions?

12. Dan Harkins, Aruba Networks (an HP company) OWE Straw Poll • Option 1: Good idea, we should do it! • Option 2: Bad idea, let the IETF do it! • Option 3: I was reading my email and not paying attention, sorry.