1. Why SLD Blocking Misses the Point Burt Kaliski, Verisign gTLD Collisions Workshop October 29, 2013

2. 2 Name Collision Problem for DNS Queries Installed System Global DNS without TLD ….SLD.TLD NXDOMAIN expected See Verisign Labs’ technical reports New gTLD Security and Stability Considerations and New gTLD Security, Stability, Resiliency Update: Exploratory Consumer Impact Analysis for further information.New gTLD Security and Stability ConsiderationsNew gTLD Security, Stability, Resiliency Update: Exploratory Consumer Impact Analysis

3. 3 Name Collision Problem for DNS Queries Installed System Global DNS with TLD ….SLD.TLD Resource record received (if SLD delegated) Internally Generated Query  collides with  Externally Assigned Name Potential Risks Installed System Breaks Internal Information Leaks (beyond root) Cyberattacks Exploit Collision

4. 4 Mitigating Name Collisions: General Approaches Installed System Global DNS with TLD ….SLD.TLD Resource record received (if SLD delegated) Internally Generated Query  collides with  Externally Assigned Name Potential Risks Installed System Breaks Internal Information Leaks (beyond root) Cyberattacks Exploit Collision (1) Remediate Installed System (3) Hybrid of Both (2) Constrain Global DNS

5. 5 How to Constrain the Global DNS? If we knew how all the installed systems used the global DNS … If we knew all the queries they might make … If we knew all the SLDs they might use...

6. 6 How Long Does It Take to Learn All the SLDs? A- and J-root data for 96-day period from July 16 to October 19, 2013. (Excludes non-LDH, “Chrome 10” strings.) Still growing after 90+ days …

7. 7 SLD ≠ Risk Query = Risk in context of installed system, application, protocol Qualitative Analysis minimize false negatives & positives solve problem Does It Even Matter?

8. 8 If SLD blocking for a gTLD leaves too much risk, how do we back out? Expedited approval process needs an expedited rollback process What If It’s Not Enough?

9. 9 New gTLD Security and Stability Considerations. Verisign Labs Technical Report #1130007. Version 2.2, March 28, 2013.New gTLD Security and Stability Considerations New gTLD Security, Stability, Resiliency Update: Exploratory Consumer Impact Analysis. Verisign Labs Technical Report #1130008. Version 1.1, August 27, 2013.New gTLD Security, Stability, Resiliency Update: Exploratory Consumer Impact Analysis Danny McPherson. Part 1 of 5; Introduction: New gTLD Security and Stability Considerations. Between the Dots, Verisign, May 9, 2013.Part 1 of 5; Introduction: New gTLD Security and Stability ConsiderationsBetween the Dots Danny McPherson. New gTLD SSR-2: Exploratory Consumer Impact Analysis. Between the Dots, Verisign, August 6, 2013.New gTLD SSR-2: Exploratory Consumer Impact AnalysisBetween the Dots Danny McPherson. New gTLD Queries at the Root & Heisenberg’s Uncertainty Principle. Between the Dots, Verisign, August 27, 2013.New gTLD Queries at the Root & Heisenberg’s Uncertainty PrincipleBetween the Dots Patrick S. Kane, Thomas C. Indelicarto and Danny McPherson. Re: ICANN’s Proposal to Mitigate Name Collision Risks –.CBA Case Study. September 15, 2013. Re: ICANN’s Proposal to Mitigate Name Collision Risks –.CBA Case Study Patrick S. Kane. Letter to Vernita D. Harris re: Joint Test Summary Report, RZM 2.0. May 30, 2013.Letter to Vernita D. Harris re: Joint Test Summary Report, RZM 2.0 For Further Reading Verisign Public

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