Elliptic curves to the rescue: tackling availability and attack potential in DNSSEC

Notes: Not quite ready for prime time, but moving to better security in the next year or so is on the roadmap. Something to consider if/when making a DNSSEC deployment.

Using elliptic curve cryptography, we can solve both problems with DNSSEC, because ECC offers much better cryptographic strength with far smaller keys and signatures. But using ECC will introduce one new problem: signature validation - the most commonly performed operation in DNSSEC - can be up to two orders of magnitude slower than with RSA. Thus, we run the risk of pushing workload to the edges of the network by introducing ECC in DNSSEC.

This talk discusses solid research results that show 1) the benefits of using ECC in terms of solving open issues in DNSSEC, and 2) that the potential new problem of CPU use for signature validation on resolvers is not prohibitive, to such an extent that even if DNSSEC becomes universally deployed, the signature validations a resolver would need to perform can easily be handled on a single modern CPU core. Based on these results, we call for an overhaul of DNSSEC where operators move away from using RSA to using elliptic curve-based signature schemes.