12 September 2012
Certificate Transparency IETF Working Group 2
Network Working Group B. Laurie
Internet-Draft A. Langley
Expires: March 16, 2013 E. Kasper
September 12, 2012
The aim of Certificate Transparency is to have every public end-
entity TLS certificate issued by a known Certificate Authority
recorded in one or more certificate logs. In order to detect mis-
issuance of certificates, all logs are publicly auditable. In
particular, domain owners will be able to monitor logs for
certificates issued on their own domain.
In order to protect clients from unlogged mis-issued certificates,
logs sign all recorded certificates, and clients can choose not to
trust certificates that are not accompanied by an appropriate log
signature. For privacy and performance reasons log signatures are
embedded in the TLS handshake via the TLS authorization extension
[RFC5878], or in the certificate itself via an X.509v3 certificate
In order to ensure a globally consistent view of the log, logs also
provide a global signature over the entire log. Any inconsistency of
logs can be detected through cross-checks on the global signature.
Logs are only expected to certify that they have seen a certificate
and thus, we do not specify any revocation mechanism for log
signatures in this document. Logs will be append-only, and log
signatures will be valid indefinitely.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
Laurie, et al. Expires March 16, 2013 [Page 1]
Internet-Draft Certificate Transparency September 2012
material or to cite them other than as "work in progress."
This Internet-Draft will expire on March 16, 2013.
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