Stephan Neuhaus <neuh...@st.cs.uni-sb.de> writes: > For business reasons, > Alice can't force Bob to use a particular TTA, and it's also > impossible to stipulate a particular TTA as part of the job > description (the reason is that Alice and the Bobs----great band name > BTW---won't agree to trust any particular TTA and also don't want to > operate their own).
You don't need such a complicated description -- you're just asking "can I do secure timestamping without requiring significant trust in the timestamping authority." The Haber & Stornetta scheme provides a timestamping service that doesn't require terribly much trust, since hard to forge widely witnessed events delimit particular sets of timestamps. The only issue is getting sufficient granularity. Perry --------------------------------------------------------------------- The Cryptography Mailing List Unsubscribe by sending "unsubscribe cryptography" to majord...@metzdowd.com
