Thursday, February 16, 2017

Postel's Law again

Eight years ago I wrote:
In RFC 793 (1981) the late, great Jon Postel laid down one of the basic design principles of the Internet, Postel's Law or the Robustness Principle:
"Be conservative in what you do; be liberal in what you accept from others."
Its important not to lose sight of the fact that digital preservation is on the "accept" side of Postel's Law,
Recently, discussion on a mailing list I'm on focused on the downsides of Postel's Law. Below the fold, I try to explain why most of these downsides don't apply to the "accept" side, which is the side that matters for digital preservation.

Tuesday, February 14, 2017

RFC 4810

A decade ago next month Wallace et al published RFC 4810 Long-Term Archive Service Requirements. Its abstract is:
There are many scenarios in which users must be able to prove the existence of data at a specific point in time and be able to demonstrate the integrity of data since that time, even when the duration from time of existence to time of demonstration spans a large period of time. Additionally, users must be able to verify signatures on digitally signed data many years after the generation of the signature. This document describes a class of long-term archive services to support such scenarios and the technical requirements for interacting with such services.
Below the fold, a look at how it has stood the test of time.

Tuesday, February 7, 2017

Coronal Mass Ejections (again)

Back in 2014 I blogged about one of digital preservation's less well-known risks, coronal mass ejections (CME).  Additional information accumulated in the comments. Last October:
"President Barack Obama .. issued an Executive Order that defines what the nation’s response should be to a catastrophic space weather event that takes out large portions of the electrical power grid, resulting in cascading failures that would affect key services such as water supply, healthcare, and transportation.
Two recent studies bought the risk back into focus and convinced me that my 2014 post was too optimistic. Below the fold, more gloom and doom.