Re: [ARSCLIST] Hard disk drives and DAT

["Richard L. Hess" <arclists@xxxxxxxxxxxxxxx>]

At 06:51 AM 2007-03-27, Tom Fine wrote:

> What's an "MD5 hash"? Also, what do you mean by "community"?

MD5 Hash is a type of checksum like CRC and others. Some consider it 
the preferred checksum for large files.

One of the things with the astoundingly low bit error rates (BER) of 
modern storage is you may never see one, but statistically they can 
occur. MD5 and other checksums permits you to catch even these rare events.

Community is part of the hierarchy of the D-Space software. Within a 
D-Space instance such as Univ of Toronto's T-Space, there are 
multiple communities.

Within a community there are optional sub-communities.

Within each community or sub-community are a list of collections.

Within each collection there are items.

Within each item are files.

The items can be assigned to multiple collections without repeating 
files. Only the metadata is repeated.

D-Space as implemented at UofT is, I believe, OAIS compliant. It's 
primary metadata schema is Dublin Core, however they are currently 
permitting other metadata schema as well.

Here is the list of all available metadata fields within the D-Space 
implementation of Dublin Core.
http://www.dspace.org/technology/metadata.html

Cheers,

Richard

Richard L. Hess                   email: richard@xxxxxxxxxxxxxxx
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