Introduction

This chapter is devoted to the third of the basic principles for a metadata strategy that were outlined in Chapter 3, ‘Ensure interoperability’. As was shown there, an ideal state of interoperability would allow metadata to be exchanged with others without requiring any modification or manipulation; this demands more of it than interchange, which does require actions of this kind if it is to be comprehensible to the receiving system. To achieve interoperability requires a degree of congruence between the donor and recipient at two levels: syntactic, a mutually comprehensible encoding format; and semantic, an agreed set of meanings attached to metadata components which allows them to be understood by both parties.

Syntactic interoperability is best assured by the choice of XML as the encoding format for metadata. Its independence from specific software packages, its use of the universally decodable format of text as its foundation and its ability to combine the machine-processable and human-readable should ensure that metadata is comprehensible at a syntactical level when it is ingested into another system. The more demanding challenge is to enable the dialogue between two collections to operate in the semantic sphere as easily as in the syntactic.

We will have already made this easier by applying the other principles that have been followed throughout this book. Using standards whenever possible (Principle 7) is the most obvious of these: employing a metadata standard inevitably entails the adoption of a set of semantics that are known to and applied by others in a community. Controlling metadata content whenever possible (Principle 4) and imposing a logical system of identifiers (Principle 6) also assist here, the former by ensuring the consistent use of shared semantic schemes such as name and subject authorities, the latter by enabling the precise identification (for instance by URIs) of every metadata component. Ensuring software independence (Principle 5) enables metadata to transfer across systems on different platforms and ensuring the integrity of the metadata itself (Principle 8) makes it easier for others to trust its accuracy and authenticity.

The strategy outlined in this book and the principles that underlie it should, therefore, go a long way to rendering any metadata interoperable with others.