It appears that many of these sets are obsolete and that work is required to incorporate the newer standards. A potential incompatibility arises in the attribute sets supported by servers. However, so far only the bib-1 set has been defined and thus the problem has not been encountered. 2.3 Character sets Another area of potential difficulty in the interoperation of bibliographic systems is in the character sets used for the data. These provide a 16-bit character set which allows the representation within a single character set of enough symbols to display all modern languages together with a large variety of punctuation and special characters.
Further difficulties arise in the interpretation of queries.
It is not easy to convert a query received in one representation to another for carrying out a search. There are also difficulties with collating sequences because of different national conventions, even when a compatible character set representation is used. 2.3.1 Character sets in Z39.50 During the early part of 1994 there was a detailed discussion on the mailing list of the Z39.50 Implementors Group concerning support for character sets in future versions of the standard. As a result of this and discussion at meetings, there is an effort to incorporate extensive support for multiple character sets in Z39.50, with negotiation between origin and target possible. The major issue is to identify those areas where support is required.