- The &yaz; toolkit offers several different levels of access to the
- Z39.50 and SR protocols. The level that you need to use depends on
- your requirements, and the role (server or client) that you
- want to implement.
- </para><para>
- The basic level, which is independent of the role, consists of three
- primary interfaces:
+ The <ulink url="http://www.indexdata.dk/yaz/">&yaz;</ulink>
+ toolkit offers several different levels of access to the
+ <ulink url="http://www.loc.gov/z3950/agency/">ISO23950/Z39.50</ulink>
+ and <ulink url="http://www.nlc-bnc.ca/iso/ill/">ILL</ulink> protocols.
+ The level that you need to use depends on your requirements, and
+ the role (server or client) that you want to implement.
+ If you're developing a client application you should consider the
+ <link linkend="zoom">ZOOM</link> API.
+ It is, by far, the easiest way to develop clients in C.
+ Server implementers should consider the
+ <link linkend="server">generic frontend server</link>.
+ None of those high-level APIs support the whole protocol, but
+ they do include most facilities used in existing Z39.50
+ applications.
+ </para>
+ <para>
+ If you're using 'exotic' functionality (meaning anything not included in
+ the high-level APIs), developing non-standard extensions to Z39.50 or you're
+ going to develop an ILL application you'll have to learn the lower
+ level APIs of &yaz;.
+ </para>
+ <para>
+ The basic low level modules, which are independent of the role
+ (client or server), consist of three primary interfaces: