The SRU protocol allows you to run real-time queries to external portals. Unlike the OAI-PMH protocol, the returned results are synchronous . That is to say, the same search gives exactly the same result at the same time on both portals.
Pleade implements this protocol by automatically exposing its search engine according to the SRU standard. It is also able to simultaneously interact several portals implementing this protocol. Thus, the form below illustrates the search for external portals using the SRU protocol.