What is the difference between the ‘push’ and ‘pull’ communication methods for a dataset?
Push and pull are technical terms that are used in the metadata field ‘Communication method’ on the resource level of a dataset or service. More specifically, the difference between these terms lies in the manner on how the dataset or service is transferred between the data provider and the data user:
The communication method ‘push’ implies that the data provider delivers the dataset or service to the data user on its own initiative, a situation that occurs rarely in practice. In this case, an agreement for data delivery is often established between the data provider and the data user. The communication method ‘push on occurrence’ is a specification of the push method and means that a push takes place at specific moments in time, e.g. when an update of the underlying dataset is published by the data provider.
The communication method ‘pull’ means that data users consult the dataset or service themselves according to their needs. In practice this means that the data user consults the datasets on the NAP ITS on the moments he/she desires. The data provider does thereby not notify the users when an update of the underlying dataset is published. Given the NAP ITS is designed as ‘yellow pages’ with links to the datasets and services, the pull method occurs most frequently.