# MSPP filters

Each MSPP connection consists of a linked set of MSPP filters. An MSPP filter is a task or process that performs an operation or set of operations with data that flows through it. All MSPP endpoints and channels are made up of one or more filters that perform specific tasks with the data they receive. Cumulatively, these filters carry out all the tasks performed by the endpoints and channels that make up the connection. The following illustration shows the channels that make up a typical voice channel:

MSPP endpoints and channels use filters in the following way:

- Endpoints are made up of a single filter that translates data between a network specific transport format (for example, DS0 or IP format) and a media-specific format (for example, T.38 fax, G.711 voice).

- Channels consist of one or more MSPP filters that perform specific tasks with data as it moves from one endpoint to another.

Applications can use MSPP API functions to send commands and queries to the filters that make up standard MSPP API components (endpoints and channels). For more information about MSPP channel and endpoint filters, refer to the Dialogic® NaturalAccess™ Media Stream Protocol Processing API Developer's Manual.