[This is preliminary documentation and subject to change.]
The generic filter will be provided in future releases of the Broadcast Architecture software. It will be programmable to match any announcement field, either as a regular or numeric expression. The disposition of the broadcast (such as receiving application, working directory) may also be specified.
This interface is currently in development, pending decisions on the announcement protocol.
The current version of the generic filter allows matching for any arbitrary line. In contrast, the ISDP interface contains specified properties including telephone, address, start time, stop time, and others. With this interface, searching is not required; instead the generic filter will contain properties that roughly correspond to those of the ISDP interface, except that search strings, rather than values, are specified.
For example, the generic filter will include a Uniform Resource Locator (URL) match string that corresponds to the session URL string in the ISDP interface. The URL match string might contain http://www.microsoft.com/*.* to indicate all files at the Microsoft site. Each of these fixed properties will have a regular expression for matching.
For extensible attributes, the a field allows arbitrary fields. An arbitrary field can contain anything. The interfaces supports as many a lines as needed. The line may take either of the following forms:
a=flag
a=attribute:value
For example, the line a=difficulty:friendly specifies friendly as the value of the attribute difficulty.