Indicates types of calls to be filtered by this
call discriminator definition.
This object is a bit map, with each bit representing
a different call type as identified below.
A 1-bit indicates that call type is filtered.
A 0-bit indicates that call type is not filtered.
Bit 0 - Digital
Bit 1 - Speech
Bit 2 - V.110
Bit 3 - V.120
Setting all defined bits to 1 would result in all calls
being rejected by this call discriminator.
Setting all defined bits to zero would result in all
calls being accepted by this discriminator.