| Engineering Journal 5.5.4.1: DMS-100 switches DMS-100 switches support only two SPIDs per BRI: one SPID for each B channel. If both B channels will be used for data only, you need to configure the router for both SPIDs (one for each B channel). You cannot run data and voice over the same B channel simultaneously. The absence or presence of a channel's SPID in the router's configuration dictates whether the second B channel can be used for data or voice.