must transducer be connected to data master?

I am installing an eS127 and an eS78 connected via Ethernet/seatalkHS. There is also a NMEA 2000 spur connected to the eS127. Two questions:

1. Is it necessary for the NMEA 2000 network to be connected to the data master?

2. Must the depth transducer be connected to the data master?

thanks