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I developed my protect schema only Bourns introduced TBU, ADI and Bourns introduced only now (http://www.analog.com/en/press-release/02_27_13_ADI_and_Bourns_Introduce_Industrys_First/press.html)
But ADI and Bourns solution don't mention about the driver common point which must have the isolation voltage above 250V according ITU-T.K21(20).
You must connect TVS diodes with the driver common point and the driver common point connect through the parallel branch of the capacitor and MOV-varistor with ground (earth). I don't recommend connect the driver common point straight ground (earth) because the capacitor current to ground (earth) would change the ground (earth) voltage and it result to losing the communication messages.
You can simply have your GND2 grounds floating. Then the ADM3053 isolation barrier alone can provide protection without any TVS, because the isolation barrier will prevent a path to earth from the bus lines for any transients.
You can have a multi-node configuration with these grounds floating, although for longer cable lengths, it may be better to connect the GND2s together to ensure the CANH/CANL signals remain in the common mode range. Even with a common GND2 connection, this doesn't have to be earthed.
Your cable shield if present, should be earthed, and sometimes this is used for a common GND2 connection where only functional isolation is required (as opposed to safety isolation of 2.5 kV). In this case where the grounding arrangement means there's only functional isolation, you might require TVS in combination with the ADM3053.