In case you are planning for migration via DIA or IPVPN link and as example you have 200Mb stable speed so you could calculate using the below formula. (( 200Mb /8)x60x60x24) /1024/1024 = 2TB /per day In case you have different speed you could replace the 200Mb by any rate to calculate as example below. (( 5 00Mb /8)x60x60x24) /1024/1024 = 5.15TB /per day So approximate each 100Mb would allow around 1TB per day.