Hi, you want know about the difference between SDS and SMS. First, the SDS (Short Data Service) belongs the TETRA network. This network is used by the police, army, firemans... Unlike SMS, which belongs the GSM network for civilians. Then, the SMS can just carry text where as SDS can carry many applications like voice, GPS location. I found these informations in this link. https://www.tetra-consultancy.com/index.php?/TETRA-network-services/short-data-service-sds.html
I hope it can help you:wink: