Heya guys facing a big problem here ... we need to deliver a lot of messages to customers (re-marketing) at around of 50K messages per day. Using gsm modems is not an option, using 3rd party sms gateways like twilio, plivo, nexmo its not an option as well as they slowly kick us out due to lots of messages and carriers blocking their pool of numbers. So as i had oportunity to find out those sms gateways use SMS Enabled VoIP DIDs for sending the messages. My question is: How can we build similar solution to theirs, using SMS Enabled DIDs, what voip software to use, where to get that kind of DIDs, are those DIDs with free SMS plans or its included into monthly subscription or its pay per sms cost, and some guides on how to build entire system. we specifically need this for personal usage.