SDN promised to free us from the tyranny of legacy protocols and incumbent technology vendors. However, despite considerable research interest over the past five years, SDN still remains constrained by protocols and its commercial adoption is very slow. In this talk, I will discuss the main technology, standardization and business barriers that are hampering widespread adoption of SDN technologies. I will also share customer-driven ideas on how SDN technologies should be architected and delivered in mission-critical networking markets.