The prospect of Smart Grid (SG) is becoming a reality in the recent years, covering different areas like smart metering, demand side management, or distributed generation. Communications play a central role in the SG architecture, because the power utilities need to collect important information to make optimal decisions for efficient power generation, transmission and distribution. This paper discusses the state-of-the-art of narrow-band high-speed power line communications (PLC) - a promising communication platform for SG which offers advantages in coverage, costs and availability. Further, the paper presents an overview of DLC+VIT4IP (Distribution Line Carrier: Verification, Integration and Test of PLC Technologies and IP Communication for Utilities) a EU funded project under the 7th Framework Programme (FP7) that aims to extend the existing PLC technologies by developing efficient transport of IPv6 protocol, automatic measurement, configuration and management, and security. In addition, the project is exploiting frequency ranges up to 500 kHz, to support systems serving larger smart grid applications.