DPI, or deep packet inspection, is a type of network data filtering. This process can locate, detect, categorize, block, or reroute data packets that contain specific codes or data payloads. The process is both good and bad. It can prevent worms, spyware, or viruses from entering a corporate network, but it can also be used for eavesdropping and censorship. IP blocking on the other hand is the banning of outside connections for certain IP addresses. If a website decides to ban your IP address, you will no longer be able to access it - unless you use a VPN to help change it.