Dimensional drive

A dimensional drive was a form of rudimentary faster than light propulsion that was invented and used by humans in the time before the founding of the Republic.

History
This type of propulsion worked by rippling space-time such that faster than light velocities could be achieved. Still this type of propulsion was not nearly as fast as hyperspace travel and for longer trips crews needed to be placed in suspended animation via carbonite freezing. This technology was used to get Sleeper ships from Coruscant to planets like Kuat, Alderaan, and those in the Tion Cluster for the purposes of colonization.

Behind the scenes
The method in which this type of propulsion works sounds very similar to that of Warp drive from the Star Trek series.