The Higher Propulsion.

Extract from Space technology - published 2560.

The omega war had devastated the galaxy, rendering conventional forms of propulsion - transwarp, Quantum Slipstream drive and warp drives useless.

Research into solving this dilemma, particularly the new drive of Starfleet and the Federation to exploit and expand in order to survive, went two ways. One option was to find a way to fold what was left of subspace on itself and traverse space that way, thereby avoiding the damage.

It was shelved when a propulsion system using a system that didn't involve subspace came along. It was so practical it avoided the issues of normal space travel.

Travel in hyperspace.

Hyperspace fell into the category of higher propulsion technology. The Federation and, indeed, other races, avoided the needs for the higher dimensions.

With this technology, the Federation, which, by this time, had become more and more imperialistic, started spreading across the cosmos faster than subspace travel would've let them.

Hyperspace worked by simply opening a portal along a wormhole, allowing the ship to traverse distances in less than a second. Anyone using hyperspace would be able to travel as far as they want instantaneously.

Ships underwent a vast redesign, no longer were warp nacelles needed, now ships became more larger, less fragile and without the need for two separate hulls.