The Portal Delta was a type of navigation computer.
The Portal Delta was very glitch prone and required constant maintenance. It would shut down when activated due to an inherent design flaw, unless the user could work around it. Furthermore, once shut down, it could take a number of minutes for the restart sequence to boot it back up again.
The shipwright Suwantek Systems usually subcontacted the task of making navigation computers for its starships to the companies Industrial Automaton and Fabritech. However, when designing their TL-1800 freighter, they decided to cut costs by developing their own computer, the Portal Delta. However, the Portal Delta performed poorly in comparison to other navigation computers and news of this inferiority spread at around the same time that sales of the TL-1800 peaked. This caused sales to dip, so Suwantek realized their mistake and replaced the Portal Delta with a Fabritech navigation computer on all future TL-1800s that they built. Many owners of the earlier TL-1800s replaced their Portal Deltas with different navigation computers or astromech droids, but a few continued to retain the original computer.