Traveling from Starhorn to Noser through the regular route would take a few days. For this reason, transmission arrays were crucial. In the early years of the empire, small to large-scale transmission arrays were available in all main cities. Other medium-sized cities also had small transmission or transportation arrays. However, because of the previous emperor's fear of rebellion, he ordered the destruction of all arrays.
Only after Euan succeeded the throne that new transmission arrays were created, nevertheless, the location of these arrays was limited, and their route was restricted to two-way. Apart from this, the arrays could only be used with the emperor's consent.
Of course, there are transportation arrays that medium to large factions possess nowadays. But those arrays are closely monitored.
I have started showing Haylee and Euan's perspectives... hope I don't confuse you guys. Everything will make sense soon. :D