This communication network is the only way for humanity to maintain contact between star systems.
The Transit Rings are the communication nodes for the HubComm.
In established systems with a transit ring, there is a comm relay built into the ring. It will open a tiny portal and send data in the form of radio/microwave emissions to another target ring.
All of the rings are linked together in a network. To allow for incoming emissions, all of the rings will open those tiny portals at regular intervals of 30 minutes.
If a priority transmission is sent, the interval can be temporarily adjusted between two rings. In some cases, those portals will be maintained to allow for real time communication.
Rings are located at a planet’s L2 point. So planet-to-planet communication in “real time” has about a 10 second delay, each way.
In systems without transit rings, they are wholly dependent on spacecraft to relay information. While rare, it does happen.
Many habitable worlds in human space had a ring built near their primary planet during the earlier eras.
Military vessels operating away from habited areas use dedicated courier ships to maintain communication with their chain of command. Most combat vessels do not have their own Hub Drives. Either piggybacking with a Transit capable ship or using transit rings.
Civilian ships almost never have Hub drives and are reliant on the transit rings. This makes civil inter-system communication without the rings, nearly impossible.