COMMUNICATIONS

Spaceships always have communications equipment. Radios, lasers, and similar devices send information by modulating electromagnetic information. Advanced societies may manipulate gravity waves or neutrino bursts to communicate.

However, all of those methods are

limited to lightspeed. Adequate for communication across interplanetary distances, they become very slow and cumbersome at the interstellar level. If FTL travel exists, then FTL communication may exist – but the GM will want to carefully consider how such communications work.

No FTL Radio

If no FTL communication is possible, then the speed of communication becomes that of the fastest starship. Fast courier ships will maintain contact between worlds, carrying mail, news, and government dispatches. Slower ships, possibly independently owned, will contract for mail service to less important worlds. Without FTL communications, invading fleets, escaping criminals, and similar menaces may be able to outrun the warning that they’re coming.

Without FTL communication, interstellar trade is risky; a merchant won’t be able to determine in advance what the target market needs. A trader who guesses right can get rich, while one who guesses wrong will go broke. If the interstellar state is large enough that it takes months or years to cross by starship, then the capital will seem remote and people will tend to be more loyal to their world or province than to the state as a whole. Military forces will need to be large and scat- tered, so that there is always enough force at any point of danger. Military commanders will have great leeway when they are far from superior authority; bravado and strategic skill will be very important.

Slow FTL Radio

Slow FTL communication – say, three or four times as fast as the fastest starship – helps tie an interstellar state together. However, FTL “radio” may be expensive; perhaps it takes up too much space or requires too much energy to be installed on a starship. In this case, FTL communi- cation may take place only between the most important worlds, while ships and minor worlds still have to rely on couriers. Access to FTL communications will be a great advantage for merchants, or for military commanders.

Fast FTL Radio

Fast, cheap FTL communication makes it easy to hold an interstellar state together. Trade becomes relatively safe, as merchants can easily check the market at their destinations before they even load cargo. Military fleets can be smaller but still used efficiently, since they can quickly be called together in an emergency. On the other hand, merchants and military officers alike will find their freedom of action limited, with superior authority always an FTL call away. Captains will rarely take action without referring to HQ for orders!

If FTL communication is this easy, the GM may want to impose limits on it to make sure that it can’t ruin a dra- matic situation. FTL “radio” may have a limited range, forcing the state to set up “repeater” beacons and ensuring that a ship out on the frontiers can’t call home. Communications may be unreliable, with “static” or some other blockage appearing at appropriate moments. Or perhaps messages are still delayed enough in transmission that a call for help can’t be answered immediately!

Bandwidth

Another factor to consider when designing FTL communication methods is bandwidth. Bandwidth is a technical term, describing how much information can be sent through a channel in a given time. A communication method can be extremely fast and almost impossible to jam – but if it takes many hours to transmit a message even a few words long, it won’t be as useful!

A fast but low-bandwidth communications method can have interesting effects on the campaign setting. It may be easy for a spaceship to maintain contact with its home base, but not to send detailed messages or ask for extensive information. If the transmitter is too bulky for a spaceship to carry, then it can receive orders or bulletins from home base without being able to respond. Interstellar communications will be expensive, and may be metered by the word (or the byte) like old-style telegrams.