Interstellar Communication

Communication within the Highlands, and among some of the more advance Midland communities is very much based upon the existence of the hypercable communication system which is strung along the Major Routes. Worlds located in systems within transmission distance of the subspace gates or anchored hypercable relay stations have effectively instant communication with every other world on a major route.
Subspace gates provide the conduit between the hypercable system in subspace and standard transmission in real space. Most gates are either in stellar or planetary orbit. For those in stellar orbit there would often be a noticeable lag, as gates not placed in stabilized subspace must be at least 100 solar and planetary diameters away from these bodies.
So for example in the Solar System a gate would have to be located in an orbit at least 70 million miles beyond the sun. Since the minimum distance a gate would have to be from Earth would be at least 791,000 miles it could not be placed in a standard orbit, it would most likely be placed in one of the Lagrange points which are far enough to be outside the 100 diameter limits, yet close enough to ensure both minimum transit time to Earth and minimum time lag for communication carried on electromagnetic waves (radio).
Of course the gate orbiting Earth is in stabilized subspace. A hyperdrill has been used to provide a subspace conduit that allows the gate to be place within the normally exclusive 100 diameter zone. This allows  the Earth gate to be located in a geostationary orbit at approximately 22,236 miles above the equatorial Pacific Phoenix Islands.
Of course this creates another problem, which is the delay caused by the distance between Earth and the colonies in the Trans-Jupiter and farside asteroid belt.
Under normal circumstances a message transmitted from the communication array at EarthGate could require almost a hour to reach one of the moon stations at Jupiter
This problem is addressed through the use of hypercable boundary relays. A hypercable boundary relay is an unmanned station about the size of an old style bus which is place by a hyperdrill. It is place at the boundary of subspace with its body anchored to the subspace plane by a gravity anchor. Within the relay a microgate allows a transmission antenna to extend into real space. This antenna would be located within a suitable distance of Jupiter, orbiting with the planet.
So to send a message from Earth to Ganymede Base the message would be routed not to EarthGate's real space EM array, but rather through the hypercable relays already placed along the Major Route in subspace. From there it would be sent to the boundary relay, where it would then be transmitted to real space in the general vicinity of Jupiter. This results in not just effectively instant communication from Earth, but instant communication from anywhere in the Highlands.
Since for all intents and purposes everything is data the hypercable system provides the backbone for a Highland wide network of connected devices. Citizens of the Union use this network for everything from communication to entertainment. It also provides a vast repository of knowledge which is available to any world connected to the system.
But of course even in the Highlands there are many worlds not connected to the system. Worlds along Blue Highways are not hooked into the hypercable system, though it is quite possible local system wide relays might exists.
Typically worlds along Blue Highways have local networks which receive recorded data from the closest hypercable node, delivered by the Grand Postal Service. Most such systems do not have boundary relays so interplanetary communication is often plagued by time lags that make email a better communication medium than video calls. Interstellar communication is primarily via text or recorded message.
Because the network of the Major Routes do not consist of a regular pattern, but are distributed based upon world location, population, and other economic factors how a message is routed can have a significant effect on the time involved in delivering it. The Grand Postal Service spends a lot of resources determining the routes which will result in the fastest delivery of message sent to disconnected worlds.
This disjointed system often results in news being delivered almost or more rapidly by private or commercial vessels before official news organizations. Both Church and government maintain couriers in an attempt to stay ahead of rumor or even official news.

Food Fabricators

A food fabricator is a device that uses nanotechnology to produce edible objects from an organic feed stock. On world food fabricators are used to supplement naturally grown and process foods. On spacecraft and stations food fabricators produce almost all of the food consumed. Most food fabricators can also be used to prepare natural food, at least to a limited extent.
The typical industrial food fabricator, such as might be used in a restaurant or mess deck consists of a feed line of liquid organic feed stock, a potable water line, power coupling, a recycle intake, a print stage/extruder, heat pump assembly, LCP, network connection, solid stock input (for natural or processed food), and a control panel. The device is typically connected to a central database of food recipes.
The device operation is as follows:
The user selects a drink or meal using the control panel for an item listed in the database. The LCP initially orders the device to provide the designated container for the meal. this may be a plate, bowl or cup for liquids. The exact design of the receptacle is selectable by the user, or a default item may be used. The container is extruded. It will be constructed of an organic plastic by the fabricator. Alternatively an existing cup or plate may be refilled by placing it on the stage.
Meanwhile complicated ingredient creation will begin. The fabricator is capable of creating both raw and "cooked" versions of foods. Some food, like faux flesh is better produced in its raw version and then cooked through heating. Other foods like starches (near potatoes, pseudo rice, and pastas) are better produced in their cooked forms and then heated.
The heat pump assembly places the food at the proper temperature for serving. It can also cool drinks or serve them hot. Once completed the food or drink is placed or poured into the extruded container.
The food fabricator is better at producing certain kinds of foods rather than others. For example hamburgers or chili is much easier to produce than steak. Chicken is much better in Ratatouille than in sauteed chicken breast, as the breast almost never comes out with the same texture as real chicken. The device won't make chicken drumsticks or wings at all, since fabricating bones to be later recycled is not a good use of resources.
For drinks, water is combined with the organic feed stock to produce coffee, tea or soft drinks. Alcoholic beverages are also possible, though simple mixed drinks are generally considered better tasting than beers, wines, or whiskeys which generally get their character from complex trace elements normally created in their natural brewing or distillation process.
Spices are usually prefabricated in the device and then used to season to the taste of the user.
Once the meal is finished food waste and tableware are then thrown in the recycling intake where it travels to the reclamation plant and joins the human waste provided by the fresher systems to be converted into organic feed stock to be reused by the fabricator systems.
Smaller convenience food fabricators, which are located in staterooms, conference rooms and convenience drink dispensers, often located in hallways and control areas, typically have a smaller selection of offerings, typically to reduce the time between delivery, as it takes only seconds to create a coffee or pack of pseudo carrot snacks, but ten minutes or so to make a complete meal consisting of meat, starch and vegetables. A typical industrial food fabricator can make a dozen meals at the same time, a convenience unit usually only one at a time.
Some industrial units are self serve, but often for sit down meals a range of similar dishes are fabricated to be served by household drones once everyone is seated. In that case food is stored in heater boxes or refers between when it is fabricated and when it is served.
 In a pinch a food fabricator can be used to synthesize other kinds of organics, but it will typically take hacking its LCP to do that, since there are food quality and safety protections built in.

Advanced Smart Materials

Compound smart materials are advanced smart materials which can exhibit the properties of more than one kind of smart material in a single material sample. This allows for the creation of more complex devices which can take advantage of the smart characteristics of more than one kind of smart material property. So for example one can have a set of shape-memory sunglasses which exhibit chromogenic properties. Or a photomechanical  material that has magnetostrictive properties.
Complex Compound Smart (CCS) materials can be used to make very complex devices, such as extruding space helmets which contain Heads Up Displays (HUDs) or space activity suits which use smart material to provide mechanical counterpressure when external pressure drops, but also provides comfortable temperature regulation in both normal pressure and vacuum environments.
CCS materials are a product of nanotech factories and are made using material fabricators. 

Legion Shipsuit

The Legion Shipsuit is an example of high tech field dress used by members of the Legion serving on board spacecraft. The shipsuit is a high end skinsuit worn by legionaries engaged in shipboard duties as a regular working uniform. As a uniform it is typically manifest as a black uniform with silver trim adorned with rank insignia and specialty badges for enlisted members. The chameleon surface can be altered under the control of the suit LCP (Local Control Processor) when circumstances warrant, such as to bright orange in rescue situations or woodland pattern when in the field planetside.
Suit control is effected through the touch display located on the suit's left sleeve. Certain suit functions can also be activated using touch switches located at certain points of the suit, for example a collar switch can be used to activate the helmet extruder.
As a high end skinsuit the Legion shipsuit includes the ability to extrude an airtight helmet and gloves for vacuum survival. The helmet includes a heads-up display (HUD). The suit has integrated communication and while it does not have it's own full sensor suite it can interface with internal ship's systems when worn on a Legion spacecraft or a CMC. It does have minimum temperature and atmosphere safety sensors, a multi-spectrum vision system and both general and spot lighting capability.
While not meant for use in high radiation environments, being an IVA (intravehicular activity) suit, shipsuits do contain both a low-g B/G harness useful for propulsion in microgravity and micro-g boots. This is to enhance their capability in shipboard damage control situations.
The suit is intended for use in the field in a wide range of habitable environments and so contains both an integrated heating and cooling system and the ability to extrude a cold weather hood.
Like most skinsuits the shipsuit contains a  re-breather  pack and a mini tank which gives 30 minutes of air. They also have an external connection to allow use with a small tank giving 12 hours of air or a fixed system for virtually unlimited air.

Smart Materials

The term Smart Materials encompasses a class of designed materials whose properties can be significantly changed by controlled external stimuli. The first smart materials were developed during the Progressive Era. The range of smart material properties is extensive.
Smart materials are used extensively in the technology of the Grand Human Union and in many of the Midlands and even some of the Wilds. Programmable matter is a type of smart material that is used extensively in spacecraft construction, clothing, and instrumentation.
Smart material can change its shape, conductivity, optical properties, moduli, density, electrical properties and even it's magnetic and gravitic properties.
The use of smart material allows for operational behavior of devices that would seem almost magical to generations who lived before the Progressive Era.
Some use of smart materials has already been mentioned. For example in airlock construction, vacc suits and cybersuits.

Space Combat extended

Space combat was been lightly covered in previous posts. Within the Highlands any ship-on-ship actions are primarily single ship-on-ship police or anti-piracy affairs conducted primarily by Ranger units on corvettes or schooners. From time to time a Frigate patrolling the border between the frontier and the Midlands might find itself engaged by a foreign vessel or multiple hostile vessels of a subordinate class.
Outside the Highlands, in the Midlands or the Wild large scale squadron, task force or fleet battles are much more likely. Such combat is very much different in scope and character from  single ship actions. While a Frigate embarks support craft and might deploy pinnace to act as scouts or pickets or even have fighting vehicles or battleriders to act as support craft they typically do not have the long range reconnaissance or Command and Control systems necessary to engage in fleet level actions.
During one-on-one actions vessels typically depend upon their own sensor suites to locate enemy vessels, direct fire control and engage enemies.
During fleet actions major combatants, such as dreadnoughts and superdreadnoughts use pickets made up of destroyers and battleriders to deploy sensor nets, act as forward firecontrol nodes and provide support. To aid in this role destroyers tend to be light on energy weapons, but heavy on missiles. They primarily use railguns and light lasers in the anti-missile roll. Destroyers are small enough to employ relatively effective stealth and cloaking technology, like the more heavily armored battelriders.
In real space combat even the most powerful energy weapons are limited to 300,000 miles range. In subspace their range is a twentieth of that. At those ranges sensor response lags only a second. Missiles are effective at distances far beyond the range at which sensor response lags by minutes. Sensor nets can also be effectively deploy at distances which result in information minutes or hours old being the most recent data upon which response decisions must be made. Likewise large dispersed sensor nets can detect objects at distances so great that the information is an hour and a half old by the time the information reaches its control node.

Divergence

As originally stated though the background for New Diasporia can be applied to any game system, the game itself was developed using GURPS, primarily 3rd Edition, especially some of the Traveller rules, but also GURPS Space. Here and there other GURPS source book rules are used. Some rules come from GURPS 4th Edition, though modified for use with the 3rd Edition rules.
I have also stated that there are fundamentals of the GURPS Rule set, primarily in Tech Levels, Tech Level advancement and maintenance rules which have been modified, primarily to support the background but also because they don't work reasonably as originally constructed.
During the original playtest for GURPS Traveller it was noted that the rules for missiles and spinal mounts resulted in missiles dominating, a circumstance that did not well reflect the original Traveller material. Several rule modifications were introduced to mitigate this, but resulted in other problems vis a vis ship survivability against spinal mounts.
In New Diasporia this is not so much a problem. Traveller Meson weapons do not exist and particle weapons are primarily relegated to close support planetary use. While Laser and Grazer weapons are used, especially in the close support and anti-missile roles space combat is dominated by missiles.
That is real space combat is dominated by missiles. Subspace combat is another story. In subspace missile drives propel a missile not faster than other B/G powered vessels, making missiles ineffective. Subspace combat is heavily dominated by energy weapons which have very much reduced ranges, just as do sensors.
A variety of energy weapon sizes are available for use on spacecraft. Lasers and Grazers typically mounted in turrets (1500 cuft for turret space, 500 cuft for mounts and rotation space.) New Diasporia turrets typically do not contain crew spaces. Weapons may also be mounted in barbettes. Barbettes come in 2500 cutft and 5000 cuft versions which require 500 cuft and 1000 cuft of internal volume for mounts and rotation space respectively.
Smaller turrets can also be used for close support weapons (which in Traveller are called planetary weapons), but such weapons are typically only mounted on battleriders and small craft like pinnaces.
Weapons may also be fix mounted. Missile tubes may be fixed mounted individually or they may be mounted in missile bays. Missile bays typically come in 25,000 cuft and 50,000 cuft sizes. The difference in fixed mounted weapons and weapons mounted in a bay is that a weapon bay includes a targeting computer and laser communications links sufficient all of its launchers. Fixed mounted weapons must use an external computer with the proper software and a separate communication suite, which is probably mounted in a turret somewhere.
It is also possible to fix mount an energy weapon, but only the battleriders use spinal mounted energy weapons, typically heavily supplemented by missile tubes for use in the anti-missile role. A fixed mounted energy weapon cannot be used in the anti-missile role.

Monitors and Forts

So one might say, if the Grand Human Union is such a peaceful, benevolent place why does the Star Legion have such devastating firepower as embodied in First, Second and Third Raters?
The answer is monitors and forts.
A monitor is a 10 to 30 million cuft warship. They are heavily armored with force fields and armed with massive energy weapons and missile launchers. Unlike battleships they typically do not embark battleriders or troops. They also typically do not have shunting capability. That means that they are limited to accessing subspace using a gate.
That means that monitors are used as both system defense ships and gate defense platforms.
The development of the battleship was a direct result of the deployment of monitors which greatly outclassed the frigates and battleriders that existed at that time.
However dreadnoughts and superdreadnouths were a response to the even larger and more powerful forts developed to defend systems.
A fort is a grav powered installation typically grav anchored on the subspace side of a gate or in orbit near the real space side of a gate. With BG engines typically only within the 4 to 6 g range a fort can move only sufficiently to move to its place of station and make a poor target for ballistic weapons (like unpowered missiles.) Because it does not have to mount a powerful BG engine a fort is not limited to 250 million cuft. As a matter of fact it usually mounts more powerful force field armor than all but the most powerful superdreadnought as well as having a massive structural frame supported by structural integrity fields and physical armor as well as internal armor force fields.
Forts also typically mount massive energy weapons, missile launchers (for use in real space) as well a numerous battlerider squadrons. Forts are often located near each other where they can provide mutual fire support.
Like other combat vessels forts deploy either sensor drone nets or purpose built sensor arrays to enhance their abilities to detect incoming enemies.
Enemies who defeat gate defense forts often find themselves facing another layer of defensive positions on the far side of the gate in real space.

Subspace Combat

In subspace combat the nature of the environment makes missiles useless. No matter how good their engines a missile effectively travels no faster than any other vehicle. This makes them easy prey for energy weapons.
Like missiles, railgun projectiles are really just matter enhanced with gravitational engines. They tend to lose momentum quickly and become ineffective at any kind of range.
Energy weapons ranges are drastically reduced, but their effectiveness within their useful range is unimpaired. Typically energy weapon ranges are reduced by 20, that is they are half as effective as they are in normal atmosphere.
Force fields are just as effective in subspace as in real space, but as a gravitic phenomenon are less detectable in the high gravametric environment of subspace. In other words a ship protected by a standard force field is harder to detect. Against the high gravometric background of subspace force field stealth technology is less effective.
On balance this makes it hard to detect protected warships at greater ranges, but distortion fields and masking are less effective at close ranges.
The heavy electromagnet interference in the subspace environment makes long range and active sensors not nearly as good as in real space. This is one reason road beacon stations are seeded so close together and why off road vehicles and ships must depend upon inertial navigation and gravitational topology plotting and can only detect subspace beacons when they are fairly close to the system that has anchored them. This also makes the kinds of weapon ranges seen in real space battles untenable in subspace. Because of the high EM background EM masking and stealth become more effective.
Once away from the beacon stations of the Major Routes and Blue Highways accidentally meeting another vessel is unlikely. So battles in subspace tend to occur at gates or near system beacons. Of course this is where systems concentrate their own defenses when they expect an attack as well as where standard defenses are anchored.

Extensible Hulls

Small craft, such as brakes and HUVs often use extensible hulls to maximize usable space while in space or on the ground, yet allow for a more streamlined shape while transiting atmosphere. Extensible hull craft also allow for smaller hanger footprints while being carried aboard larger craft. They also sometimes allow hull compact enough to use transport portals, a reason many brakes and HUVs are held to 8 ft by 13 ft. cross sections to allow their use in standard 10 ft by 20 ft transport portals.
Slide compartments are skinned in hull sheets made of smart material that can expand to allow the underlying structure to slide out while maintaining an air tight envelope. The use of structural integrity fields allows both greater stress to be tolerated by the sliding section and helps maintain airtight integrity.