Communication Protocol

[far-trader]

Originally posted by Supplement Four:
In a space combat situation, all the "pieces" will automatically be on the board...just like in Book 2 space combat.

It's the unpopluated systems (and maybe the unpopulated, less trafficed, regions of the star system) where you'll have to use your sensors to detect ships.

But, even out there, if the other ship is on the up-n-up, then it will be broadcasting with a transponder signal.

I imagine Imperial Law doesn't require a ship to broadcast with its transponder if it thinks it's in danger or could be in danger.

Correct. The way I recall it being worded is that you can and may turn off your transponder* if you believe you may attract dangerous attention BUT doing so is to be regarded as a hostile act by any ship detecting you meaning you will be the subject of a legitimate "shoot first and ask questions later" policy. Which could be more dangerous than the exuse of a possible threat of piracy against you.

* Prior to the whole Cymbeline chip stuff anyway

 

[far-trader]

Originally posted by Supplement Four:
Hmmm...

Never knew about the historical precedent. It just seemed to make sense. I mean, the practical range on Traveller comms can't be that far, in terms of a star system.

Well, in reality even the lowest Traveller ship comm is going to be far stronger both in transmission and reception capability than anything we've used in the space program to date and there is no problem communicating across the whole solar system with what we have used. Of course that's largely due to the large receiving antenna. In Traveller smaller receiving antenna will be made up for by stronger (by several magnitude) transmission power.

So, no, in practical terms Traveller comms will normally have no problem communicating clearly across a solar system.

Originally posted by Supplement Four:
Comm repeaters just seem more than practical. They seem a requirement.

Nope, they'd just add to the noise and make communications more difficult in a busy system. If anything there would be rules in place restricting busy systems to vital communications only or requiring all ships to maintain radio silence except for emergency, answering official transmissions, or operating at low power or tight beam for ship to boat and ship to shore communications.

Originally posted by Supplement Four:
The fact that there is historical precedent, combined with Traveller communication being likened to 18th century steam ship travel due to the jump drive, just seems to be poetically made for each other.

Except that the historical precedent is a totally different problem. And just beacuse is never enough reason

 

[far-trader]

Originally posted by Supplement Four:
Think of the implications, too.

Because every ship will be required to act as a comm repeater, there is no "hiding" in a modern solar system.

There is really no hiding anyway in reality when your ship is glowing in the infrared as bright as a flare star in the cold black of space

Originally posted by Supplement Four:
Every ship should automatically know where the other ship is.

So every ship will automatically know where the other ship is, by simple passive scans.

Originally posted by Supplement Four:
Combined with the ship's transponder, like blinking port/starboard lights on a sailing vessel, spouting off every second or so...no wonder sensors have never really been an issue in Classic Traveller.

Nothing other than a basic sensor package is needed if you are a merchant and you always travel to populated systems, because all other bogies are broadcasting their location via transponder pings and comm relays.

Precisely, and those transponders are... radio data. If they work without repeaters so will voice.

 

[far-trader]

Originally posted by Supplement Four:
In a space combat situation, all the "pieces" will automatically be on the board...just like in Book 2 space combat.

It's the unpopluated systems (and maybe the unpopulated, less trafficed, regions of the star system) where you'll have to use your sensors to detect ships.

But, even out there, if the other ship is on the up-n-up, then it will be broadcasting with a transponder signal.

I imagine Imperial Law doesn't require a ship to broadcast with its transponder if it thinks it's in danger or could be in danger.

Correct. The way I recall it being worded is that you can and may turn off your transponder* if you believe you may attract dangerous attention BUT doing so is to be regarded as a hostile act by any ship detecting you meaning you will be the subject of a legitimate "shoot first and ask questions later" policy. Which could be more dangerous than the exuse of a possible threat of piracy against you.

* Prior to the whole Cymbeline chip stuff anyway

 

[Supplement Four]

Originally posted by far-trader:
I don't think this will be. It just won't work.

First repeaters won't be needed at typical star system distances and situations.

Take a typical basic comm system on a typical merchant trader--say a Fat Trader.

What do you think it's comm range is?

 

[Supplement Four]

Originally posted by far-trader:
I don't think this will be. It just won't work.

First repeaters won't be needed at typical star system distances and situations.

Take a typical basic comm system on a typical merchant trader--say a Fat Trader.

What do you think it's comm range is?

 

[far-trader]

Offhand I'd say unlimited in normal circumstances.

Of course if the ship has suffered damage then perhaps the antenna are less than optimal. And if the computer is malfunctioning then it may not process the signals properly. Or if the ship is operating on emergency power then the transmission signal may be weaker.

It's no easy answer. All kinds of things can affect communications range. Solar interference. Magnetic field interference. Atmospheric interference.

And it's not just the output power of the transmitter either. A large array of antenna can pick up even very weak signals and serious computer processing can clean up very degraded or noisy ones.

If pressed for a CT game solution I'd say on a roll 12+ on 2d6 you fail to make clear linked communication. And apply DMs as follows:

-1 per range increment beyond the base detection range (150,000km for civilian ships and 600,000km for military ships) using the better range of the ships involved.

+1 per computer model number, but only on a successful computer malfunction check

-1 for standard atmosphere

-2 for dense atmosphere

-3 while orbiting a gas giant

-4 while skimming a gas giant

-1 for solar flare activity in outer system

-2 for solar flare activity in middle system

-3 for solar flare activity in inner system

-1 if operating on emergency power

+12 for Class A Starports*

+10 for Class B Starports*

+6 for Class C Starports*

+4 for Class D Starports*

* in place of computer modifiers to represent not just computers but large arrays and powerful transmitters

 

[far-trader]

Offhand I'd say unlimited in normal circumstances.

Of course if the ship has suffered damage then perhaps the antenna are less than optimal. And if the computer is malfunctioning then it may not process the signals properly. Or if the ship is operating on emergency power then the transmission signal may be weaker.

It's no easy answer. All kinds of things can affect communications range. Solar interference. Magnetic field interference. Atmospheric interference.

And it's not just the output power of the transmitter either. A large array of antenna can pick up even very weak signals and serious computer processing can clean up very degraded or noisy ones.

If pressed for a CT game solution I'd say on a roll 12+ on 2d6 you fail to make clear linked communication. And apply DMs as follows:

-1 per range increment beyond the base detection range (150,000km for civilian ships and 600,000km for military ships) using the better range of the ships involved.

+1 per computer model number, but only on a successful computer malfunction check

-1 for standard atmosphere

-2 for dense atmosphere

-3 while orbiting a gas giant

-4 while skimming a gas giant

-1 for solar flare activity in outer system

-2 for solar flare activity in middle system

-3 for solar flare activity in inner system

-1 if operating on emergency power

+12 for Class A Starports*

+10 for Class B Starports*

+6 for Class C Starports*

+4 for Class D Starports*

* in place of computer modifiers to represent not just computers but large arrays and powerful transmitters

 

[Supplement Four]

Originally posted by far-trader:
Offhand I'd say unlimited in normal circumstances.

You're saying a ship that has just left orbit of Earth can broadcast a signal toward Pluto, and the target ship in orbit of Pluto will have no trouble at all receiving the message...as long as it waites for the message to get there (a long time, even at the speed of light).

Is that what you're saying?

 

[Supplement Four]

Originally posted by far-trader:
Offhand I'd say unlimited in normal circumstances.

You're saying a ship that has just left orbit of Earth can broadcast a signal toward Pluto, and the target ship in orbit of Pluto will have no trouble at all receiving the message...as long as it waites for the message to get there (a long time, even at the speed of light).

Is that what you're saying?

 

[far-trader]

Originally posted by Supplement Four:
You're saying a ship that has just left orbit of Earth can broadcast a signal toward Pluto, and the target ship in orbit of Pluto will have no trouble at all receiving the message...as long as it waits for the message to get there (a long time, even at the speed of light).

Is that what you're saying?

Is Pluto at it's perihelion or aphelion? I'm just goofing. Yep, no trouble most of the time. Just wait between 4 to 7 hours

Double that for the reply.

 

[far-trader]

Originally posted by Supplement Four:
You're saying a ship that has just left orbit of Earth can broadcast a signal toward Pluto, and the target ship in orbit of Pluto will have no trouble at all receiving the message...as long as it waits for the message to get there (a long time, even at the speed of light).

Is that what you're saying?

Is Pluto at it's perihelion or aphelion? I'm just goofing. Yep, no trouble most of the time. Just wait between 4 to 7 hours

Double that for the reply.

 

[far-trader]

For what it's worth, our current radio noise (TV and such) looks to be good (signal still distinguishable from background noise of stars and such) for several to over a hundred lightyears. And that's after the relatively low power signals have gotten through our atmosphere and magnetosphere. Again though, I repeat, actual communications limits are much more complex than a simple range function

 

[far-trader]

For what it's worth, our current radio noise (TV and such) looks to be good (signal still distinguishable from background noise of stars and such) for several to over a hundred lightyears. And that's after the relatively low power signals have gotten through our atmosphere and magnetosphere. Again though, I repeat, actual communications limits are much more complex than a simple range function