I see the transponder issue as being one of not guaranteeing security but making it *difficult* for wrongdoers - within the Imperium at least.

I was thinking that the transponder would be the key element, set up and sealed by the starport authority with a variety of anti-tamper mechanisms whose job is not to stop unauthorised access to the box, but to render it unusable if you do (including destroying the storage that contains the keys). That makes it *difficult* for anyone to get hold of any private keys - but not impossible (the corsair, for instance, is described as having a transponder that can be switched between several IDs). 

As Catherine said, the authorities are going to maintain a separate database of public keys for verification. I see that as being for double checking rather than an intrinsic part of the system, though. After all, if you have the valid key pair for more than one ship of the same class then you can pretend to be any of them and no external database is going to spot that. I do like the idea of the handshake computation problems though, to try and establish that the unit broadcasting the signal is a real transponder (or at least a very, very good fake).

Depending on where you are and who is checking on you, the response from the authorities is likely to vary from a casual once-over, through boarding your ship, to shooting on sight for any infraction.

Of course, being caught using different transponder codes is going to get you treated as a suspected pirate at best...



On Wed, 3 Apr 2019 00:39 Phil Pugliese (via tml list), <xxxxxx@simplelists.com> wrote:
With the plethora of various & assorted polities thruout known space, I've always DGP's 'transponder doctrine' to be, at best, impractical.

I just can'r see all those vargrs really caring very much & then there's the pirates.

Since we know that piracy is still present, despite all the attempts to 'eradicate' it here on the TML & elsewhere, just use whatever technique they use.

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On Tuesday, April 2, 2019, 6:14:11 AM MST, Bill Rutherford <xxxxxx@comcast.net> wrote:


All,

In canon, can a ship record another ship's transponder broadcast, and
rebroadcast it, essentially taking over that ship's identity?

I've found very little online and the only printed reference that
discusses it much at all is the Starship Operator's Manual Vol 1,
published by Digest Group back in 1988.  Their "short version" is
that the transponder is in an essentially unbreakable black box that
requires a licensed technician to reprogram (i.e. change the signal
being sent).

One of my players is intent on sending a bogus transponder signal but
doesn't want to go so far as altering the black box.  His plan is
"harvest" a transponder signal sent by a random ship after turning
off his own ship's black box.

So - back to my original question, would this work?

One obstacle I can think of would be if the transponder sends some
sort of authentication code based on a "seed" of some sort (kind of
like the way a Symantec cybertoken uses a random number seed only
elsewhere held on a Symantec server somewhere) which would be more
difficult than most would be willing to deal with - to duplicate.

What other obstacles, other than saying "That's now how they
work!  You cannot rebroadcast somebody else's transponder signal
because the Imperium, in their wisdom, incorporated handwavium into
the transponder that precludes this sort of thing" might there be?

In advance, thanks!


Bill Rutherford

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