workings of trust signatures

[Christoph Anton Mitterer]

Hi.

I just wanted to fresh up my knowledge on trust signatures and have it
confirmed whether I've understood it correctly.

So first of all, level 0 TSigs are identical to normal non-trust-sigs.

e.g.:
[my self] --normal sig--> [person A] +-normal sig--> [person B]
                                     `-trust5 sig--> [person C] --normal sig--> [person D]

=> I only trust A,.. but nothing "below" A (at any level).



Level 1 TSigs would mean, that I signed that key (as with normal
signing) but in addition I also trust (with the specified value 60 or
120 e.g.) keys he signed (regardless of whether he used a normal sig or
a TSig for that.

e.g.:
[my self] --trust1 sig--> [person A] +-normal sig--> [person B]
                                     `-trust5 sig--> [person C] --normal sig--> [person D]
                                     `-trust5 sig--> [person E] --trust2 sig--> [person F] --normal sig--> [person G]

=> I only trust A, B, C and E,.. but nothing "below" B, C or E (at any level) because of my own level 1 tsig to A.


If I give higher levels of TSigs... the level is always the maxmium number of hops that can occur,..
But only further Tsigs on the keys I've signed with it,... will make this usable,.. so it cannot jump over normal sigs:

e.g.:
[my self] --trust6 sig--> [person A] +-normal sig--> [person B] --normal sig--> [person C]
                                     `-trust5 sig--> [person D] --normal sig--> [person E] --trist1 sig--> [person F]
                                     `-trust1 sig--> [person G] --trust5 sig--> [person H] --normal sig--> [person I]

=> I trust
- A
- B (because of my trust5 sig to A)
- not C as, B signed it only with a normal sig
- D
- not E or F (even though my own trust to A and the trust from A to D
were H, but D didn't sign E with a trust sig, the fact. that E signed F
with a trust sig is irrelevant, as there was a "hole" in the chain
- G
- H
- but not I, as G was only given a trust1 sig by A

Right so far?

So the chain of trust sigs can be "aborted" at any level, by a signature
"before",.. even if signatures that came even more earlier specified a
high enough level.



Thanks,
Chris.


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