9 word electrum seed creates same wallet as 11 word ?!

[wingsuit]

If you restore from seed with these words "content scene son door spend plastic clothes talk reason" (9 words)

The first address is this "13VfVDEPU4RDKPtLmQ3jhCsnrj9JwVpgkq"

If you restore from seed with these words "content scene son door spend plastic clothes talk reason damn haunt" (11 words)

The first address is this again "13VfVDEPU4RDKPtLmQ3jhCsnrj9JwVpgkq" It is the exact same wallet!



What is going on...   

[ThomasV]

yes, the seed is encoded using groups of 3 words, extra words are ignored.

(note that version 2.0 will use a hash of the seed phrase)

[wingsuit]

yes, the seed is encoded using groups of 3 words, extra words are ignored.

(note that version 2.0 will use a hash of the seed phrase)

Okay thank you, cheers for the time spent coding all this.

[ThomasV]

yes, the seed is encoded using groups of 3 words, extra words are ignored.

(note that version 2.0 will use a hash of the seed phrase)

How come it does not warn the user when entering a short seed? This significantly increases the chance of a collision.

you are right, it should warn the user.
however, the software only generates seeds with 12 words.
there can be a collision only if users invent a seed, and "restore" from it

[Abdussamad]

On a related question, will seeds that are more than 12 words (and multiples of 3) always be supported? It came up in this thread where hobbes talks about concatenating 2 wallet seeds to create a 24 word seed:

https://bitcointalk.org/index.php?topic=354261.0

[ThomasV]

On a related question, will seeds that are more than 12 words (and multiples of 3) always be supported? It came up in this thread where hobbes talks about concatenating 2 wallet seeds to create a 24 word seed:

https://bitcointalk.org/index.php?topic=354261.0

in version 2.0, the seed phrase will be hashed in order to generate the master public key.
thus, any phrase length will be supported.

However, in order to recognize seeds from version < 2, I plan to check if the number of words is 12.
so it's probably not a good idea to create 24 words seeds now.

[wingsuit]

However, in order to recognize seeds from version < 2, I plan to check if the number of words is 12.
so it's probably not a good idea to create 24 words seeds now.

What will the default seed length in 2.0 be then?

[hobbes]

On a related question, will seeds that are more than 12 words (and multiples of 3) always be supported? It came up in this thread where hobbes talks about concatenating 2 wallet seeds to create a 24 word seed:

https://bitcointalk.org/index.php?topic=354261.0

in version 2.0, the seed phrase will be hashed in order to generate the master public key.
thus, any phrase length will be supported.

However, in order to recognize seeds from version < 2, I plan to check if the number of words is 12.
so it's probably not a good idea to create 24 words seeds now.

Maybe you could allow 12 OR 24 words. 24 words allow for safe (??) and simple key splitting.

Probably there will have to be an option or some way to tell the program whether the seed is old or new...   or will the new seed have a different number of words?