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bonanova

Locks and keys

Question

You want to send a valuable object to a friend.

You have a box to contain the object.

The box has a locking ring which is more than large enough to have a lock attached.

You and your friend have several locks with keys.

But your friend does not have the key to any lock that you have, and vice versa.

How do you do it?

Note that you cannot send a key in an unlocked box, since it might be copied.

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that's what I had in mind as well

Me too, Or you can handle this like a bridge crossing riddle. Send the locked box with your lock, friend sends it back with your lock and his lock, take off your lock and send it back and he can take off his lock.

Edited by Jordanmax

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You want to send a valuable object to a friend.

You have a box to contain the object.

The box has a locking ring which is more than large enough to have a lock attached.

You and your friend have several locks with keys.

But your friend does not have the key to any lock that you have, and vice versa.

How do you do it?

Note that you cannot send a key in an unlocked box, since it might be copied.

You lock the box send it to him... he adds a lock to the box and sends it back. You remove your lock and send it back to him he unlocks it.

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Which reminds me of the old quote:

All of you who believe in telekenesis please raise my hand.

/raises hand B))

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you have the friend send you a lock and key that they can keep a key to as well. Then you can put the item in a box, lock it with the lock the friend sent. The friend will receive the locked box which he/she now has the key to and can open.

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Send the box with a lock on it. Ask your friend to put another lock over it and send it back to you.

Now you remove your lock and send it back to your friend. Now he has the key for the other lock

:-)

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You lock the box send it to him... he adds a lock to the box and sends it back. You remove your lock and send it back to him he unlocks it.

I see this is a pretty common answer. As a programmer, I think this is best. It's a an excellent method of data encryption, espcially used for sending encryption keys.

Say I want to open a secure channel of communication with you, so we need to encrypt our data. In order for me to send you the key with which to decrypt the data, I would encrypt the key with my own private key. You would then encrypt the encrypted key with your own private key. I would then decrypt the twice-encrypted key with my private key and send it back to you. All you'd have to do is decrypt the encrypted key with your private key and we'd have a shared key!

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how about...

1. You send him the box.

2. He sends you back his lock in the box.

3. You lock the box with the valuable object inside and send it back to him.

4. He opens the box.

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instead of sending a valuable object to the friend, send the friend a letter telling the friend where to meet so that you give it personally

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You want to send a valuable object to a friend.

You have a box to contain the object.

The box has a locking ring which is more than large enough to have a lock attached.

You and your friend have several locks with keys.

But your friend does not have the key to any lock that you have, and vice versa.

How do you do it?

Note that you cannot send a key in an unlocked box, since it might be copied.

You put a lock and send it to your friend.

Your ffiend puts another lock(for which he has the key) and send the box back to you.

You remove your lock from the box and send it again to your friend.

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k, people, there is no need to put two locks on the box! All you need to do is send him an empty box,

he throws a lock in the box, without locking it, and send it back to you, you put your object in and lock

the box and send it back to him. There you go!

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How about you just buy a combination lock and give him a call once the package has arrived.

I'm guessing that you want a bridge style answer though.

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I'd have my friend send me one of their locks. They would send it open and keep the key. This way, in a real life situation, you don't have to worry about geting your lock back.

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Have your friend send you one of his/her open, unlocked locks (he/she keeps the key); you put the valuable in the box, lock it with your friend's lock and send it. OR--lock the box with your lock and send the key separately. Either way you have two shipments; however, the second one means you lose one of your own locks and keys.

You want to send a valuable object to a friend.

You have a box to contain the object.

The box has a locking ring which is more than large enough to have a lock attached.

You and your friend have several locks with keys.

But your friend does not have the key to any lock that you have, and vice versa.

How do you do it?

Note that you cannot send a key in an unlocked box, since it might be copied.

Edited by Lizzie

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i think that if it is possible to make a new lock with 2 keys then do it and meet the friend give them 1 key then send the box

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You want to send a valuable object to a friend.

You have a box to contain the object.

The box has a locking ring which is more than large enough to have a lock attached.

You and your friend have several locks with keys.

But your friend does not have the key to any lock that you have, and vice versa.

How do you do it?

Note that you cannot send a key in an unlocked box, since it might be copied.

You put the package in the box, snap a lock on and send it to your friend.

When your friend receives the box, he puts a lock of his own on it, alongside the original lock and sends it back to you.

When you receive the package back you remove the first lock (your) and send the now single locked package back to your friend. Your friend can then open his lock and have the package.

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After taking a college course in Networking which had some encryption work, this answer is pretty easy. There are a couple ways to do this:

1) User A sends his unlocked lock, keeping his key, to User B. User B sends the data in the box, locking it with the lock sent by User A.

2) User A sends the data to User B in a box locked with his lock (lock A). User B receives the box and applies his lock as well (the box now has locks A and B), sending the box back to User A. User A unlocks and removes his lock; he now has the data he wants to send locked with only lock B to send back.

In this situation, it seems scenario 1 makes the most sense, but scenario 2 can make more sense in some cases (usually in cases of data encryption with passwords and codes).

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Have your friend send you one of his locks, unlocked. (The fact pattern doesn't requries that it be in a locked box.) Lock your box with his lock, then send him the locked box. He then opens the lock with his key.

I think that this is the simplest answer

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1.Does your friend need to be 100 % sure you send him the box and not someone else ?

2.Do you need to be 100 % sure your friend is the only one who can open the box ?

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1.Does your friend need to be 100 % sure you send him the box and not someone else ?

2.Do you need to be 100 % sure your friend is the only one who can open the box ?

3. are all of my keys private ?

4. are all of my locks private ?

(is it me or can't we edit posts ?)

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I don't get it why the box is so important...it is the stuff that you are sending which is important. So send you stuff with your lock, and your friend can either cut the lock or the ring holding the lock to get the stuff out...simple!! Next time use another lock!

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Which reminds me of the old quote:

All of you who believe in telekenesis please raise my hand.

if you find yourself raising your hand for no reason throughout the day..it wasn't me.... :whistle:

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