Clipper for luggage
chessler at usa.net
Sun Nov 16 18:45:08 EST 2003
At 03:00 PM 11/16/03, peter gutmann wrote:
>Bill Frantz <frantz at pwpconsult.com> writes:
> >>I usually travel with zipper closed duffel bags. I fasten the zipper
> >>with a screw link. Anyone can unscrew the link and get into the bag,
> >but it
> >>does effectively keep the zipper closed in transit. I suppose it also
> >>provides some level of security because someone wanting to do a quick
> >>from luggage will probably pick a less-secured piece.
>Whentrue locks are banned, that's actually a rather good protection
>mechanism, constituting a type of hashcash for luggage. Someone who's
>looking for targets of opportunity and has a choice between a
>Clipper-locked container they can get into almost unnoticed in 5 seconds
>or something where it'll take a minute or two of obvious fiddling will
>presumably go for the Clipper-lock. Just don't go overboard with those
>custom foot-long screw machined "locks".
TSA had been recommending electricians cable ties made of nylon. The 4" (10
cm) or 8" (20 cm) sizes work well in most zipper-type locks. They can't
easily be removed without cutting them. I had "improved" the ties by using
colored ones (available at most electrical supply houses and better
hardware stores), so that there would be clear evidence of entry. For
further security I dropped a bit of colored sealing wax on each cable tie.
On a longer trip I have to carry spare cable ties. I made sure not to have
spares of the color I used on each leg. I also tried to carry the spare
cable ties and spare sealing wax (several colors) in my carry-on (or my
pockets). These can easily be cut with fingernail clippers, which are now
"legal" to carry, and which can also be carried in an unlocked pocket on
the checked bag.
For some years, numbered one-use nylon or plastic ties have been available
in luggage supply stores. These also have to be cut or broken to open the
suitcase, and they cannot readily be replaced because the serial numbers
None of these totally prevent theft, but any lock that can fit through most
zippers can easily be cut with a short 12-inch bolt cutter (30 cm long),
that can be bought for $10 at Sears or most hardware stores, and that will
fit in the pockets of most work-clothing. (Indeed, it can probably be cut
with an 8" (20 cm long) diagonal cutting pliers (or electricians pliers).)
Given the lax security in the back areas of the airports, it's easy enough
for the baggage handlers to have cutting instruments. But, if the object is
to be able to tell immediately that the suitcase has been opened, and so
file a claim, they will work.
Indeed, if all you have to do is slow down a thief, then a "twist tie" or
the plastic seal from a garbage bag can be used to seal the lock.
Hard-sided luggage is more difficult to lock in this way. However, the
plastic cable ties are available in lengths up to about 48" (120 cm). These
can be passed around the bag and tightened (if necessary, two or more can
be linked together). Since these are not available in colors, and are too
big to be convenient in carry-ons (and might invite queries since they are
the same things that police use as handcuffs), the lock portion should be
sealed with sealing wax.
The Cryptography Mailing List
Unsubscribe by sending "unsubscribe cryptography" to majordomo at metzdowd.com
More information about the cryptography