Wikipedia:Reference desk/Archives/Miscellaneous/2016 February 19

= February 19 =

Why do I have to show my key and press a button?
The building where I work houses several companies, each on its different floor. Because of security reasons, to actually get to the floor of my company I have to show my magnetic key at the elevator, otherwise it won't move. Only then does my keypress for the floor get recognised.

Here's the thing. It's not enough to show just any key for the building - it has to specifically be a key for my company's floor. Everyone's key only works for the floor they are employed on, if they press their button without showing their key, the elevator goes right past the floor.

Why, then, do I have to both show my key and press the button? Shouldn't the elevator already know where I want to go? J I P &#124; Talk 16:41, 19 February 2016 (UTC)
 * Presumably there are people (like security personnel) that have a universal key. It would be rather inefficient if they had to carry a different key for each floor. That would at least explain why there need to be buttons. The elevator could still automatically choose your floor if you have a normal card though. Probably just a lazy design. - Lindert (talk) 16:52, 19 February 2016 (UTC)


 * Are there companies with multiple floors? Perhaps a person may have a key which authorizes them for two or three floors, and thus would have to pick the specific floor they wish to go to... -- Jayron 32 17:13, 19 February 2016 (UTC)


 * There's also possibly a security aspect. Assuming the keys are not identifiable to the company, then under your scheme a person finding a key would be able to go to the relevant floor. This way it is a (rudimentary) two-factor authentication system. --ColinFine (talk) 19:11, 19 February 2016 (UTC)


 * What's stopping the would-be thief of trying all the floors by brute force? There's only less than ten of them. The top two floors belong to the same company but all other companies have one floor each. J I P  &#124; Talk 19:40, 19 February 2016 (UTC)


 * If there are too many selections of unauthorized floors, it might alert the security guards to check it out. StuRat (talk) 22:30, 19 February 2016 (UTC)


 * In my building, we have the same kind of system - but our offices are on two floors. The elevator doesn't know which one I want to go to unless I tell it. So the badge isn't enough by itself.  With our elevators, the badge recognition system is made by an entirely different company than the elevator itself - and the style of the detector pad is very different from the styling of the elevator itself - suggesting that they were not developed together..  Probably, in order to be minimally intrusive to the elevator itself, all it does is to 'unlock' the buttons so you can press them yourself.  I don't get the feeling that the control unit actually talks to the elevator software at all.  That may also be a part of some regulatory system...elevators are quite highly regulated (at least here in the USA) - so it might be that messing with the fundamental operations of the machine would require expensive re-certification or something.  SteveBaker (talk) 21:54, 19 February 2016 (UTC)


 * They would need to talk to each other to some extent, perhaps only consisting of the security software saving a file listing which floors are currently authorized, and the elevator software checking that file to see if the floor selected is authorized. StuRat (talk) 22:28, 19 February 2016 (UTC)


 * I think that's more complicated than they actually are. What I strongly suspect is happening is that the panel on the elevator that contains the buttons is connected to the elevator's electronics by some kind of convenient connector (so you can remove the panel for service).  The least intrusive way to add your third-party security pad would be to unplug the buttons from the elevator electronics and plug them into the security pad instead.  Then the security pad could have a bunch of relays that allow it to disconnect the buttons from the electronics at will.  That being the case, the security pad probably has no idea what floor the elevator is on or perhaps even that it's controlling an elevator at all.  When you swipe your badge, all it has to do is to energize the allowed relays the 20 seconds or so.  Since the same pad design is used to do other things in our building - such as unlocking doors and turning on lights - I suspect that the pad basically just toggles relays on and off depending on what it sees on the card, which would allow them to be used in any number of applications.  I've seen one in a previous job that could be swiped to allow the vending machine to dispense free soda cans to employees.  (It was added after one of the buildings' cleaners discovered that the machine gave away free stuff and emptied it every night...until they were caught on a security camera struggling out of the building with about 30 cans of soda piled up on their cleaning cart.)   Our management added the pad in about 24 hours - so I suspect they just used one of the spare pads they must have lying around.  SteveBaker (talk) 23:08, 21 February 2016 (UTC)


 * In certain parts of Mexico, they don't got to show no stinkin' badges. Clarityfiend (talk) 00:51, 20 February 2016 (UTC)

Longest numbered road in UK
Does anyone know the longest numbered road in the UK (by which I mean with the highest house number?) Amisom (talk) 23:16, 19 February 2016 (UTC)
 * A quick |Google search suggests it's 2679 Stratford Road, Solihull. Dalliance (talk) 00:21, 20 February 2016 (UTC)
 * Just goes to show how house number practices vary around the world. My house number is twice that high, and I live on a short street in a subdivision.  In the U.S. many (though not all) municipalities number their addresses not strictly sequentially, but based on distance from baselines.  In Chicago, where I formerly lived, house numbers could get well into 5 digits on the far south side.  -- Jayron 32 00:59, 20 February 2016 (UTC)
 * There are also places that are kind of like counting from a baseline but not quite. I once was confused trying to find the center of a city before I realized the streets go like Street St = 200 North, Next Street = 100, Streetafterthat Street = 200 South. And the same for East and West. This makes no sense.


 * Also there's places where the street grid is only semi-regular. Up to tens of numbered streets could be skipped where there's only room for one or street numbers could repeat (like 67th Avenue, 67th Road, 67th Drive, 68st Avenue, 68st Road, 68st Drive..) and if there's one street per number they don't have to be the same distance apart. So the most significant digits of the house number have to count streets and not lots or mile fractions. They can't have only one digit besides the street because it's too easy to have at least 10 buildings on a block but the short blocks that increment the street number quickly can't have much more than 10 buildings even though their addresses have room for 99 house numbers. So non-distance based street counting address system tend to have bigger house numbers than pure house counting systems as well. House numbers go to over 27001 in New York City without using distance counting (and over 100000 in rural America with distance counting I think) Sagittarian Milky Way (talk) 03:50, 20 February 2016 (UTC)
 * The highest numbered address I have seen in rural America was 486123. The 486 has a very specific meaning, which is that it is the milepost, in this case from the southern border of Idaho.  I would expect to see equally high numbers in a state such as Tennessee from the western border of the state.  Robert McClenon (talk) 23:46, 20 February 2016 (UTC)


 * See Reference_desk/Archives/Miscellaneous/2013_November_18 for a previous discussion on this subject. In the UK, designers of modern housing developments tend to avoid long stretches of housing with the intention of creating small communities in each street. Many of our longer roads pre-date the concept of an "official" name and tended to be given a different name in each settlement that it passed through. An example is the A11 road (England) which is the main route into London from the north east and was originally built by the Romans. It starts being called Aldgate, then Aldgate High Street, then Whitechapel High Street, then Mile End Road, then Bow Road and so on; all in the first three miles from the City and one continuous roadway. I did a quick search to find the highest house number in Greater London, and 1557 London Road, Norbury appears on a couple of message boards. It's certainly very unusual to see anything higher than 400. Alansplodge (talk) 12:25, 20 February 2016 (UTC)
 * That last statistic was demonstrably wrong, as there is a 1565 London Road, Norbury. Alansplodge (talk) 12:59, 20 February 2016 (UTC)
 * Doing a virtual drive along that road in Google streetview suggests that there is a building numbered 1597 a little further up the road, the Norbury Islamic Academy claims that number...and it's the last building before a bridge over a stream. The buildings on the other side of the bridge have small numbers and the building on the opposite side of the street is also lower.  So 1597 is without doubt the highest numbered building on London Road, Norbury.  But who knows whether there aren't longer roads with more buildings out there somewhere? SteveBaker (talk) 04:18, 23 February 2016 (UTC)