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How domains became backwards

david.newgas.net

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Re: How domains became backwards

#11

Post by lutusp »

andrewcooke wrote: post #6
DLWormwood wrote: post #5

Earlier quoted context omitted.

That language is math . Which, due to historical accident, was inspired by Arabic writing, rather than the Latin variety.

that sounds interesting, but i'm having a hard time getting my head round it. can you give an example where math is right to left? [edit oh, numbers! thanks! i was thinking about algebra.]

Sure -- Scheme:

Link: http://weber.marblefalls.txed.net/mfhs/academics/electives/c...

Example:

    (+ 5 (* 10 x))
Which more or less means 5 + 10 * x in everyday notation.

Compare to Reverse Polish Notation (used in Hewlett-Packard calculators and elsewhere), which would express the above as:

    10 x * 5 +

Re: How domains became backwards

#12

Post by T-hawk »

andrewcooke wrote: post #6
DLWormwood wrote: post #5

Earlier quoted context omitted.

That language is math . Which, due to historical accident, was inspired by Arabic writing, rather than the Latin variety.

that sounds interesting, but i'm having a hard time getting my head round it. can you give an example where math is right to left? [edit oh, numbers! thanks! i was thinking about algebra.]

Numeric notation is built right to left. To count up from 1 to 9 uses single digits, of course. Then to go from 9 to 10, the ones place increments and rolls over, and we add the new tens digit on the left, not the right.

Re: How domains became backwards

#13

Post by _mhp_ »

jbert wrote: post #9

The UK "Grey Book" email system ( http://en.wikipedia.org/wiki/Coloured_Book_protocols ) used email addresses the other way around (in the same timeframe that the UK was using a stack over X.25 as their internetworking protocol). For example, a user at Imperial College (IC) would have been: user@uk.ac.ic, rather than user@ic.ac.uk as they might today. Email gateways existed to convert between the different systems, b…

I wondered why the article didn't mention JANet-style addressing, or UUCP-style bang-paths, both of which lead to more specific elements on the right.

With the rise of NAT-traversal technologies, I find it a little disappointing that bang-path addressing hasn't been rediscovered and used with TURN.

Re: How domains became backwards

#14

Post by codev »

JANET (the UK university network) had a NRS (Name Registration Service - similar to DNS) that worked from least-to-most specific. So Cambridge was uk.ac.cam instead of today's cam.ac.uk. There were gateways to talk to email servers on ARPANET and reverse the ordering - there's more on it here:

http://www.uknof.com/uknof7/Reid-History.pdf

Re: How domains became backwards

#15

Post by advisedwang »

opminion wrote: post #3

Funny to think that if Twitter handles were fragments of email addresses they would be backwards: com.twitter@holysee --- By the way, this must be a mistake: This is a clearly a byproduct of the right-to-left language of the designers of these systems

Thanks, fixed

Re: How domains became backwards

#16

Post by bnegreve »

T-hawk wrote: post #12
andrewcooke wrote: post #6

Earlier quoted context omitted.

that sounds interesting, but i'm having a hard time getting my head round it. can you give an example where math is right to left? [edit oh, numbers! thanks! i was thinking about algebra.]

Numeric notation is built right to left. To count up from 1 to 9 uses single digits, of course. Then to go from 9 to 10, the ones place increments and rolls over, and we add the new tens digit on the left, not the right.

Not sure, the numeric notation is little endian wheras DNSs are big endian.

Re: How domains became backwards

#18

Post by greenyoda »

syncsynchalt wrote: post #7
polymathist wrote: post #2

Interesting. Now I wonder why Java decided to go the other way with a reversed domain name for packages. E.g., com.company-name.package-name

In the initial implementation package names were literally mapped to a path with the equivalent of subst(".", "/"). So in that sense the java package names are based on the hierarchy of a filesystem.

Also, the method name goes to the right of the class name, so the only reasonable way to have a hierarchical name that reads in a single direction is to put the most general qualifier on the left and the most specific on the right:

com.mydomain.mypackage.MyClass.staticMethod()

Re: How domains became backwards

#19

Post by samatman »

spindritf wrote: post #17

Group hierarchies on USENET were from least to most specific, for example sci.math.num-analysis.

There are good reasons for both of these choices.

USENET was a taxonomy, at least in principle, although like any taxonomy of thought you ran into cases like sci.foo.bar and alt.foo.bar fairly often. A taxonomy should be read from general to specific.

Email addresses are addresses. The metaphor is a geography, which goes from the specific to the general.

Then we have URLS, which go from the specific to the general, hit a slash, reverse direction, and then explode into a bunch of hacked-on features.

Re: How domains became backwards

#20

Post by taproot »

andrewcooke wrote: post #6
DLWormwood wrote: post #5

Earlier quoted context omitted.

That language is math . Which, due to historical accident, was inspired by Arabic writing, rather than the Latin variety.

that sounds interesting, but i'm having a hard time getting my head round it. can you give an example where math is right to left? [edit oh, numbers! thanks! i was thinking about algebra.]

He meant left to right. It was a [fixed]mistake in the article.
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