rayan@ai.toronto.edu (Rayan Zachariassen) (01/04/89)
Many of the forms I get sent are out-of-spec wrt details of their
syntax. I make an effort to correct such problems before the entry
goes into the map, but I keep doing this over and over with the same
entries. Obviously many of you are stashing your entry away somewhere
and never look at what actually makes it into the map. Even worse, you
give your entry to friends and foes who then start sending me forms I
have to correct. Because there are so many of them, it has been easier
to just edit the forms every time I get them instead of sending back
individual complaints. The stuff I waded through for the posting in
early December was very bad, about 60% of entries had errors. This
month's posting (which went to rutgers today) had maybe 30% errors in
the submitted forms. I'm sure some of you aren't aware you don't have
proper forms, so here's a plea:
When the next map posting comes out, go refresh the copy of Your
map entry that you have squirrelled away somewhere with whatever
you find in the map. Then use that as a base.
It would be quite helpful if everyone did this, so please take the time.
There are also some creative people out there that like to give better
information in a non-standard way... please remember that the maps are
supposed to be parsed by programs, including the #<letter> lines! This
means your creativity is better expressed in real comment lines instead of
the ones that have predefined syntax and semantics.
Here are some quick guidelines for new sites:
- copy another site's map entry FROM THE MAP, not from what they send you.
- UUCP host names may not (by fiat) contain uppercase letters or underscores.
It is recommended they start with an alphabetic and continue with
alphanumerics or dashes and don't end with a dash.
- get in the habit of checking your map at regular intervals. Whether or not
there have been any changes, you should send in a new one every 6 months,
and always remember to update the timestamp (the #W line) with the output
of the date command.
- if you don't know your latitude/longitude, try interpolating based on
nearby UUCP sites, or ask your local library, airport, or city hall.
(I have heard interesting stories of people's reactions when asked
"Where are you?" or "Where am I?", so don't get discouraged!)
- do not use @'s *anywhere* in the link data, this is an especially popular
thing to do for internal LANs but is outlawed. The objective is to
end up with all-! unambiguous routes.
- think hard before you register internal hosts in your organization. If
you have any, your site is a good candidate for needing a domain name.
The map is Very Large and doing our bit to reduce it is important.
- always send map *updates* to utai!path. Like it says in the first few
lines of each map file, sending to rutgers!uucpmap is totally useless for
updates since Mel Pleasant just forwards it to utai!path. Send it to
utai!path to begin with. Also, please don't send map-related stuff to
me personally, but use the utai!path address. Map maintenance is done
out of an account at CSRI which serves to collect all the information.
If you mail to utai!path, I will see it in my mailbox too. If you mail
to me, I have to forward it to utai!path anyway.
You may be interested in some numbers from the latest map crunching:
There are approx 370 registered UUCP sites in Canada, approx 6330 in the
world. There are 16390 known ``names'' in the UUCP map (this includes domain
names, aliases, and ghost sites -- sites that aren't registered), and about
37.5k links.
There are 58 registered subdomains of CA, 12 of which where handled through
the UUCP liaison (me). There is 1 .COM and 4 .EDU subdomains in Canada
(that I know of) and several more subsidiaries of .COM's based elsewhere.
The UofToronto LAN map database is about 1Megabyte of text, approx
4Meg of DBM files (about half are holes). If this seems a bit larger
than yours, it might be because all our outgoing links are referred
to by long.domain.names.
Its a big BIG world.
Happy New Year!
rayanchk@dretor.dciem.dnd.ca (C. Harald Koch) (01/05/89)
In article <89Jan3.211712est.38118@neat.ai.toronto.edu> rayan@ai.toronto.edu (Rayan Zachariassen) writes: [ lots of stuff ] >- if you don't know your latitude/longitude, try interpolating based on > nearby UUCP sites, or ask your local library, airport, or city hall. > (I have heard interesting stories of people's reactions when asked > "Where are you?" or "Where am I?", so don't get discouraged!) Other solutions: Obtain a GPS receiver and ask it where you are while standing next to your computer. (GPS = Global Positioning System, a US military satellite system for accurate positioning data.) Here is a way to find a rough approximation: Find the latitude/longitude of a known reference point that you can locate on a local map. For Toronto, there is a post at the northeast corner of the Sanford Fleming building at UofT. This is close enough to the intersection of King's College Rd. and King's College Circle for measuring purposes. (Can someone at UofT run outside and find the coordinates of this post for me?) Measure the (x,y) distance from the known reference point to your location along an East-West line and a North-South line. (i.e. The CDF computer room is about 100m south and perhaps 70m west of this reference point. Using simple trig, and the fact that the average radius of the Earth is 6,371,225 meters, we find that the circumference of the earth is 40,031,587 meters, and thus there are rougly 30 meters to each second of latitude (the North-South measurement). Given the angle of latitude of your location, you can find the ratio of distance to seconds of latitude as: 2 * pi * 6371225 * cos(latitude) -------------------------------- 1296000 (= 360 * 60 * 60, the circumference in seconds) This gives a ratio in meters/second (boy, are we moving fast now!) Around here, this is (very roughly!!) 22 meters/second. Now, convert the distances you measured into offsets from the known location to your location (in seconds). Add these to the coordinates of the known location. Tahdah! Instant reasonably accurate position information for your site. If you want to get fancy, you can find the location the center of your building, say, and then give slightly corrected offsets for all the machines on your building. But this, of course, is plain silly. :-) If any mathematicians feel like jumping all over my reasoning here, go right ahead. I never took R&F. NOTE: This method is inaccurate for long distances!!!! This is due to the errors introduced when you project the surface of a sphere onto a flat map. I have seen maps that have aspect ratio corrections for various areas (We have one on the wall outside the library here at DCIEM), but these are rare (and expensive...). -- C. Harald Koch NTT Systems, Inc., Toronto, Ontario chk@zorac.dciem.dnd.ca, chk@gpu.utcs.toronto.edu, chk@chkent.UUCP "I give you my phone number. If you worry, call me. I'll make you happy."
bar@dptcdc.datapoint.com (Brian Ruptash) (01/05/89)
There's a "better way", as I found out today from a surveyor
wandering about our office tower.
You may have noticed those little brass plates with triangles etched
in them, imbedded around street corners in Toronto. They are called
control monuments, and are used as reference points for surveyors.
Get the number off of the one closest to your location, and call
up the Metro Central Mapping Agency (392-2516). Ask for a Metro
benchmark for your location (give them an intersection), and give
them the control monument number. They'll respond with a set of
north/east coordinates in the Ontario 3 degree zone coordinate
system, which is a pair of distances in metres from some reference
point (from the numbers I got, I'd guess the southern most tip of
Ontario).
They can then run these coordinates through a program to convert
to latitude and longituide. The result is the latitude/longitude
of the control monument to the nearest 1/100th of a second.
If you then want a more accurate position (like to the centre of
the CPU in your processor), you can use Harald's previously posted
formulae...
--
Brian Ruptash | Internet: bar@toronto.datapoint.com
Principal Architect | UUCP: {uunet, utzoo}!dptcdc!bar
Datapoint Corporation | Phone: (416) 222-8005bdb@becker.UUCP (Bruce Becker) (01/06/89)
In article <1340@dretor.dciem.dnd.ca> chk@dretor.dciem.dnd.ca (C. Harald Koch) writes: >In article <89Jan3.211712est.38118@neat.ai.toronto.edu> rayan@ai.toronto.edu (Rayan Zachariassen) writes: >[ lots of stuff ] >>- if you don't know your latitude/longitude, try interpolating based on >> nearby UUCP sites, or ask your local library, airport, or city hall. >> (I have heard interesting stories of people's reactions when asked >> "Where are you?" or "Where am I?", so don't get discouraged!) > >Other solutions: Obtain a GPS receiver and ask it where you are while standing >next to your computer. (GPS = Global Positioning System, a US military >satellite system for accurate positioning data.) > >Here is a way to find a rough approximation: > [ explanation deleted ] In the city of Toronto, & likely other places as well, the Survey Department has installed brass markers, mostly in the sidewalks, which indicate known survey reference points, and which if I'm not mistaken are marked with the latitude & longitude on them. Harald's useful method outght to work for a few kilometers without much problem - certainly close enough for pathalias map usage. So once you have an accurate known point, even a Perly's map might be sufficient... >C. Harald Koch NTT Systems, Inc., Toronto, Ontario >chk@zorac.dciem.dnd.ca, chk@gpu.utcs.toronto.edu, chk@chkent.UUCP >"I give you my phone number. If you worry, call me. I'll make you happy." Cheers, -- _ _/\ Bruce Becker Toronto, Ont. \`o O| Internet: bdb@becker.UUCP, bruce@gpu.utcs.toronto.edu \(")/ BitNet: BECKER@HUMBER.BITNET ---mm-U-mm--- "The OSF is suffering from Penix envy" - Rocky Raccoon
chk@dretor.dciem.dnd.ca (C. Harald Koch) (01/06/89)
In article <1340@dretor.dciem.dnd.ca> chk@dretor.dciem.dnd.ca (C. Harald Koch) writes:
[Lots of stuff about how to calculate your position]
Mark Brader (msb@sq) just pointed out to me that all of this stuff is in the
README file that comes with the map distribution. Furthur, he wrote it while
working for NTT Systems a few years back. (Check the Organization line if
you don't understand...)
Teach me to read the bloody documentation.
--
C. Harald Koch NTT Systems, Inc., Toronto, Ontario
chk@zorac.dciem.dnd.ca, chk@gpu.utcs.toronto.edu, chk@chkent.UUCP
"I give you my phone number. If you worry, call me. I'll make you happy."