Aunc.1819
net.news
utcsrgv!utzoo!decvax!duke!unc!smb
Tue Feb 9 10:20:57 1982
Maps of the World
I have a program that will produce a least-cost path from any point on
USENET to any other. Obviously, for this to work right, I need accurate
information on the connections, and the cost of each connection. My
current input file is based on Mark's USENET map; however, I *know* that
there are many more connections available. If people will mail me the
appropriate data for their nodes, I will incorporate it into the map.
*Please* send it in the format described below; also, do not include links
that will not forward mail from outside. When the program is
distributed (it will be; until then, I'll be glad to produce maps of the
world from anyone's point of view, using my most current data), you'll be
able to include your own files which list non-public paths.
Enclosed is the definition of the Usenet nodes in North Carolina, as
well as the output the program produces.
First is a definition of the UNC local net. To the pathalias program,
a local net is one with full implied addressing, and approximately
equal costs between any two nodes. The '.' character is the network
routing character; that is, a user on 'grumpy' would say 'sleepy.fred'
to send a letter via the net. If the '.' preceeded the '{', the
host-name would come last: 'fred.sleepy'. The default, of course, is
'!'. '(LOCAL)' is the cost of sending a message over this net.
The following lines set up aliases for 'unc', 'grumpy', 'sleepy', and
'happy'; normally, names like 'd' should not be used network-wide.
The Duke system is a more typical definition. Each site is listed,
along with the sites it connects to; the cost is shown in parentheses.
A network routing character may either preceed or follow any node name
in the list. Links are not bidirectional unless they are explicitly
coded as such.
#
# Define the UNC net
#
UNC = {unc, grumpy, sleepy, happy}.(LOCAL)
unc = dopey, d, dvax
grumpy = g, gvax
sleepy = s, pdp
happy = h
#
# Now Duke
#
duke phs(DIRECT-5), dukgeri(DIRECT-5), duke34(DIRECT-5)
phs duke(DIRECT)
dukgeri duke(DIRECT)
duke34 duke(DIRECT)
#
# and MCNET
#
mcnc simon(DIRECT), unc(DIRECT), duke(DIRECT), web40(DIRECT+LOW),
wolfvax, ncat(DIRECT)
mcnc = alvin
simon mcnc(DIRECT)
unc mcnc(DIRECT)
duke mcnc(DIRECT)
wolfvax mcnc
ncat mcnc(DIRECT)
#
# UNC - Charlotte
#
web40 mcnc(DIRECT-5), twin40(DIRECT)
twin40 web40(DIRECT)
#
# Triangle area
#
unc duke(HOURLY), tucc(DIALED)
duke unc(DIRECT), tucc(DIRECT)
tucc unc(HOURLY-25), duke
------------
This map is from unc's point of view. The output shows the cost, the
site name, and the path to reach the site; a '%s' indicates where the
userid belongs. Network routing characters other than '!' except at an
end of the string are likely to cause trouble, because there's no
guarantee how the intermediate node will parse them. That is, some
site along the way to say, Berkeley, might interpret a Berknet ':' in
its own way, rather than giving the '!' higher precedence.
0 dopey %s
0 unc %s
0 d %s
0 UNC %s
0 dvax %s
10 happy happy.%s
10 sleepy sleepy.%s
10 pdp sleepy.%s
10 h happy.%s
10 s sleepy.%s
10 grumpy grumpy.%s
10 gvax grumpy.%s
10 g grumpy.%s
200 mcnc mcnc!%s
200 alvin mcnc!%s
300 tucc tucc!%s
400 ncat mcnc!ncat!%s
400 duke mcnc!duke!%s
400 simon mcnc!simon!%s
405 web40 mcnc!web40!%s
595 duke34 mcnc!duke!duke34!%s
595 dukgeri mcnc!duke!dukgeri!%s
595 phs mcnc!duke!phs!%s
605 twin40 mcnc!web40!twin40!%s
4200 wolfvax mcnc!wolfvax!%s
------------
Below are the numeric cost values. The primary consideration is the
frequency and reliability of the connection; my assumption is that baud
rate is a minor variable compared to how long it will take to start the
mail transfer. Costs may be combined using parentheses, '+', '-', '*',
and '/'.
LOCAL 10 High-speed local net
ARPA 31 ARPA net connection
DEDICATED 95 BerkNet, or other line dedicated to file transfer
DIRECT 200 Hard-wired connection used for 'cu' and 'uucp'
DEMAND 300 Node called on demand, i.e., whenever there's traffic
DIAL 300
DIALED 300
HOURLY 500 Connection made hourly (typically, via a poll)
--> DEFAULT 2000
POLLED 5000 Polled daily
DAILY 5000
WEEKLY 30000 Polled weekly
HIGH -5 Baud rate or line quality modifiers (additive)
LOW 5
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The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996
Bruce Jones, Henry Spencer, David Wiseman.