taylor@glasgow.glasgow.UUCP (Jem Taylor) (09/12/86)
The following is a message posted to the mailgroup DL in the UK ... the
problem of ambiguity between least and most significant name components
is of interest to all those who have to cope with both BigEndFirst and
SmallEndFirst; Have Internet and Arpanet people considered this problem
when naming their hosts ?
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In view of the recent debate [ on a DL in the UK, and not on this board ]
about the wisdom (or otherwise) of naming a system
as uk.......com , which introduces Little/Big-Endian ambiguity, I have collected
together the names of all the top-level domains of which I am aware. Since it
is desirable to avoid using any of the names in the list below as the
final [ that is, in UK order, the LEAST SIGNIFICANT ]
component (or indeed any component) of a name, I am circulating this list and
would like to hear of any additions.
I would like to suggest that a new constraint be placed on the
NRS [ the Name Registration Scheme - the UK master nameserver database ],
to the effect that top-level names may not be used as lower-level
(especially final) components of new registrations.
The reasons for this constraint are two-fold:
(1) Not permitting a top-level domain name to occur as the final sub-domain
name eliminates Little/Big Ambiguity.
(2) Not permitting a top-level domain name to occur as an intermediate sub-
domain name allows users to input partially resolved domain names of the
form mysite.mydept instead of the fully-qualified domain name
top.sub.sub1.mysit.mydept without thereby introducing Little/Big Ambiguity.
Examples of the Ambiguity:
(1) uk......com - or is that com.....uk ?
(2) uk.ac.edu.vax - typed as edu.vax from uk.ac.edu.prime - is that vax.edu ?
Although many sites stick firmly to one ordering or the other (JANET or ARPA),
some sites will always have to try to understand both orders, in order to
relay between incompatible domains or to allow users to type the addresses
which their correspondants have told them in the other order.
-Jem Taylor.
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JANET: taylor@uk.ac.glasgow.cs
UseNet: mcvax!ukc!cs.glasgow.ac.uk!taylor
ARPANet: taylor%cs.glasgow.ac.uk@{ucl-cs.arpa,cs.ucl.ac.uk}
Phone: +44 (0)41 339-8855 extn. 6054
Mail: J.A.Taylor, Computer Science, 17 Lilybank Gardens, GB-GLASGOW G12 8QQ
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List of top domains (and relays):
EAN domains reachable from UCL.
uk - United Kingdom
au - University of Melbourne, Australia
cdn - CDNnet, Canada
cern - European Organization for Nuclear Research, Geneva
chunet - Swiss University Network, Switzerland
dfn - Deutsche Forshungsnetz, West Germany
hasler - Telecommunications Equipment Manufacturer, Switzerland
iris - Spain
irl - Ireland
osiride - Italy
sunet - Swedish University Network, Sweden
surfnet - Netherlands
uninett - Norwegian University Network, Norway
[From UCL.CS:<DOC>ean.sites, July 25, 1986]
Unix system well-known domains (from Sendmail/UK-1.4/chn/Examples.a)
Domain Relay
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uucp ukc.ac.uk
oz ukc.ac.uk
csnet relay.cs.net (A.K.A csnet-relay.arpa, csnet-relay)
bitnet wiscvm.wisc.edu
mailnet multics.mit.edu
dec decwrl.dec.com
NRS top level domains (from NRS:t.central):
CERN
UK
DESY
Domain Gateway Context(s)
ARPA UK.AC.UCL.CS MAIL-NIFTP
MIL UK.AC.UCL.CS MAIL-NIFTP
GOV UK.AC.UCL.CS MAIL-NIFTP
EDU UK.AC.UCL.CS MAIL-NIFTP
COM UK.AC.UCL.CS MAIL-NIFTP
ORG UK.AC.UCL.CS MAIL-NIFTP
US UK.AC.UCL.CS MAIL-NIFTP
EARN UK.AC.RUTHERFORD.EARN MAIL-NIFTP
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JANET: taylor@uk.ac.glasgow.cs
UseNet: mcvax!ukc!cs.glasgow.ac.uk!taylor
ARPANet: taylor%cs.glasgow.ac.uk@{ucl-cs.arpa,cs.ucl.ac.uk}
Phone: +44 (0)41 339-8855 extn. 6054
Mail: J.A.Taylor, Computer Science, 17 Lilybank Gardens, GB-GLASGOW G12 8QQ
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