In fact, the replies generated by the e-mail recipients can even go to
the remote-printing recipients.
2.4: How much of the world is accessible via this experiment?
The official kick-off of the experiment was 16 July 1993. At that time,
service was operational for:
- Canberra, Australia (+61-62)
- Washington, DC (+1-202)
- most of Silicon Valley (+1-408, +1-415, +1-510)
- parts of Riverside, California (+1-818, +1-909)
- the University of Michigan (+1-313)
Since then, cells have been set up in the following countries:
- Denmark
- Finland
- Japan
- Sweden
- England
- Taiwan
- Canada
- Croatia
- Portugal
- Italy
- New Zealand
- Korea
- Hong Kong
Enterprises, such as companies, universities, and government R&D
centers, have also come on-line. The basic idea is that each
participating site registers a "cell" indicating the portion of the
international telephone number space that they are willing to provide
access to. A cell can be a continent, a campus, a building, or a
single phone number.
2.5: "Cells"?
Well, we call them cells. The idea is that there are really four kinds
of participating sites:
- neighborhood sites
- regional sites
- enterprise sites
- personal sites
A neighborhood site is run by someone who provides access to any facsimile
machine in its "local calling area". The idea being that metered access
to this area is fairly inexpensive, and the site is willing to provide
access as a part of their community spirit. Access to Silicon Valley was
provided by several neighborhood sites before it was scaled back recently.
The interesting thing to note is that neighborhood sites may choose to
shrink or expand their cell, depending on factors such as demand and cost.
A regional site is basically just a large neighborhood site, usually
providing access to an entire country or a large part of a country,
such as an area code. The continent of Australia was an example of a
regional site, although the initial coverage has been recently scaled
back to certain localities only.
An enterprise site is run by a company that provides access solely to
its own facsimile machines. They register exactly those telephone
prefixes which apply to their enterprise. The University of Michigan
is an example of this. Of course, a geographically-disperse enterprise
such as a multi-national company could also do this.
A personal site is run by someone who provides access to exactly one
facsimile machine, usually one that resides on their desktop. In this
case, when the remote printer server gets the message, it will just
deliver it to the owner of the desktop -- via e-mail.
Note that there can be overlapping remote printer servers for a given
area. A personal site, for example, might be in the area served by a
neighborhood site. Since the Internet domain name system always favors
the longest match, the smaller site gets precedence for its own traffic
2.6: How can I find out if there is access to a particular number?
Assuming you are on a UNIX machine:
If fax number is 1-301-555-1212, you can either do
% nslookup -query=MX 2.1.2.1.5.5.5.1.0.3.1.tpc.int
or
% nslookup -query=MX 13015551212.iddd.tpc.int
As long as the result is not sinkhole.tpc.int, the fax number
should be under the coverage. The name after the exchange should be
the fax server machine.
contributor - Frank Chen
** Users of Mac, or PC Operating systems may have similar DNS tools - DPN **
2.7: Suppose I want to send images instead of text?
Use MIME. MIME is the Internet-standards track technology for
multi-media messaging. Remote printer servers support, at a minimum,
the following MIME content types:
- text/plain
- message/rfc822
- application/postscript
- image/tiff
- multipart
So, you might send something like the following:
To: remote-printer.Arlington_Hewes/Room_403@0.1.5.2.8.6.9.5.1.4.1.tpc.int
MIME-Version: 1.0
Content-Type: application/postscript
%!
...
2.8: Suppose I want a lot of information on the cover sheet?
You want a lot of things don't you? A MIME content-type has been
defined for this. It's called application/remote-printing. Here's an
example:
Content-Type: application/remote-printing
Recipient: Darren Nickerson
Organization: University of Oxford
Department: New Chemistry Lab
Telephone: +44 1865 275975
Facsimile: +44 1865 271503
Email: darren.nickerson@balliol.oxford.ac.uk
Originator: Mr. Arlington Hewes
Organization: The Phone Company - International
Department: Administration
Telephone: +44 1234 123456
Facsimile: +44 1234 123457
Email: tpcadmin@info.tpc.int
Any text appearing here would go on the cover-sheet.
To use this mechanism, the top-level content in your message must be
multipart/mixed, and the very first content in that must be
application/remote-printing. Also, if you use this, then the left-hand
part of the recipient's address should just be "remote-printer".
2.9: Come on, you must have developed an easier address format!
Okay, you got us. . .
As soon as it became clear that the original addressing scheme of reversing
the number and separating it by periods was going to be found overly
cumbersome by many, we devised a new scheme which implements a DNS hack
developed by Mark Turner. Now instead of sending to:
remote-printer.any_name@9.8.7.6.5.4.3.2.0.9.1.tpc.int
you can send it to:
remote-printer.any_name@19023456789.iddd.tpc.int
Easy!
-DPN
2.9: Is there software to help me compose messages like this
Yes. See the section below on "Is there software available?".
3.1: Suppose I want to operate a remote printer server?
You need four things:
- a computer on the Internet (UUCP/polling's OK too)
- a fax modem and phone line
- fax spooling software
- "glue" software to pull it all together
You also need to agree to operate the cell in a fashion consistent with
the policies associated with the tpc.int subdomain.
3.2: Is there a document describing the technical details?
Yes. See RFC 1486, "An Experiment in Remote Printing". It's available
at the usual RFC repositories. In the future, there will probably be
several documents, including one on policy.
3.3.1: Who sets policy?
The tpc.int subdomain is structured as a cooperative of the remote printer
servers around the world. Policy for the subdomain is made in the
time-honored tradition of hoping that things will run well enough on their
own. In cases where additional guidance is necessary, a Board of
Arbitration and Conciliation considers situations brought to it by the
members and issues written opinions.
Initially policy was set by the two people who started the experiment,
Carl Malamud of the Internet Multicasting Service, a non-profit
organization, and Marshall Rose of Dover Beach Consulting, Inc. (Rose
spends half of his time on openly available projects, of which this is
one.) Now however, the task has fallen on the shoulders of Darren
Nickerson, a PhD student in Oxford, England.
3.3.2: "What is this policy?
Ultimately, it's all about maintaining basic principles for the
subdomain such as: functionality, fairness, cost recovery, performance,
efficiency, security, and legality.
3.3.3: What did Malamud and Rose get out of this?
An indictment by a federal grand jury. Just kidding. Ha, ha. They were
doing research on how to integrate special-purpose devices like G3
facsimile printers into the fabric of a general-purpose infrastructure
like the global Internet computer network. Neither Malamud nor Rose
profited from the project, though they sincerely hoped that operators in the
tpc.int subdomain were able to recoup their costs, save consumers money,
and maybe even make a healthy profit.
3.3.4: What does Nickerson hope to get out of this?
Well, gee. . . he's not sure. His interest was piqued by the possibility
of subverting large telco corporations, and after setting up his own cell
in Oxford, he decided to take a larger role in the development of the
tpc.int subdomain. Let's see what the kid can do.
3.3.4: Is there any guarantee that my fax will get delivered?
No. For now, there's one simple rule:
It is perfectly acceptable to deny access on the basis of originator
identity, but it is not acceptable to deny access on the basis of
recipient identity
The reason for this is simple: if a site finds that some originator is
acting in an abusive manner, then the site can deny access. But, when
a site registers a cell, it agrees to provide access to every telephone
number in that cell. Of course, it can always register a smaller
cell.
3.3.5: What about privacy?
There are strict rules as to the kind of auditing information which a
remote printer server may keep. Basically, this information is
necessary for debugging purposes, e.g., if you send a message and don't
get a completion or failure acknowledgement later on, the site
providing access may need to check into it. Also, there are strict
rules guaranteeing that the contents of a fax are secure and will not
be monitored by the remote printer server operators. Having said this,
it's only as secure as you consider e-mail to be ;)
3.4: "Who can I contact for administrative questions?
That would be Mr. Arlington Hewes (tpcadmin@info.tpc.int). Mr. Hewes
is a busy man, so before sending a note to this mailbox, please
consider whether the general discussion list (tpc-rp@aarnet.edu.au)
mentioned earlier might not be a more appropriate forum.
3.5.1: Do I really need an IP-connected machine?
Not really. Technically, just about any computer on the Internet could
run a remote printer server. However, we recommend that the computer
have IP-connectivity, since this tends to make the service faster than
with systems connected with polling mechanisms like UUCP. Still, the
tpc.int subdomain is not picky and if you can provide service for an
area that would otherwise not have it, welcome aboard! The more
important requirement is that you have fax spooling software available
for your computer.
3.5.2: "Is there software available?
Yes, have a look at http://www.tpc.int/devel_corner.html
You may have to try this site a few times, as nameserver timeouts
getting to England from afar have been a problem in the past.
An openly available implementation can be found on
site: ftp.tpc.int
area: tpc/
file: rp.tar.Z
Be sure to retrieve it in BINARY mode, eh?
In addition, if you're running Innosoft's PMDF software for OpenVMS,
then you can contact them at service@innosoft.com for the details.
Also, if you're a vendor who adds support for remote-printing to your
software, we want to hear from you.
3.5.3: What's in the openly available software?
It contains pointers to existing openly available software along with
some "glue" software for BSD-derived UNIX systems.
For sites that want to run remote printer servers, there is support for
both the openly available FlexFAX package and the Bristol Group's IsoFax
product. FlexFAX has recently had a name change - HylaFAX is different
enough that many of the scripts will have to re-written. If you have
done this, Arlington Hewes wants to hear from you!
For sites that want to use remote printing, there are some scripts,
primarily for MH users. If you are willing to contribute to the openly
available software package, we'd love to hear from you. For example,
we'd love to see Mac clients, a Z-mail macro, or a new LISP
interpreter/mail agent written entirely in sendmail rewrite rules.
4.1: And what does TPC stand for?
Go rent the film "The President's Analyst", Paramount Pictures, 1967.
4.2: "And what's with the post horn for a logo?
Go read Thomas Pynchon's "The Crying of Lot 49", Harpers and Row (New
York, 1986).
5.1: How do I contact a cell's operator?
Look at the message you received to see what system processed your FAX
(i.e., the system from which the reject message was sent). Then send
mail to postmaster@that-system.
For the NYC area, this will turn out to be postmaster@tink.com (aka
bob@tink.com) --- me.
contributor - Bob Tinkelman
** Alternatively, try faxmaster@that-system. Cell operators are
required to set up an alias for just this reason - DPN **
5.2: A message from the server comes back saying "unrecoverable
error" or "local configuration error". What does this mean?
It could mean many things, but indicates a problem with the cell itself
usually. You should contact the cell administrator (see 5.1)
-DPN
5.3: We're considering setting up a cell. What benefit will there be for us?
What benefit will there be for whom? The Internet users: the benefit is that
they can transparently send email to people who only have a fax machine.
For the service provider that sets up the gateway:
- there are no direct benefits because it is difficult to charge the email
originator for sending the fax. The problem is dual: administrative (how do
you charge 10 cents to someone that just sent one fax from across the
country or worse, across the planet); security related (given that plain
email does not provide authentication of the originator, how can you be sure
that you are charging the right person?)
- However your service provider can use the fax cover to make
advertisements. These can be either sold to third parties, or this could be
advertisements to the service provider itself. In fact ever since I setup my
gateway for Lisbon, I've had several people call me up and asking how they
could connect to the Internet directly - if I were a service provider this
would have pleased me :-)
contributor - Pedro Ramalho Carlos
5.4: Okay, but how much will it cost?
The costs are not very high:
+ setting up and maintaining the gateway
+ local telephone connection costs (in the US this can be nil in some
cases as I understand)
+ keeping up with "terrorists" that abuse the system to mass faxing and
so on, and explaining this to the abused ones. (This is probably the
largest cost, but I've been quite lucky until now)
contributor - Pedro Ramalho Carlos
5.5: Is this mailing list archived?
Try ftp.aarnet.edu.au:/pub/mailing-lists/tpc-rp-*
I've added a note about this to the mailing list info file so people will
be told when they subscribe.
contributor - Andy Linton
5.6: How can I FAX images again?
One way, to fax an image is by converting it to PostScript and then sending
it just like any other PostScript message (using Mime). There are a number
of (bitmap) convertors to PostScript, one of them is pnmtops. So to send
a GIF, you first convert it to ppm (giftoppm) and then this ppm to ps
(pnmtops).
This should work, since all cells understand PostScript. The only caveat
is that the size of the message sometimes is limited as well, either
by your local mailer, a mailer in between you and the local cell or the
local cell itself.
Other formats are not guaranteed to be understood by the local cell.
You can of course always try to send a TIFF image (using Mime) since this
is mentioned as well in the FAQ, but I have not tried it extensively yet
and I think it didn't work when I tried it a year ago or so.
You can also contact the local cell administrator and ask which formats
are understood by its cell.
Contributor - Bart Swennen
1. Create the graphics with your favorite package.
2. Save it as a postscript file
In Windows you'll be able to this from any application by "printing" the
to file, using a Postscript Printer driver.
3. Verify that the Postscript file doesn't have very long lines (and
especially from Windows, that it does not begin with Ctrl-D)
4. Send the file as an application/postscript MIME body part to the RP
address...
Contributor - Pedro Ramalho Carlos
5.7: But Eudora doesn't seem to send postscript files correctly!
Thanks to all who helped with my PS faxing problems. The solution was that
Eudora 1.4 does not send PS files intact with control characters. 1.43
works quite well for PS to tpc faxing.
Contributor - Rick Wintersberger
In Eudora, use the AppleDouble format for attachments, with "Always as
Documents" unchecked. This should be your default setting for maximum
interoperability with non-Mac MIME readers. This should cause the body
part to be sent as application/postscript. I'll attach this test file here
(a box with a diagonal line inside). I used "Level 1 Compatible" "ASCII"
output with "Format: Postscript Job" (not EPS). I also have LaserWriter 8
v1.1 drivers.
Note that if you have fonts in your document and don't know what kind of
printer the eventual output will be done on, you are better off including
all fonts in the file (the default is to include none). This makes it
bigger, but you are more likely to get results that match what you expect.
If you use a lot of fonts, though, you can overwhelm a rasterizer and
perhaps the document won't print at all, so be careful.
One other thing...naming the file with a .ps at the end should help foreign
systems understand what they're getting. I don't think Eudora looks at
filename extensions when sending. I think it does use them to set Mac
type/creator pairs when receiving attachments, though.
In Eudora, use the AppleDouble format for attachments, with "Always as
Documents" unchecked. This should be your default setting for maximum
interoperability with non-Mac MIME readers. This should cause the body
part to be sent as application/postscript. I'll attach this test file here
(a box with a diagonal line inside). I used "Level 1 Compatible" "ASCII"
output with "Format: Postscript Job" (not EPS). I also have LaserWriter 8
v1.1 drivers.
Contributor - Tom Maufer tom.maufer@gsfc.nasa.gov
Hardware for Remote Printing kindly provided by the folks at
Netcentric Corporation - http://www.netcentric.com/
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