comp.dcom.fax FAQ (Frequently Asked Questions) -- Part 1 of 2 ------------------------------------------------------------- January 1994 This article contains the answers to some Frequently Asked Questions (FAQ) often seen in the USENET newsgroup comp.dcom.fax relating to facsimile standards, software, and hardware. It will be posted approximately monthly. If you would like to make any submissions or corrections to the FAQ, please contact faxfaq@faximum.com. Your input is greatly appreciated. Suggested questions need not be accompanied by suggested answers. Areas that are in particular need of contributions are marked "". Flames and other comments (constructive or otherwise) are also welcomed. Note that this FAQ is primarily concerned with fax standards in general and computer-based fax in particular. It contains little information on commercial fax machines and related paraphenalia. If someone else would like to start and maintain such a section (or separate FAQ) they are more than welcome to do so. Otherwise, please send contributions to this FAQ. regards g. pajari@Faximum.COM George Pajari / Faximum Software / Tel: +1 (604) 925-3600 / Fax: ... 926-8182 1497 Marine Drive, Suite 300 / West Vancouver, BC / Canada V7T 1B8 Std. Disclaimers: ---------------- The content of this article is the sole responsibility of the author(s) and contributors, and does not necessarily represent the opinions or policies of their employers or other companies mentioned. The information provided herein is believed to be correct but the author and contributors cannot accept any liability for errors and omissions. Readers are cautioned to verify any information before making decisions or taking action based upon this information. While every reasonable effort has been taken to maintain an objective and unbiased approach in the collection and presentation of this information, readers are advised that the author and possibly some of the contributors work for or have an interest in commercial organisations involved in the fax and/or computer industry. ================= TABLE OF CONTENTS ================= Note that this FAQ has grown to the point where it has been split into two parts. Part 1 contains the front matter (introduction, disclaimer, etc.) and the glossary. Part 2 contains everything else (questions and answers, sources of information, and information on products). ----- Part 1 of 2 [This part] ----- G. Glossary and Background Information ----- Part 2 of 2 [The other part] ----- Q. Frequently Asked Questions Q.1 Can I use my * data modem to send/receive faxes? Q.1A Can my fax modem transmit data? Q.2 How can I fax PostScript or PCL documents using computer-based fax? Q.3 How can I view incoming faxes on my computer? Q.4 How can I print incoming faxes on my computer? Q.5 Can fax modems also handle data or voice calls? Q.6 What resolution are fax images? Q.7 Can I take a fax file and edit it? Q.8 Is there a standard program interface (API) for fax communications? Q.9 How can I share my single phone line with voice, fax, data, etc. I. Sources of Information I.1 Standards Related to Facsimile Communication I.2 Where to Obtain Standards Documents and Related Information I.3 Magazine Reviews of UNIX Fax Software I.4 Magazine Reviews of DOS/Windows Fax Software I.5 Magazine Reviews of Mac Fax Software I.6 Magazine Reviews of Fax Modems (see also O/S specific reviews) I.7 Magazine Reviews of Fax Machines I.8 Publications Devoted to Fax and Telecommunications I.9 Books on Fax I.10 Other Sources of Information on Fax I.11 Conferences on Fax I.12 Associations Related to Fax Technology I.13 Fax-on-Demand Phone Numbers P. Product Information P.1 List of UNIX Fax Software P.2 List of MS-DOS Fax Software P.3 List of MacIntosh Fax Software P.4 List of Windows Fax Software P.5 List of OS/2 Fax Software P.6 List of Fax Modem Vendors P.7 List of Fax Board Vendors P.8 List of Vendors of Secure Fax Equipment =============================================================================== Subject: G. GLOSSARY and BACKGROUND INFORMATION =============================================================================== ANSI/AIIM MS53-1993 The American National Standard File Format for Storage and Exchange of Images - Bi-Level Image File Format: Part 1 (ANSI/AIIM MS53-1993) was approved in 1993. The standard defines a format for a file containing one page with one image. Page sizes and image sizes can be specified. Both definite length and indefinite length are supported. Clipping of the image can be specified. Image coding may be according to ITU-T Recs. T.4 (one- and two-dimensional) and Rec. T.6. Bitmap may also be specified. Both facsimile style least significant bit and industry style most significant bit mapping are supported. (Definition courtesy of hrs1@cbnewsi.cb.att.com (herman.r.silbiger)) BFT or Binary File Transfer A method of transferring files using fax modems (as an extension to the fax protocol). This standard, which will be approved shortly, will be referred to as T.434. Brooktrout Patent (taken from a press release from Brooktrout) Brooktrout's patent (number 4,918,722), issued by the US patent office in 1990, covers generally any method for the selection of facsimile messages and their deliver to a particular telephone number under control of commands entered through a telephone, for example in the form of signals generated from the telephone's touch-tone keypad. This method is employed in many fax-on-demand systems, which provide business users and service providers the ability to offer automated fax delivery of specified information in response to requests from customers, subscribers or other callers. [Editor's note: this patent is the subject of litigation and the current status or validity of this patent is not known.] CAS An API for fax devices invented by Intel and DCA and tied to the Intel and MS-DOS architectures. CCITT Comite Consultatif International Telegraphique et Telephonique (a.k.a. The International Telegraph and Telephone Consultative Committee). The old name for ITU-T, the body responsible for setting the international standards for telecommunications equipment. See ITU below. CED or Called Station Identifier The distinctive tone generated by a Group III fax machine when it answers the phone (2100 Hz). Class 1 The Class 1 fax modem standard describes an extension to the "Hayes Modem Command Set" to permit computers to send and receive faxes using fax modems. The Class 1 standard is a low-level specification in which most of the protocol work (i.e. T.30) as well as image generation (rasterising and T.4 compression) must be done by the computer (in software) while the modem only handles the basic modulation as well as converting the asynchronous data from the computer into the synchronous packets used in fax communications. The primary advantage of Class 1 modems is that fax protocol is implemented in software which means that new extensions to the fax protocol standard (i.e. T.30) can be implemented without requiring a ROM change in the modem (or without waiting for the modem manufacturer to get around to supporting the new feature). Also software developers are not dependent on the quality of the T.30 firmware in the modem (as are developers who use Class 2 modems). The primary disadvantages are (a) the software vendor has to handle the complexity of the T.30 protocol and (b) Class 1 is very sensitive to timing and multi-tasking operating systems (such as *IX) have great difficulty in reliably meeting the tight timing constraints and maintaining the fax connection. Lifting this timing limitation is the primary motivation behind the new proposed Class 4 standard. The official standard for Class 1 is EIA/TIA-578. Although the official standard is copyright EIA/TIA/ANSI, a draft version has been published electronically by Supra and is available from their BBS (see section I.10 for the number) and from Sam Leffler at SGI (retrieve his FlexFax package, described in section P.1). Class 2 The Class 2 fax modem standard describes an extension to the "Hayes Modem Command Set" to permit computers to send and receive faxes using fax modems. The Class 2 standard is a higher-level specification in which most of the protocol work (i.e. T.30) is done by the modem while the computer is responsible for managing the session and providing the image data in the appropriate format (i.e. T.4). The primary advantage of Class 2 is that the low-level detail work is handled by the modem. Not only does this mean that software developers do not have to be burdened with having to support the T.30 protocol, it also relieves the host computer of all of the time-critical aspects of fax communications, making support of Class 2 modems under *IX systems possible. The biggest headache for software developers is that the Class 2 standard took a long time to be approved (more for political than technical reasons, IMHO) and many companies did not wait for the final version to be approved before shipping modems. As a result we have a situation (as of 93Q4) in which all shipping Class 2 modems adhere (more or less) to the first draft of the TR29.2 committee (document SP-2388) and not to the standard as it was approved. To compensate for this, the "new" Class 2 is referred to as Class 2.0 and the "old" as plain Class 2. (Warning - flame from a frustrated fax programmer on...) Even more disconcerting is the fact that most companies who have implemented (the old) Class 2 have done one or more things wrong (they must have been smoking *and* inhaling) so we have a further division of the standard into "true, old Class 2" (which includes the Everex 24/96D and MultiTech modems) and everything else (mostly based on the Rockwell chip which differs from SP-2388 in a number of ways, although some other chip makers, such as EXAR, have found even more ways than Rockwell to depart from SP-2388). It's so bad that most modem companies now implement the Rockwell version of Class 2 just because so many of the *%#& things have been shipped (i.e. Multitech has a special command which switches their modem from proper Class 2 operation to Rockwell-like operation just so they can interoperate with DOS software that expects Rockwell-like operation). And of course no one at Rockwell or EXAR or the other companies bothered to write down the difference between their version of Class 2 and the TR29.2 document. (Flame off.) The draft standard for the "old" Class 2 is SP-2388, Document TR-29/89-21R8, dated March 21, 1990. This is available by contacting the EIA/TIA directly. This is the standard implemented by all Class 2 modems on the market prior to the end of 1993. The official standard for the "new" Class 2 (also referred to as Class 2.0) is EIA/TIA/ANSI-592. This document is available from Global Engineering Documents (see below). There are rumours of 2.0 modems shipping but as of January 1994 none of those tested by the editor of this FAQ were ready for prime time. Note that although many modems that implement Class 2 also support Class 1, Class 1 is *not* a subset of Class 2. Also, there are some modems that only support Class 2 and many that only support Class 1. Although the official standard is copyright EIA/TIA/ANSI, a draft version has been published electronically by Supra and is available from their BBS (see section I.10 for the number) and from Sam Leffler at SGI (retrieve his FlexFax package, described in section P.1). Class 3 A class number reserved for a project to define a standard for fax modems that would, in addition to handling the T.30 protocol (i.e. Class 2), also handle the conversion of ASCII data streams into images (i.e. T.4). Although there are a couple of fax modems that handle the ASCII to fax conversion, no draft document has been circulated and the future of this project is in doubt. Class 4 Class 1 with intelligent buffering to reduce the need for the host computer to respond instantly to the fax modem. This standard is expected to go out to ballot in 94. Class 8 Not a fax standard at all but an extension to the Hayes command set to support voice. CNG or Calling Tone The distinctive tone that a fax machine ought to generate when placing a fax call (1100 Hz on for 1/2 second, off for 3 seconds). Note that the Group 3 fax standard only requires fax machines in "automatic operation" to generate this tone so that machines which require you to dial the number (either on the keypad of the fax machine or using an attached phone) need not generate this tone. The lack of CNG can cause some fax switches (see Q.9 below) problems. There has ben a proposal to change the Group 3 standard to mandate CNG on all fax calls. CSI or Called Subscriber Information The "name" of the answering fax machine. An optional frame of information sent to the calling fax machine during Phase B (see T.30 below). Although many fax machines permit ASCII information, the T.30 standard states that this is to contain the international phone number of the fax machine, including the plus symbol, the country code, the area code, and the subscriber number using only digits, the plus symbol, and a space. (i.e. the North American fax number (604) 926-8182 ought to be programmed into the fax machine as +1 604 926 8182). ECM or Error Correcting Mode An extension to T.30 to permit the receiving fax machine to request that portions of an image that were received with errors be retransmitted. Normally the T.4/T.30 protocol is error detecting but not error correcting. The receiving fax machine can usually tell when an error has impaired the image but cannot selectively request retransmission of the damaged portions of the image. The only options are to (a) ignore the errors (if few in number), (b) request that the page be resent (ignored by most fax machines), or (c) give up. EIA/TIA The Electronics Industry Association and the Telecommunications Industry Association. The U.S. bodies responsible for the development of standards related to telecommunications in general and for fax in particular. EIA/TIA-465 The US version of T.4 (will probably be accepted as T.4 in the near future). EIA/TIA-466 The US version of T.30 (will probably be accepted as T.30 in the near future). EIA/TIA-530 The US version of something or other related to fax. . EIA/TIA-578 See the definition of Class 1 (above). EIA/TIA-592 See the definition of Class 2 (above). EIA/TIA-602 The ANSI/EIA/TIA standard for the "Hayes Command Set" for modems. FaxBios An industry consortium (including companies such as Everex, HP, WordPerfect, etc.) that has published a specification for a FAX API. Versions for DOS and WINDOWS have been developed and discussions continue on adapting this API to other operating systems. With the demise of Everex the association seems to have collapsed leaving WordPerfect as the only significant company supporting and promoting the FaxBios standard. Group I Fax An old (now obsolete) standard for fax machines in which a page was transmitted in about six minutes at a resolution of 98 scan lines/inch. Group I devices frequently worked by attaching the page to be transmitted to a rotating drum (at 180 rpm) along which a photocell moves. Either amplitude modulation (the blacker the pixel the louder the tone) or frequency modulation (the blacker the pixel the higher the tone) can be used. The gory details may be found in ITU-T Recommendation T.2. Group II Fax An old (now almost obsolete) standard for fax machines in which a page was transmitted in about three minutes at a resolution of 100 scan lines/inch. Group II uses vestigial sideband amplitude modulation with phase shifts. A white pixel is represented by a louder tone. Group III One of the current standards for fax machines in which a page is transmitted in about one minute. See the definition of T.30 (below) for more details. Group IV A standard for fax transmission using ISDN at 64kbps. ITU and ITU-T The International Telecommunication Union (ITU) is the United Nations specialized agency dealing with telecommunications. The purposes of the ITU as defined in the Convention are: - to maintain and extend international cooperation for the improvement and rational use of telecommunication of all kinds; - to promote the development of technical facilities and their most efficient operation with a view to improving the efficiency of telecommunication services, increasing their usefulness and making them, so far as possible, generally available to the public; - to harmonize the actions of nations in the attainment of those common ends. The ITU works to fulfil these basic purposes in three main ways: 1. international conferences and meetings; 2. technical cooperation; 3. publication of information, world exhibitions. The ITU is an organization, a union, of Member countries. As of 1993 there were 166 Members. The Union's headquarters are in Geneva, in the Place des Nations. Before 1993, the ITU consisted organizationally of five permanent organs: the General Secretariat, the International Frequency Registration Board (IFRB), the International Radio Consultative Committee (CCIR), the International Telegraph and Telephone Consultative Committee (CCITT) and the Telecommunications Development Bureau (BDT). In early 1993, the ITU was reorganized into the General Secretariat and three Sectors: Radiocommunication, Telecommunication Standardization and Telecommunication Development. The standards-making activities of the CCITT and CCIR have been consolidated into the Telecommunication Standardization Sector (ITU-T). The remainder of CCIR activities were integrated with the activities of the IFRB into the Radiocommunication Sector (ITU-R). The Development Sector (ITU-D) facilitates telecommunications development by offering technical cooperation and assistance. The ITU General Secretariat supports the activities of the three Sectors. (This description has been taken from material published by the ITU.) The standards promulgated by the ITU-T are called Recommendations and the recommendations of relevance to the fax world are the T series which govern the fax protocols and the V series which govern modem operation. (See also T.*, and V.*, below.) For more information on the ITU and the publications available from them, see the description of ITUDOC in section I.10 in Part 2 of this FAQ. MH or Modified Huffman compression Also known as Group III one-dimensional compression. See T.4. MR or Modified READ compression Also known as Group III two-dimensional compression. See T.4. One-Dimensional Compression See T.4 SP-2388 The first draft standard for Class 2 that was implemented by many companies while waiting for the final standard to be approved (see also the definition for Class 2 above). T.1 See Group I Fax. Not to be confused with T-1, a digital telephony standard that runs at 1.544 Mb/s (at least in North America). T.4 One of the recommendations (i.e. standard) for Group III fax. In particular, this recommendation covers the page size, resolution, transmission time, and coding schemes supported for Group III fax. (See also the definition of T.30 below.) The basic coding scheme (called in the recommendation "One-dimensional coding scheme" but also known in the industry as MH or Modified Huffman) takes each scan line of pixels and compresses it by (a) converting the raster in a sequence of run lengths (the number of white pixels followed by the number of black pixels followed by the number of white pixels etc. and etc. until the entire raster has been converted into runlengths) and (b) encoding each run length into a unique variable-length bit string. The code words used for white and black runlengths are different and have been chosen in order to do a reasonable job of compressing a "typical" fax page. For example, in one dimensional encoding the following raster: OOOOOOOOOO****OOOOOO**OOOOOOO*OOOOOOOOO***... converted into run lengths: 10 4 6 2 7 1 9 3 ... encoded into MH bit strings: 00111 011 1110 11 1111 010 10100 10 (spaces have been added for readability and are not part of the MH bit string) Since our example has unusually short white run-length it does not accurately illustrate the degree of compression which can be achieved. For example, a normal fine resolution fax image contains about 3,800,000 pixels (464K). Using one-dimensional encoding this can be reduced to between 20K - 50K. In two-dimensional encoding, the first line of a group of lines is compressed using one-dimensional coding (see above) and subsequent lines are compressed using an algorithm that describes line n in terms of line n-1. Since there is usually a high-degree of correlation between the pixels of adjacent scan lines, this usually results in significant compression. Since the basic fax protocol (T.30) is error detecting (but not error correcting), there is a limit on the number of two-dimensionally compressed scan lines that can follow a 1-D line. This is to limit the propagation of errors through an image. This limit is referred to as 'k' in the standard and is 2 for standard-resolution faxes and 4 for high-resolution faxes. Unfortunately, this method of compression is computationally intensive and most (inexpensive) fax machines do not support it. T.6 The recommendation that covers the image compression algorithm used for Group IV fax machines. T.6 is essentially the two-dimensional compression algorithm from T.4 (see above) except that 'k' is infinite (i.e. all lines are two dimensionally compressed). This can be done because Group IV fax machines operate over an error-free communications channel. T.30 One of the recommendations (i.e. standard) for Group III fax. In particular, this recommendation covers the protocol used to manage the session and negotiate the capabilities supported by each fax machine. The details of the image format are covered by the T.4 recommendation (see above). The protocol describes each fax call as proceeding through five phases: A: Call Set-Up This phase covers the placing of the call on the PSTN and the distinctive tones the calling and called stations are to emit. B: Pre-Message Procedure for Identifying and Selecting Facilities During this phase the two fax machines: - agree on whether to use tones or binary codes to exchange information on capabilities (most current fax machines use binary codes) - (optionally) the called machine sends a CSI frame identifying it to the calling machine. - the called machine sends a DIS frame telling the calling machine what capabilities it has (i.e. resolution, page size, receiving speed, etc.) - (optionally) the calling machine sends a TSI frame identifying it to the called machine. - the calling machine sends a DCS frame telling the called machine what capabilities are in effect for this document (based on the calling machine's capabilities and the information received in the DIS frame). - the two machines determine the maximum baud rate that the communications link will reliable sustain (training & phasing) C: Message Transmission The fax is sent. The end of the last scan line is marked by a RTC code (return to control). D: Post-Message Procedure including End-of-message, Confirmation, and Multi-Page Procedures - the calling machine indicates what it wants to do next (send another page, terminate the call, request operator intervention, etc.). - the called machine indicates its response to the page and command just received (o.k., o.k. but retrain, not o.k., give up, etc.) At this point the machines go to one of phase B, C, or E depending on the exchange of commands and responses during phase D. E: Call Release Hang up the phone. T.434 The standard for Binary File Transfer Format (a method of encoding documents and sending them by fax without converting them to image format first. T.611 A standard for high-level fax API. TSI or Transmitting Subscriber Information The "name" of the calling fax machine. An optional frame of information sent by the calling fax machine during Phase B (see T.30 above). See CSI (above) for details on the recommended format. Two-Dimensional Compression See T.4. V.17 The ITU-T recommendation for 14,400 bps *synchronous* half-duplex modems. Used during the image transmission phase of fax communications. Optional (most fax machines do not support V.17). V.22bis The ITU-T recommendation for 2400 bps asynchronous full-duplex modems. (Not used in fax but frequently supported by modems that handle fax.) V.27ter The ITU-T recommendation for 2400 and 4800 bps *synchronous* half-duplex modems. Used during the image transmission phase of fax communications. V.29 The ITU-T recommendation for 7200 and 9600 bps *synchronous* half-duplex modems. Used during the image transmission phase of fax communications. V.32 The ITU-T recommendation for 9600 bps asynchronous full-duplex modems. (Not used in fax but sometimes supported by modems that also handle fax.) V.32bis The ITU-T recommendation for 14,400 bps asynchronous full-duplex modems. (Not used in fax but sometimes supported by modems that also handle fax.) V.42 The ITU-T recommendation for error-checking and correction. (Not used in fax but sometimes supported by modems that also handle fax.) V.42bis The ITU-T recommendation for data compression. (Not used in fax but sometimes supported by modems that also handle fax.) X.5 The ITU recommentation for a Fax PAD facility in a public data network. X.38 The ITU recommentation for a Group 3 fax equipment/DCE interface for equipment accessing the fax PAD facility in a public data network. X.39 The ITU recommentation for procedures for the exchange of control information and user data between a fax PAD facility and a packet mode DTE. -------------------------------------------------------------------------- Copyright 1994 Faximum Software Inc. All Rights Reserved. Permission is granted to copy or distribute this faq (in whole or part) for non-commercial purposes as long as the copyright notice is reproduced and acknowledgement given. Requests for permission for commercial reproduction or distribution (if you are uncertain if it is commercial, ask) should be mailed to the author: pajari@Faximum.com -------------------------------------------------------------------------- ------------------------------------------------------------------------------- comp.dcom.fax FAQ (Frequently Asked Questions) -- Part 2 of 2 ------------------------------------------------------------- January 1994 This part of the FAQ (part 2) contains lists of: - questions and answers; - sources of information; and - information on products. Part 1 contains the introduction to the FAQ, the disclaimer, and the definitions of common terms and various background information on fax. ================= TABLE OF CONTENTS ================= ----- Part 1 of 2 [The other part] ----- G. Glossary and Background Information ----- Part 2 of 2 [This part] ----- Q. Frequently Asked Questions Q.1 Can I use my * data modem to send/receive faxes? Q.1A Can my fax modem transmit data? Q.2 How can I fax PostScript or PCL documents using computer-based fax? Q.3 How can I view incoming faxes on my computer? Q.4 How can I print incoming faxes on my computer? Q.5 Can fax modems also handle data or voice calls? Q.6 What resolution are fax images? Q.7 Can I take a fax file and edit it? Q.8 Is there a standard program interface (API) for fax communications? Q.9 How can I share my single phone line with voice, fax, data, etc. I. Sources of Information I.1 Standards Related to Facsimile Communication I.2 Where to Obtain Standards Documents and Related Information I.3 Magazine Reviews of UNIX Fax Software I.4 Magazine Reviews of DOS/Windows Fax Software I.5 Magazine Reviews of Mac Fax Software I.6 Magazine Reviews of Fax Modems (see also O/S specific reviews) I.7 Magazine Reviews of Fax Machines I.8 Publications Devoted to Fax and Telecommunications I.9 Books on Fax I.10 Other Sources of Information on Fax I.11 Conferences on Fax I.12 Associations Related to Fax Technology I.13 Fax-on-Demand Phone Numbers P. Product Information P.1 List of UNIX Fax Software P.2 List of MS-DOS Fax Software P.3 List of MacIntosh Fax Software P.4 List of Windows Fax Software P.5 List of OS/2 Fax Software P.6 List of Fax Modem Vendors P.7 List of Fax Board Vendors P.8 List of Vendors of Secure Fax Equipment =============================================================================== Q. Frequently Asked Questions =============================================================================== Q.1 Can I use my * data modem to send/receive faxes? ------------------------------------------------------------------------------- In a word, no. Unless your data modem has specific additional support for fax, you cannot communicate with fax devices using a data (only) modem. Simply put, the problem is that the modulation methods (tones) used to communicate data are different from those used to communicate faxes. Typically the modulation schemes used for fax are synchronous half-duplex while those used for data (at least by most UNIX and PC people) are asynchronous and full-duplex. Also, data modems, once they have negotiated a modulation scheme, tend to continue with the same one through out the session. Fax modems switch before and after each page between a high-speed modulation scheme used to transmit the image data and a lower (300 or 2400 bps) scheme to exchange control information. The following table outlines this briefly (see also part 1 of this FAQ for definitions of V.*). Data Rate Data Modulation Std. Fax Modulation Std. ========================+==========================+======================== 9,600 bps | V.32 | V.29 ------------------------+--------------------------+------------------------ 14,400 bps | V.32bis | V.17 ========================+==========================+======================== ------------------------------------------------------------------------------- Q.1A Can my fax modem transmit data? ------------------------------------------------------------------------------- In a word, maybe. There is a standard proposed by the EIA/TIA/ANSI called Binary File Transfer (BFT) that extends the fax Group III modulation and protocols for bulk data transfer. The problem, of course, is that few fax modems or software packages provide support for this mechanism. ------------------------------------------------------------------------------- Q.2 How can I fax PostScript or PCL documents using computer-based fax? ------------------------------------------------------------------------------- In addition to the basic software to drive your fax modem/board, you will need specific software that can convert PostScript or PCL files into a raster image format compatible with your fax software package. GhostScript, for example, is a publically available software package that can convert PostScript into raster image format (although there are varying opinions on the quality of the font support). In the commercial world, most of the vendors of fax software provide software that can handle PostScript and/or PCL. When purchasing such software (a) check how many different fonts are supported (it's a pain to be able to use, say, NewCentury on your laser printer only to find it is not included in your fax package), and (b) in the case of PCL, check which level of the language is supported (PCL-4 does not support scalable fonts, PCL-5 does). ------------------------------------------------------------------------------- Q.3 How can I view incoming faxes on my computer? ------------------------------------------------------------------------------- In the PD world, there are a number of image-viewing packages available for X (such as xv). In the commercial world, most fax vendors provide support for the commonly available devices (in the case of UNIX, X; in the case of PC-UNIX, VGA and HGA support. Some vendors support other graphics-capable terminals such as the Wyse WY-160.) ------------------------------------------------------------------------------- Q.4 How can I print incoming faxes on my computer? ------------------------------------------------------------------------------- Most fax software packages include software to convert fax images into print data streams compatible with dot matrix, HP PCL, or PostScript printers. Also the publically available (where?) pbmplus filter kit will handle most image formats. ------------------------------------------------------------------------------- Q.5 Can fax modems also handle data or voice calls? ------------------------------------------------------------------------------- Not all fax boards can handle data (some are fax only). Most (all?) external fax modems can handle data as well as fax. Some (but not all) fax modems and software can automatically distinguish between data and fax calls and answer them appropriately Some DOS/WINDOWS based products can automatically distinguish between voice and fax/data calls and operate as a digital answer machine as well as a fax machine. Also, several companies sell devices which can switch incoming calls between a fax machine, a telephone answering machine, and a modem. [Suggestions anyone?] ------------------------------------------------------------------------------- Q.6 What resolution are fax images? ------------------------------------------------------------------------------- The standard resolution for faxes is 3.85 scan lines/mm (approx. 98 dpi vertically) with 1728 pixels across a standard scan line of 215 mm (approx. 204 dpi horizontally). The optional "fine" resolution is 7.7 scan lines/mm (approx. 196 dpi vertically) with the same horizontal resolution. Many Group III fax machines use non-standard frames to negotiate higher resolutions (typically 300x300 dpi and 400x400 dpi) with other fax machines by the same manufacturer. Two fax machines (or modems) must negotiate a common resolution, page width, and page length before sending each page. The standard requires that all Group III fax machines suppport at least standard resolution and A4 size so that common ground can always be found. Extensions to the Group III standard to support these higher resolutions in a standard way have been proposed. Their current status is not known . . ------------------------------------------------------------------------------- Q.7 Can I take a fax file and edit it? ------------------------------------------------------------------------------- When faxes exchange information, it is done in the form of compressed images (with the exception of BFT). If you wish to edit or otherwise manipulate a received fax file you have two options: 1 - edit the file using a "paint" program that will accept the fax file (unfortunately there is a wide range of file formats for image files and you may have to work to find a format that is common between your fax application and your paint program). 2 - pass the file through an OCR program that will attempt to convert the image into ASCII (or word processing file format). The problem here is that most OCR programs are tuned to work with 300x300dpi images and faxes are either 98x204 or 196x204. ------------------------------------------------------------------------------- Q.8 Is there a standard program interface (API) for fax communications? ------------------------------------------------------------------------------- There are many API's that are used for fax communications. Words marked by -word- are further explained in the glossary in Part 1 of this FAQ. At the hardware level, the two standards that govern the exchange of commands between a host computer and a fax modem are EIA-578 (-Class 1-) and EIA-592 (-Class 2-). At the software level there is one "official" standard and a number of "industry standards". The one "official" standard is ITU-T T.611 (). The most widely known industry standards are -CAS- (Communicating Applications Standard (?)) invented by Intel and DCA and tied closely to the Intel architecture, and -FaxBios- (developed by an industry consortium) which is less machine-dependent (implementations for MS-DOS and WINDOWS have been published and sporadic work on UNIX and other bindings is underway). ------------------------------------------------------------------------------- Q.9 How can I share my single phone line with voice, fax, data, etc. ------------------------------------------------------------------------------- There are a number of devices on the market (suggestions from happy campers welcome) that will try to distinguish between an incoming voice, fax, or data call and route the call appropriately. These fax switches attach to the phone line and then the other devices (your normal voice phone/answering machine, fax machine, data modem, etc.) are attached to the fax switch). All devices work on one of two general principles: listening for CNG or voice, or listening for distinctive ring patterns (cadences). In the first case the device will answer the phone and try to guess what it should do based on what it hears. Some machines play back a sound of a phone ringing so that humans dialling in think the phone is still ringing when in fact the fax switch is listening to see if the call is from a fax machine or a human. If the CNG tone (see Part 1 for a definition of CNG) from the calling fax machine is heard, then the switch connects the call to the fax machine, otherwise the call is deemed to be a voice call and is connected to your phone/answering machine. A slightly more sophisticated approach is for the fax switch to answer the phone and play a short recorded announcement. If, during the announcement the CNG tone is heard, then the call is switched to the fax machine. If no CNG tone is heard but sound is heard after the announcement, then the call is assumed to be voice and switched appropriately. If nothing is heard then the switch either considers the call a data call and switches it to a modem or considers it a fax call from a machine that does not generate a CNG and switches it to the fax machine. The other approach relies upon an optional service available from some telcos called "SmartRing", "Distinctive Ring", "RingMaster", "Ident-a-Ring", etc. This feature allows one to have more than one phone number associated with the same phone line. Incoming calls using the different phone numbers can be differentiated by the different ringing patterns (i.e. one long ring, two short rings, three short rings, etc.) The fax switch distributes the call based on the ring cadence it detects. The advantage of the first approach is that one does not have to send more money to the phone company (or depend upon the availability of the "SmartRing" feature being available). The disadvantage is that it is not always reliable (especially in the face of fax machines that do not generate CNG tones). The advantage of the second approach is that it is very very reliable. The disadvantage is that it requires the availability of the "SmartRing" feature from one's telco as well as sending more money to the telco every month. =============================================================================== Subject: I. Sources of Information =============================================================================== I.1 Standards Related to Facsimile Communication ------------------------------------------------------------------------------- CCITT (now renamed ITU-T) The Blue Book, Volume VII - Fascicle VII.3 Recommendation T.0 - T.63 EIA/TIA/ANSI EIA/TIA-602 Data Transmission Systems and Equipment-Serial Asynchronous Automatic Dialing and Control "This is the standard for the basic Hayes command set." TIA PN-2388 Asynchronous Facsimile DCE Control Standard (DRAFT), Service Class 2, (also known as Document TR-29/89-21R8, March 21, 1990) "The first draft of the Class 2 standard, voted down, but the basis for all current (93Q1) Class 2 modems." EIA/TIA-578 Asynchronous Facsimile DCE Control Standard, Service Class 1 EIA/TIA-592 Asynchronous Facsimile DCE Control Standard, Service Class 2 ------------------------------------------------------------------------------- I.2 Where to Obtain Standards Documents and Related Information ------------------------------------------------------------------------------- EIA/TIA (202) 457-4942 (Yvette Bottoms) Source of draft EIA/TIA standards (final stds available from Global) Global Engineering Documents (800) 854-7179 fax: (202) 331-0960 Distributor for published EIA/TIA standards, as well as ITU-T (CCITT) and standards docs from 400 other organisations and institutions. EIA catalog of standard available at no charge National Technical Information Service (NTIS) (703) 487-4650 Philips Business Information Inc. (has acquired assets of OMNICOM) (301) 424-3338 or 1 (800) 777-5006, FAX: (301) 309-3847 Source of ITU-T (CCITT) and ISO publications UN Bookstore ITU-T (CCITT) Publications +1 (212) 963-7680 or +1 (800) 553-3210 Action Consulting Source of draft communications standards Human Communications (203) 746-4367 FAX: (203) 746-4367 Source of draft communications standards International Telecommunications Union electronic document distribution service (ITUDOC) For more information, send a message with the line HELP in the body to: itudoc@itu.ch ------------------------------------------------------------------------------- I.3 Magazine Reviews of UNIX Fax Software ------------------------------------------------------------------------------- UNIX WORLD, August 1991, pp. 52-60, "Four Fitting Fax Packages", Rick Farris Reviews DigiFax, Faximum, TruFax, and VSI-Fax UNIX REVIEW, V10n11, Nov 1992, pp. 63-76, "Just the Fax, Ma'am", Tim Parker Reviews ArnetFAX, DigiFax, Faximum, FaxLink, FaxTrax, VSI-Fax ------------------------------------------------------------------------------- I.4 Magazine Reviews of DOS/Windows Fax Software ------------------------------------------------------------------------------- PC Magazine, 8 Dec 1992, v11n21, p275-342, "The Fax Solution", by Joel Dreyfus Reviews BitFax, DosFax Pro, Eclipse FAX, FAXability Plus, Faxit for DOS Faxit for Windows, FaxMaster, Fax Talk Plus, The Fax Window, Mirror III Fax, MTEZ Standard with ExpressFax, PaperWorks, and SuperFax for Windows. PC World, Feb 1993 v11n2, "Windows Fax Software", by Bryan Hastings The article discusses: Bit Software Bit Fax/OCR for windows v2.05; Caere Fax Master 1.01; Delrina WinFax Pro 3.0; Ellipse Fax 1.2; Intel Faxability plus/OCR 1.0; Softnet Faxit 2,.15e; and Zsoft Ultrafax for Windows 1.0. BYTE, Jan 1993, v18n1, p62-64, "First Impressions", by David Andres Discusses Delrina's WinFax Pro 3.0 BYTE, Jan 1993, v18n1, p68, "First Impressions", by Dick Pountain Discusses Trio's Datafax ------------------------------------------------------------------------------- I.5 Magazine Reviews of Mac Fax Software ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- I.6 Magazine Reviews of Fax Modems (see also O/S specific reviews) ------------------------------------------------------------------------------- PC Magazine, 8 Dec 1992, v11n21, p343-361, "Negotiating the Fax Modem Jungle" by Rick Ayre Reviews Computer Peripherals, Hayes, Intel, Practical Modem, Supra, U.S. Robotics, and Zoom. NeXTWorld Magazine, Winter 1992, v2n4, p59-60, "Just the Fax" by Simson L. Garfinkel Reviews Dove, HSD, and ZyXEL. ------------------------------------------------------------------------------- I.7 Magazine Reviews of Fax Machines ------------------------------------------------------------------------------- Consumer Reports, Nov. 1993, v58n11, p722-728, "Fax machines" A general consumer product review of various fax machines. The article reviews in detail 13 lower-end (i.e thermal paper) fax machines and comments on a couple of higher-end (i.e. plain paper) machines. The Panasonic KX-F230 and the Brother 600 were rated "Best Buys". Get the article to see where the rest ended up and why (reprinting the entire list of ratings would exceed my interpretation of "fair use" w.r.t. copyright). ------------------------------------------------------------------------------- I.8 Publications Devoted to Fax and Telecommunications ------------------------------------------------------------------------------- Communications Standards Review [10-12/year, $695/year in N.A.; partial or shorter subs avail., contact publisher] 757 Greer Road, Palo Alto, CA 94303-3024 USA Phone: +1-415-856-9018 Fax: +1-415-856-6591 e-mail: 72540.113@Compuserve.Com Communications Standards Review is a journal providing current technical information on work in progress on communications standards (including fax) in US and international standards forums. EMMS [Bi-weekly, $595 per year] published by Telecommunications Reports 1333 H Street, 11th Floor Washington DC 20005 Phone: (202) 842-0520 Fax: (202) 842-3047 Human Communications Digest, [Quarterly, $195 per year within US, contact publisher for outside US] published by Human Communications 12 Kevin Drive, Danbury CT, 06811-2901 Phone: (203) 746-4367 FAX: (203) 746-4367 A digest of recent developments with fax and related standards. NetFax News, published by Davidson Consulting [Monthly, $contact publisher] 530 N. Lamer Street, Burbank, CA, 91506 Phone: (818) 842-5117 FAX: (818) 842-5488 Also publishes Scouting Reports and Buyers' Guides Fax Focus [weekly, $250, free with membership in the AFA) published by the American Facsimile Association Phone: (215) 963-9110 Fax: (215) 451-1156 ------------------------------------------------------------------------------- I.9 Books on Fax ------------------------------------------------------------------------------- "FAX: Digital Facsimile Technology & Applications", 2nd Ed. 338pp. by Kenneth R. McConnell, Dennis Bodson, Richard Schaphorst 1992, Artech House, Norwood, MA. ISBN: 0-89006-495-5 (Order Book No. H04495, $78, Phone: 1 800 225 9977 or 1 617 769-9750) ------------------------------------------------------------------------------- I.10 Other Sources of Information on Fax ------------------------------------------------------------------------------- More detailed information on image file formats and compression may be obtained from the comp.graphics FAQ. The latest version of this FAQ is available on the archive site pit-manager.mit.edu (alias rtfm.mit.edu) as pub/usenet/news.answers/graphics/faq. Information on the Microsoft Windows Telephony API spec may be obtained by ftp ftp.uu.net /vendors/microsoft/tapi-spec or ftp ftp.uu.net /vendors/microsoft/telephony Information on the Internet/fax gateway project may be obtained by sending e-mail to tpc-faq@town.hall.org A mailing list related to the Internet/fax gateway project may be reached through: tpc-rp-request@aarnet.edu.au ZyXEL Modem FAQ Archived at: ftp.cs.psu.edu in /pub/fenner/ZyXEL Digicom FAQ Archived at ftp.rahul.net /pub/wolfgang ZyXEL BBS: (714) 693-0762 Supra BBS: (503) 967-2444 Intel BBS: (503) 645-6275 ------------------------------------------------------------------------------- I.11 Conferences on Fax ------------------------------------------------------------------------------- BIS Strategic Decisions runs several conferences on fax and related technologies. Every spring (May 12-14, 1993) they hold the "Facsimile and Image Communications Conference" and every fall (Nov. 30 - Dec. 1, 1993) they hold the "Annual Computer Fax Conference). For more information call (617) 982-9500 (Fax: 878-6650). ------------------------------------------------------------------------------- I.12 Associations Related to Fax Technology ------------------------------------------------------------------------------- American Facsimile Association Phone: (215) 963-9110 Fax: (215) 451-1156 International Computer Fax Association Phone (617) 982-9500 ------------------------------------------------------------------------------- I.13 Fax-on-Demand Phone Numbers ------------------------------------------------------------------------------- This is a list of collected fax-on-demand numbers for various major computer companies. Please email any additions or corrections to faxfaq@faximum.com Hewlett-Packard 1 800 333 1917 All Products (?) Intel 1 800 525 3019 All Products (?) WordPerfect 1 801 228-9923 WordPerfect Solutions Guide =============================================================================== Subject: P. Product Information =============================================================================== P.1 List of UNIX Fax Software ------------------------------------------------------------------------------- COMMERCIAL ========== -------------------------------------------------- - North America - Alembic Systems International Dfax (800) 452-7608 info@alembic.com Arnet ArnetFAX (615) 834-8000 clarence@arnet.com Black and White Software NXFax (802) 496-8500 (802) 496-5112 nxfax@bandw.com COS Inc. TruFax (609) 771-6705 (609) 530-0898 trufax@cosi.com DigiBoard DigiFAX (612) 943-9020 support@dbsales.digibd.com Faximum Software Faximum ELS, Faximum PLUS (604) 925-3600 (604) 926-8182 info@Faximum.com ICSW 800.486.7274 or 602.998.8623 Intuitive Technology FaxLink (409) 762-8456 Siren Software Siren Fax 1 800 45-SIREN UniSal System FaxTrax (201) 729-9221 V Systems VSI-Fax (714) 545-6442 Brad@VSI.com Company Unknown FaxFX (708) 574-3600 Company Unknown FAXSMART Phone Unknown Company Unknown Fax*Starx (800) 327 9859 - Europe - comFax Com-M-Tex +49 89 546130-0 i link GmbH mix fax +49 30 216 20 48 netCS GmbH netFAX +49 30 787999-0 QUEST systems GmbH FaxX +49 231 914028-0 +49 231 914028-40 faxx@quest.sub.org Signify Software Products i(F)x Faxsoftware for UNIX +31-(0)3480-30131 +31-(0)3480-30182 gerard@integrity.nl smoFax SMO GmbH +49 721 551971 PUBLICALLY AVAILABLE ==================== FlexFAX ======= Overview -------- FlexFAX is a facsimile system for UNIX systems. It supports: o sending facsimile o receiving facsimile o polled retrieval of facsimile Facsimile can be any size (e.g. A4, B4), either 98 or 196 lpi, and transmitted/received as either 1D-encoded or 2D-encoded facsimile data (2D-encoded data is frequently more compact and hence takes a shorter time to communicate). Outgoing documents can be any format; the sendfax program uses a rule-based definition file similar to the System V /etc/magic file to deduce document types and to decide how to convert each document to a form suitable for transmission (either PostScript or TIFF/F). Automatic cover page generation is supported and users can easily tailor cover pages to their environment. A simple text-based phonebook database is supported by sendfax. Information is also provided on how to trivially setup an email to fax gateway service. Incoming facsimile are stored in a receiving area as TIFF/F files and may be automatically delivered by mail and/or printed. A fax server status program, faxstat, can be used to monitor the send and receive queues, as well as the state of facsimile servers. The system supports a wide variety of fax modems. Any Class 1 or Class 2 modem should work with the system. The following modems have been used successfully with the software: Class 1 modems: Digicom Scout+ (firmware revision 2A19/2931 or newer) Nuvo Voyager 96424PFX (firmware revision AF-C2500-E0) SupraFAX v.32bis (firmware revision V1.200-H or newer) NOTE: SEE THE SECTION "Class 1 Modem Support" FOR IMPORTANT INFO ON THE CLASS 1 MODEM SUPPORT Class 2 modems: Boca M1440E (firmware revision V1.270 or newer) Dallas Fax (no longer sold, not recommended) Everex 24/96D (no longer sold) Hayes Optima 24+Fax96 (firmware revision TR00-J260-001 XXX or newer) Multi-Tech 1432BAI (firmware revision 0307 I or newer) SupraFAX v.32bis (firmware revision V1.200-C or newer) Telebit WorldBlazer (firmware revision LA7.01) Twincom 144/DF (firmware revision V1.200 or newer) ZyXel U1496E (firmware revision 5.01 or newer) Other modems: Abaton InterFax 24/96 (no longer sold) Note however that some modems perform better than others. The file MODEMS included in the distribution provides information about each modem that has been tried. Supported Systems ----------------- The software has been ported to the following systems: sgi Silicon Graphics 4D machines w/ AT&T C++ compiler or gcc 2.3.3 sun Sun3/Sun4 w/ SunOS 4.1.X and GNU gcc 2.3.3 bsdi BSD/386 1.0 w/ GNU gcc 2.3.3 386bsd 386bsd 0.1 on an Intel 486 w/ GNU gcc 2.3.3+patches svr4 System V Release 4 on an Intel x86 w/ GNU gcc 2.3.3 (incomplete) solaris2 Solaris 2.x on a Sun4 with GNU gcc 2.3.3 (incomplete) sco SCO ODT 2.0 (incomplete) Systems that are marked (incomplete) compile properly and can be used to send and receive facsimile, but may have known problems or may be lacking some utilities such as the faxaddmodem installation script. Porting the software is usually straightforward provided there is a working C++ compiler (e.g. gcc), PostScript imaging facility (e.g. ghostscript), and support for a limited subset of the POSIX system call interface. System requirements are described more fully in the source code distribution. How to Obtain the Distribution by FTP ------------------------------------- The source code is available for public ftp on sgi.com sgi/fax/v2.1.src.tar.Z (192.48.153.1) You can also obtain inst'able images for Silicon Graphics machines from sgi.com sgi/fax/v2.1.inst.tar (192.48.153.1) For example, % ftp -n sgi.com .... ftp> user anonymous Password: ftp> cd sgi/fax ftp> binary ftp> get v2.1.src.tar.Z .... ftp> quit In general, the latest version of the 2.1 release of the software is always available as "v2.1.src.tar.Z" or "v2.1.inst.tar" in the ftp directory. This file is a link to the appropriate released version (so don't waste your time retrieving the linked file as well!) Any files of the form v2.1.*.patch are shell scripts that can be used to patch older versions of the source code. For example, the file v2.1.0.patch would contain patches to update v2.1.0.tar.Z. Patch files only work to go between consecutive versions, so if you are multiple versions behind the latest release, you will need to apply each patch file between your current version and the latest. GNU NetFax (a.k.a. fax-3.2.1) ============================= on uunet.uu.net as systems/gnu/fax-3.2.1.tar.z (gzip format) To answer all the queries on NetFax: - I have taken over maintenance of NetFax. - I am currently integrating numerous fixes provided by various people which include: - support for Zykel Modems - Use more standard Class 2 commands - Setup configuration files for modems - support for Xenix (This isn't a priority, except that I'm already doing it for a client) - Better compilation and installation - There are a lot of problems with the current release, I don't expect that it will work on the majority of modem/system combinations without work. - If you have any fixes, or improvements please send them to me mintha@geog.ubc.ca or bug-fax@ai.mit.edu - I hope to have a new release out in a few weeks. Following are some hints on getting the current version of NetFax working (for the impatient :) I haven't tried all of these but they may help. - Use GNU make - It won't work on Xenix - If when you send a fax, it gets received twice as long as it should (22 inches instead of 11) try: - Use dfaxlow driver with Ghostscript (easiest) or - Change the source to use the +FDCC=xxxx/+FDCS=xxxx instead of +FDT=xxx The following modems are reported to work with NetFax 3.2.1 Supra FaxModem 14.4 (v. 1.20C or later) Vivi 2496ef FaxModem (Has the resolution problem described above) Everex 24/96 D If you'd like to help me testing the new version, especially if you have something other than Supra Faxmodems, drop me a line. Jim -- Jim Mintha Home: (604) 731-7240 or 737-6094 mintha@geog.ubc.ca Work: (604) 822-2269 or 465-5074 ------------------------------------------------------------------------------- P.2 List of MS-DOS Fax Software ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- P.3 List of MacIntosh Fax Software ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- P.4 List of Windows Fax Software ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- P.5 List of OS/2 Fax Software ------------------------------------------------------------------------------- ------------------------------------------------------------------------------- P.6 List of Fax Modem Vendors ------------------------------------------------------------------------------- Company Classes Phone Fax ===================== ======= ============== ============== -- North America -- AT&T Paradyne 1 (813) 530-2090 (813) 530-2103 Computer Peripherals 2 (805) 499-5751 (805) 498-8306 Hayes 1 (404) 441-1617 (404) 441-1213 Intel 1 (503) 629-7354 (503) 629-7580 MICC 2 (408) 980-9565 (408) 980-9568 Macronix 2 (408) 453-8088 MultiTech Systems 2 (612) 785-3500 (612) 785-9874 Practical Peripherals 1,2 Supra Corporation 1,2 (503) 967-2400 (503) 967-2401 Telebit 2 (408) 734-4333 (408) 734-3333 The Complete PC 1,2 (408) 434-0145 (408) 434-1048 U.S. Robotics 1 (800) DIAL-USR (708) 982-5253 Zoom 2 (617) 423-1072 (617) 423-9231 ZyXEL USA 2 (714) 693-0808 (714) 693-8811 -- Australia (courtesy of adam@saki.com.au )-- Supplier Model Class Phone/Fax ================== ============= ======== ================== NetComm M4F, M7F 2,2.0 +61 2 888 5533 Dataplex DPX-223 2 +61 3 210 3333 DPX-225 2 Interlink Fax Modem 3 2 +61 3 525 3388 Maestro 9600XR 2 +61 6 239 2369 Banksia BitBlitzer 2 +61 2 418 6033 -- Europe -- Dr. Neuhaus ? ? +49 40 55304290/+49 40 55304180 ------------------------------------------------------------------------------- P.7 List of Fax Board Vendors ------------------------------------------------------------------------------- This lists companies that produce intelligent fax boards typically intended for high-volume and multi-line operation. Reliability and functionality rather than price are the consideration here. Company Operating System ====================== ===================== Brooktrout Technology dos,unix,OS/2,others Needham, MA 617-449-4100 Dialogic dos,unix 201-334-8450 Gammalink dos,OS/2 408-744-1400 ------------------------------------------------------------------------------- P.8 List of Vendors of Secure Fax Equipment ------------------------------------------------------------------------------- The only reference so far (courtesy of Jean-Bernard Condat) is to: Mr David COHEN SKTT Henry Kam Technologies & Telecommunations 2d rue de l'Epine Prolongee 93541 Bagnolet Cedex Phone: +33 1 42 87 54 00 Fax: +33 1 42 87 23 91 -------------------------------------------------------------- Contributors to and/or Sources of Information Used in this FAQ -------------------------------------------------------------- adam@shinto.saki.com.au (Adam Donnison) dir@teal.csn.org (Daniel I. Rosenblatt) gerard@integrity.nl (Gerard Huysmans) hrs1@cbnewsi.cb.att.com (herman.r.silbiger) jbcondat@attmail.com (Jean-Bernard Condat) jfreeman@frontporch.win.net (Jeff Freeman) jmccormack@wrglex.uucp (Jim McCormack) johnh@cs.arizona.edu (John M Hughes) jr9283@rapa1.sbc.com (Joe Richmeyer) mckeeveb@monashee.sfu.ca (Rob McKeever) mintha@geog.ubc.ca (Jim Mintha) naddy@mips.ruessel.sub.org (Christian Weisgerber) pso@ibid.gatech.edu (Paul O'Fallon) regebro@stacken.kth.se (Lennart Regebro) root@gandalf.greenie.gold.sub.org (KlausRosenauer) sam@sgi.com (Sam Leffler) tnixon@microsoft.com (Toby Nixon) udo@sensai.quest.sub.org (Udo Klimaschewski) uli@sensai.quest.sub.org (Uli Zug) wes@kofax.com (Wes Chalfant) wrob@unixg.ubc.ca (Robert Wong) and of course, the author/editor of this FAQ: pajari@Faximum.com (George Pajari) -------------------------------------------------------------------------- Copyright 1994 Faximum Software Inc. All Rights Reserved. Permission is granted to copy or distribute this faq (in whole or part) for non-commercial purposes as long as the copyright notice is reproduced and acknowledgement given. Requests for permission for commercial reproduction or distribution (if you are uncertain if it is commercial, ask) should be mailed to the author: pajari@Faximum.com -------------------------------------------------------------------------- -------------------------------------------------------------------------------